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UNIT
ED ST
ATES
DEP
ARTM
ENT
OF T
HE IN
TERI
OR
GEOL
OGIC
AL SURVEY
CHEM
ICAL
METHODS F
OR A
NALY
SIS
OF RO
CKS
AND
MINE
RALS
By
Mar
cely
n J.
C
rem
er,
Pau
l R.
K
lock
, S
arah
T.
Nei
1,
and
John
M.
Riv
ieT
lo
U.S
. G
eolo
gica
l S
urve
y,
Men
lo
Par
k,
Calif
orn
ia
9402
5
U.S
. G
eolo
gica
l S
urve
y O
pe
n-f
ile
Rep
ort
84-5
65
1984
Thi
s re
port
is
pre
limin
ary
an
d ha
s no
t be
en e
dite
d o
r re
view
ed
for
con
form
ity w
ith
Geo
logi
cal
Sur
vey
stan
dard
s an
d no
men
clat
ure.
Chemical lite
ratu
re c
ontains
an a
bund
ance
of
anal
ytic
al pr
oced
ures
su
itab
le f
or r
ock
and
mine
ral
anal
ysis
. Each o
f the
auth
ors
of t
his
manu
al ha
s traine
d other
chemical analysts i
n th
e la
bora
tory
. They
realized t
he n
eed
for
a co
ncis
e wr
itte
n guide
for
the
trainee.
"Che
mica
l Me
thod
s fo
r An
alys
is o
f Rocks
and
Minerals"
was
thus
conc
eive
d an
d as
sembled, intended a
s a working
guid
e for
the
chemical
anal
yst.
Th
e me
thod
s de
scri
bed
were
der
ived
from
many
sou
rces a
nd m
ay
incl
ude
minor mo
difi
cati
ons
or a
dapt
atio
ns f
or s
pecific
situations o
r available
equi
pment.
The
user
is
refe
rred
to
publ
ishe
d wo
rks
for
the
unde
rlyi
ng c
hemi
cal
theo
ry.
The
writers
are
inde
bted
to
C. Ti
lbur
y,
D. Vi
vit,
an
d D.
Sh
epar
d fo
r th
eir
advi
ce a
nd a
ssis
tanc
e in
the
completion o
f th
is g
uide.
CONT
ENTS
I.
Pre
para
tion:
Gla
ssw
are
, cle
anin
g
1 P
lastic,
cho
ice
an
d ca
re o
f
2 P
latin
um
, ca
re
and
use
of
3m
i y
inn
_
__
__
_ _
___ _
__
_ . _
_
_ . _
. _ _
_ ._
._ _
_ _
__
-,.
fiII
I I
/\ |
| | y
__
__
_____*._
*._
*.
u
II.
Met
hods
o
f A
na
lysi
s:1.
C
ol o
r im
e tr
ie:
Al u
mi n
urn
7p|
r» 1
np
"i n
p_
_
«
_ ._
_
__
__
__
__
__
__
-.
-._
_____ _
-._
_ .
1 1
V^
l I
I V
/l
I I
IV-
«
«
^ ̂
Chr
omiu
m
25T
rnn
tn
tal
_
_ _
_
_
__
__
__
_
1 "^
Zl
wl
I ,
l*W
i*
Q | -» -. ._
_
_
____
A
O
Phos
pho
r us
16O
I I
I
L« U
i | - - . . . .
XO
Ti ta
n i u
rn
20
2.
Gra
vim
etr
ic:
Axin
ite
, a
boro
n
min
era
l
23
Chr
ome
spin
el,
an
oxi
de
25
Ph
osp
ha
tes:
Pho
s ph
or u
s
30
Mai
n p
ort
ion
36
Am
mon
ia
pre
cip
itate
-
44
Silic
ate
s:
Mai
n P
ort
ion:
Fusi
on
and
wate
r m
inus
49S
i 1 i c
a
54In
terf
ere
nce
s
74R
ecov
ery
fro
m
amm
onia
gr
oup
61A
mm
onia
gr
oup
57P
latin
um
rem
oval
61M
anga
nese
63R
ecov
ery
fro
m
calc
ium
67R
ecov
ery
fro
m m
agne
sium
72C
al c
ium
65R
ecov
ery
fro
m m
agne
sium
70M
agne
s iu
m
68In
com
ple
te
sam
ple
att
ack
78S
ul fur
, to
tal
79Su
1 f u
r tr
i o
xi d
e
84W
ate
r,
Pe
nfie
ld
Met
hod
87
CONT
ENTS
(c
ontin
ued)
3.
Mis
cella
ne
ou
s:A
cid
de
com
po
sitio
n,
HN
03,
HC
104
, H
F --
90
Bor
on,
ion
exchange
92
Car
bon: A
cid
solu
ble
, co
ulo
me
tric
96
T
ota
l, com
bustion
102
Den
s i t
y, p
ow
de
r
108
Flu
orine:
In silic
ate
s:
Na2
C03
sin
ter
111
Li B
02
fus io
n -
114
In phosphates
119
Iron,
ferr
ous, titratio
n
121
Man
gane
se, titra
tio
n
127
Me
rcu
ry,
cold
va
po
r
131
Mol
ybde
num
, e
xtra
ctio
n
137
Pot
assi
um
and
sodi
um,
flam
e p
ho
tom
etr
ic
13
9W
ater
, m
icrocoulo
metr
ic
144
CLEA
NING
LABORATORY
GLAS
SWAR
E
It is important
that al
l glassware
be scrupulously c
lean an
d the
insi
de walls
be e
ntir
ely
free o
f grease.
No exact
meas
urem
ents
of v
olume
can
be m
ade
if t
he w
alls of
the
glassware
are
grea
sy e
ven
to the
slightest
exte
nt.
1. Rinse
glas
swar
e with water
several
time
s to
rem
ove
the
contained
solution.
2. Scrub
with a
soap
sol
utio
n if
pa
rtic
les
are
clin
ging
to
the
glas
swar
e.
3. Immerse
in a 82504-003
acid
mix
ture
(2
0.4
g O03/1000 m
l H2
S04;
well leached).
4. Rinse
glassware
exte
nsiv
ely
with h^O
at least
7 ti
mes
and
run
plenty o
f H^O
to avoid
the
subsequent formation
of
toxic
5. Immerse
glas
swar
e in a
HC1-
H202
ac
id r
inse
(dilute
HC1
with a
few
ml
6. Rinse
with h^O
again
seve
ral
times.
7. Finally
rinse
several
time
s with distil led-deionized 1^0.
8. Ai
r dry
over W
hatman No
. 1
filt
er pa
per.
9. For
glassware
to be
used in de
term
inin
g ch
lori
ne,
HN03 c
an be
exchanged fo
r HC
1 in the
rinse
solution.
Comp
iled
by
P. Klock
CH
OIC
E AN
D CA
RE
OF
PLA
STI
C
CO
NTA
INER
S FO
R ST
ORA
GE
OF
TRAC
E EL
EMEN
T SA
MPL
ES
(Fro
m
Se
lect
ion
an
d cl
ea
nin
g o
f p
lastic
conta
iners
fo
r st
ora
ge o
f tr
ace
el
emen
t sa
mpl
es
by
John
R.
M
oody
an
d R
ich
ard
M
. L
ind
stro
m,
Anal.
Che
m.,
v.
49,
no.
14,
Dec
. 19
77,
p.
2264
-226
7)
Tw
elve
diffe
rent
pla
stics
wer
e ex
amin
ed b
y g
ravi
me
try,
is
oto
pe
dilu
tion
mas
s sp
ect
rom
etr
y,
and
neutr
on
activation
analy
sis
. T
eflo
n
and
conve
ntio
nal
poly
eth
ylene
(CPE
) bottle
s
wer
e th
e le
ast
conta
min
atin
g o
nce
they
wer
e cl
ea
ne
d.
The
study
incl
uded
LPE
, PP
, PM
P,
PC,
PVC
, C
PE,
TFE
, an
d FE
P bottle
s.
Spe
cim
ens
of
Te
fze
l o
r E
TFE
, T
eflo
n
PFA,
PS
, an
d TP
T w
ere
als
o
exam
ined
. Th
e fo
llow
ing
ste
ps
are
reco
mm
ende
d fo
r cl
eanin
g pla
stic
con
tain
ers
:
1.
Fill
with
1+1
HC1
(AR
gra
de).
2.
Allo
w
to
sta
nd
one
wee
k a
t ro
om
tem
pe
ratu
re
(80°
C fo
r te
flon).
3.
Em
pty
and
rin
se
, w
ith dis
tilled
1^0.
4.
Fill
with
1+
1 HN
03
(AR
g
rad
e).
5.
Allo
w
to
sta
nd
on
e w
eek
at
room
te
mpera
ture
(8
0°C
fo
r te
flo
n).
6.
Em
pty
and
rin
se
with
d
istille
d
HzO
.
7.
Fill
with
p
ure
st
ava
ilable
dis
tilled w
ate
r.
8.
Allo
w
to
stand
seve
ral
wee
ks
or
until
need
ed,
cha
ng
ing
wat
er
periodic
ally
to
in
sure
co
ntin
ued
cleanin
g.
9.
Rin
se w
ith
pure
st w
ater
an
d allo
w
to
dry
in
a
part
icle
an
d fu
me-f
ree
en
viro
nm
en
t.
Com
pile
d by
M
. C
rem
er
CARE
AN
D US
E OF
PL
ATIN
UM
WAR
E (c
onde
nsed
fr
om
"Not
es
on
the C
are
and
Use
o
f P
t Labora
tory
W
are
"i)
Pla
tinu
m
is
a re
lative
ly so
ft
met
al
and
regula
r cl
ea
nin
g,
bu
rnis
hin
g,
and
resh
ap
ing
of
the
obje
ct w
ill
pro
lon
g
the
life
of
the
ware
. A
ccura
te re
su
lts
from
its
use
are
o
bta
ine
d.
For
a m
ore
deta
iled
acco
unt
of
the su
bje
ct,
se
e re
f.
1,
2,
and
3.
Pla
tinum
Car
e:
1.
Aft
er
any
type of
fusi
on
in
p
latin
um
, so
ak
in
1 +
1 HC
1 on
a
stea
m bath
.
2.
Rin
se
tho
rou
gh
ly w
ith d
istille
d
h^O
an
d ru
b g
en
tly w
ith
roun
ded
gra
ins
of
moi
sten
ed
sand
w
hich
w
as
pre
vio
usly
se
lect
ed
and
ca
refu
lly
clea
ned
for
use
on
pla
tinum
.
3.
Pla
ce
pla
tinu
m
in
the
pro
pe
r re
sha
pin
g b
lock
; b
urn
ish
or
stro
ke w
ith
the
pla
tinu
m
gra
in
usi
ng
a
bu
rnis
hin
g to
ol
pe
rio
dic
ally
cl
eane
d w
ith
a so
ft
croc
us
clo
th.
4.
Fin
ish
by
imm
ersi
ng
the
pla
tinum
in
ch
rom
ic
aci
d
cleanin
g so
lutio
n
(H2S
04~C
r03)
;
rinse
thoro
ughly
with
dis
tilled
5.
Fin
ally
, ig
nite
the w
are
at
1000
°C fo
r 1/2
h
ou
r;
store
in
a
desi
ccato
r to
cool.
Insp
ect
th
e
pla
tinum
fo
r an
y d
isco
lora
tio
n.
If
the
pla
tinum
is
b
rig
ht
and
shin
y, it
is
read
y fo
r re
use
. If
n
ot,
co
ntin
ue
with
st
ep 6
.
6.
In
the
dis
colo
red
pla
tinu
m v
ess
el,
melt
pota
ssiu
m
pyr
'osu
lfate
ov
er
a lo
w
flam
e
from
a
Tirrill
bu
rne
r.
The
white
$0
3 fu
mes
, th
e
cle
an
sin
g a
ge
nt,
sh
ould
es
cape
o
nly
slo
wly
. P
lace
ve
ssel
on
a
porc
ela
in
pla
te
to
coo
l. G
en
tly
knoc
k out
the
hard
ened
melt;
pla
ce
the
pla
tinum
in
boili
ng ^0 u
ntil
the
ba
lanc
e of
the
melt
dis
solv
es.
7.
Aga
in
clean
the
pla
tinum
in
ch
rom
e-s
ulfu
ric
acid
, rin
se
an
d re
ignite,
cool,
and
agai
n ch
eck
for
dis
co
lora
tio
n.
Ste
ps
6 an
d 7
mus
t be
re
pe
ate
d u
ntil
the
pla
tinum
is
no
lo
ng
er
dark
.
If
pla
tinu
m w
as
used
only
to
drive o
ff
surf
ace
m
ois
ture
in
sa
mpl
es
(105
*
5°C
),
a th
orou
gh
bru
shin
g
and
cleanin
g
in
1 +
1 HC
1 w
ill
su
ffic
e.
Dry
ing
th
e
clea
n pla
tinum
a
t 10
5°
is
adeq
uate
in
th
is
case
. A
t e
leva
ted
te
mp
era
ture
s,
pla
tinu
m slo
wly
vo
latize
s.
Pla
tinum
U
se:
Pla
tinu
m
is
att
ack
ed
un
der
the fo
llow
ing
co
nd
itio
ns:
By h
ea
ting
in
th
e fo
llow
ing
liq
uid
s:
1.
Aqu
a R
egia
.
2.
Hyd
roch
loric
aci
d
and
oxid
izin
g
ag
en
ts.
3.
Co
nce
ntr
ate
d sulfuric
acid
. Th
e a
ctio
n
is
ext
rem
ely
sl
ow
and,
fo
r all
lab
ora
tory
purp
ose
s,
neglig
ible
.
4.
Co
nce
ntr
ate
d
ph
osp
ho
ric
aci
d.
Her
e ag
ain
the
act
ion
is
notic
eable
o
nly
a
fte
r ve
ry
pro
lon
ge
d heatin
g.
;
By h
eati
ng in
the
following
soli
ds,
their
fusi
ons
or vapors:
1. Su
lfur
, selenium,
and
tellurium.
The
acti
on o
f su
lfur
vapor is
ver
y slow,
and
prolonged
heat
ing
is required
to produce
any
serious
effe
ct;
selenium a
nd t
ellu
rium
rea
dily
com
bine w
ith
platinum.
2. Phosphorus,
arsenic, an
d antimony.
Comb
inat
ion
with pl
atin
um o
ccurs
read
ily.
3. Magnesium
pyrophosphate
above
900°C.
4. Si
lica
an
d borax
at h
igh
temp
erat
ures
.
5. Mo
lten
lead,
zinc,
tin, bi
smut
h, silver,
gold
, or
co
pper
or mi
xtur
es which
form
the
se m
etal
s by
red
ucti
on.
6. Fused
alka
li oxides an
d peroxides, and, to a
smaller
exte
nt in the
presence o
f ai
r, al
kali
hy
drox
ides
.
7. Fused
nitrates.
The
acti
on is
in
tens
ifie
d by
the presence of
al
kali
hy
drox
ides
or
ca
rbon
ates
, bu
t in no
ca
se
is it
ver
y se
vere
.
8. Phosphorus pentoxide
or ph
osph
oric
acid.
The
action is
re
lati
vely
li
ttle
.
9. Fu
sed
cyanides.
Plat
inoc
yani
des
are
formed.
10.
Iron
oxide
above
1200
°C.
Oxyg
en is
liberated
and
the
iron
combines wi
th th
e platinum.
11.
Silica,
silicates, alumina, an
d ma
gnes
ia above
1600
°C.
At lower
temperatures,
no action oc
curs
.
12.
Fused
alka
li an
d alkali chlorides
in th
e presence of
ai
r at
10
00°C
or above.
13.
Lead an
d bi
smut
h ox
ides
above
1250°C.
Compiled b
y P.
Kl
ock
REF
EREN
CES
1.
J.
Bis
hop
a C
ompa
ny,
Not
es
on
the
care
an
d us
e of
pla
tinu
m
labora
tory
war
e.
2.
Kolthoff,
I.
M.,
and
Sa
nd
ell,
E.
B
.,
1952
, T
extb
ook
of
quantita
tive
inorg
anic
analy
sis
, 3rd
ed.:
New
Yo
rk,
Mac
mill
an
Com
pany
, 75
9 p.
3.
Kolthoff,
I.
M.,
Sandell,
E.
B
.,
Mee
han,
E.
J.,
an
d B
ruck
enst
ein
, S
tanle
y,
1969
, Q
ua
ntita
tive
C
hem
ical
A
naly
sis,
4
th
ed.,
Lond
on,
Ma
cmill
an
Com
pany
, C
olli
er-
Macm
illan.
SAM
PLE
HA
ND
LIN
G-M
IXIN
G
All
the
ca
refu
l w
ork
put
into
a
good
a
na
lysi
s (g
ravim
etr
ic
or
inst
rum
en
tal) w
ill
be
for
naug
ht if
the
sam
ple
take
n is
not
repre
senta
tive o
f th
e o
rig
ina
l m
ate
ria
l.
La
bo
rato
ry
sam
ples
o
f ro
cks
and
min
era
ls
req
uire
fr
eq
ue
nt
mix
ing,
to
min
imiz
e
seg
reg
atio
n o
f m
inera
ls
by g
ravity
due
to
ever
yday
p
ack
ing
, us
age,
an
d handlin
g.
Bef
ore
any
analy
sis
, an
d eve
ry
two
wee
ks
there
after
during a
na
lysis
, ea
ch
sam
ple
is
mix
ed
usi
ng
a te
chniq
ue
term
ed
"co
nin
g
and
quart
ering"i
.
Pro
cedu
re
1.
Co
mp
lete
ly
empt
y sa
mpl
e b
ott
le
on
an
8"
x 12
" sh
eet
of
Alb
anen
e pa
per
(100
p
erc
en
t ra
g).
2.
Roll
pow
der
over
itself
100
times,
by
ra
isin
g t
he
co
rners
of
the
pape
r in
su
cce
ssio
n.
3.
Usi
ng
a sp
atu
la,
split
the
sam
ple
into
quart
ers
.
4.
Ca
refu
lly tr
ansfe
r on
e se
t of
opposi
te
sides
back
in
to origin
al
conta
iner
(do
no
t p
ack
).
5.
Com
bine
th
e oth
er
set
of
op
po
site
si
des
and
repeat
steps
2-5
.
6.
Rep
eat
the
proc
edur
e u
ntil
sam
ple
con
tain
er
is fu
ll
(dis
card
ex
cess
sa
mp
le).
Com
pile
d by
P.
K
lock
REFE
RENC
E
1.
Ko
lth
off
, I.
M
., an
d S
andell,
E.
B
.,
1952
, T
extb
ook
of
quantita
tive
ino
rga
nic
a
na
lysis
, 3
rd ed.:
New
York
, M
acm
illan
C
ompa
ny,
759
p.
COLO
R IM
ETR
1C
(Ada
pted
fr
om
The
Direct
M
icro
de
term
ina
tion
o
f S
ilicon
and
Alu
min
um
in
Sili
ca
te
Min
era
ls;
U.S
. G
eo
log
ica
l S
urve
y P
rofe
ssio
nal
Pap
er
650-
B,
p.
B13
6-B
139,
R
ober
t M
eyr
ow
itz).
Alu
min
a (A
1203
) is
de
term
ined
spectr
ophoto
metr
ically
by
mea
surin
g th
e
abso
rptio
n
of
lig
ht
at
475
nm b
y a
calc
ium
al
umin
um A
lizarin
Red
-S
com
plex
. Th
e sa
mpl
e is
fu
sed
with
Li
B02
, d
isso
lve
d
in
4 perc
ent
HN
03,
and
mad
e to
vo
lum
e.
The
colo
red
co
mpl
ex
is
deve
lope
d by
ta
kin
g
an
appro
priate
a
liqu
ot
to
whi
ch
is
adde
d C
aCl2
> N
H20
H.H
C1,
K
3Fe(
CN
)6,
merc
apto
ace
tic
aci
d
(a.k
.a.
thio
gly
colic
acid
),
bu
ffe
r,
and
Aliz
arin
R
ed-S
. Th
e us
ual
conce
ntr
atio
n
of
flu
orin
e
foun
d do
es
not
inte
rfere
, b
ut
appre
ciable
q
ua
ntitie
s of
iro
n
and
tita
niu
m
als
o
form
co
lore
d
com
plex
es
tha
t ab
sorb
at
475
nm.
Iro
n
can
be
tole
rate
d
in
a ra
tio
to
A
1203
o
f tw
o to
on
e.
Tita
niu
m
inte
rfere
nce
is
no
t e
limin
ate
d
bu
t is
co
rre
cte
d
from
an
em
piric
ally
d
erive
d
table
.
Rea
gent
s (a
ll ch
em
icals
-reagent
gra
de):
Cal
cium
ch
lorid
e
solu
tion:
Tra
nsf
er
7 g
of
CaC
03
to
a 25
0 m
l beake
r.
Add
50 m
l o
f h^
O
and
then
ad
d d
ilute
HC1
drop
wis
e w
ith
const
ant
stirr
ing u
ntil
all
CaC
03
is
dis
solv
ed
. B
oil
the so
lutio
n
for
1 or
2
min
utes
to
rem
ove
the
dis
solv
ed
C02
- C
oo
l. F
ilte
r th
rough
a fa
st
pape
r;
dilu
te
to
500
ml
and
mix
we
ll.
Hyd
roxy
lam
ine
hyd
roch
loride solu
tion,
10
perc
ent
(w/v
):
Pre
pare
an
d filter.
Pot
assi
um fe
rric
yanid
e so
lutio
n,
0.75
p
erc
en
t:
Pre
pare
fr
esh
ea
ch
day.
Merc
apto
ace
tic
aci
d
so
lutio
n
(a.k
.a.
thio
gly
colic
acid
),
1.6
perc
ent
(v/v
):
Pre
pare
fr
esh
ea
ch
day.
Bu
ffe
r solu
tion:
Pre
pare
50
0 m
l so
lutio
n
to
con
tain
10
0 g
sodi
um
ace
tate
, ^2^2- 3
^0
. F
ilte
r th
roug
h a
fast
filter
pape
r.
Aliz
arin
Red
-S
(aliz
arin
sodi
um m
onosu
lfonate
) so
lutio
n,
0.05
p
erc
en
t (w
/v):
P
repa
re
500
ml;
filter
thro
ug
h
a sl
ow
paper. P
roce
dure
C
omm
ents
1.
Thoro
ughly
mix
an
d quart
er
sam
ples
, NB
S 99
a or
1.
Th
e 19
p
erc
en
t lim
itation
insu
res
a fin
al
A^0
3e
qu
iva
len
t,
and
one
or
two
oth
er
sta
nd
ard
ro
ck
pow
ders
co
nce
ntr
atio
n
no
t to
ex
ceed
0.
95
ppm
, th
e
uppe
r lim
it
who
se
A12
03
valu
e
does
not
exce
ed
19
perc
ent.
for
this
pro
cedure
. If
Si
02
was
d
ete
rmin
ed
, st
eps
1-5
are
om
itte
d.
An
aliq
uot
of
the
solu
tion
deve
lope
d fo
r S
i02
is
used
in
st
ep 6
.
2.
Into
a
glaz
ed
bla
ck
po
rce
lain
cru
cib
le
wei
gh
40 m
g o
f 2.
No
m
ore
than
41.5
m
g o
f NB
S 99
a sh
ou
ld
be w
eigh
ed
or
sam
ple.
Ad
d to
th
e
cru
cib
le
350
mg
LiB
02-
Mix
th
e
0.95
pp
m lim
it w
ill
be
exce
eded
. NB
S 99
a is
a
thoro
ughly
with
a
pla
tinum
ro
d
or
sta
inle
ss
ste
el
soda
fe
ldsp
ar
with
in
sig
nific
an
t am
ount
s o
f tita
niu
m
sp
atu
la,
and
tra
nsfe
r th
e m
ixtu
re
to
a gra
phite
an
d iro
n.
cru
cib
le
as
de
scrib
ed
in
Na
an
d K
pro
ced
ure
.
3.
In
the
sa
me
man
ner,
pre
pare
40
mg,
30
mg,
an
d 20
mg
mix
ture
s of
NBS
99a
to
be
used
as
a
calib
ration
curv
e.
Als
o
pre
pa
re 4
0 m
g m
ixtu
res
of
the o
the
r st
andard
rock
po
wde
rs
to b
e us
ed
to
test
the
pro
cedure
.
4.
Pre
pare
a
bla
nk
by w
eig
hin
g 3
50 m
g of
LiB
02
and
transfe
rrin
g it
to
a g
rap
hite
cru
cib
le.
5.
Pro
ceed
w
ith
Ste
ps
4 th
roug
h 6
of
"Pro
cedure
fo
r C
olo
rim
etr
ic
De
term
ina
tion
of
Si0
2".
6.
To
deve
lop
the
com
plex
, tr
ansfe
r 3
ml
aliq
uo
ts o
f ea
ch
6.
Thr
ee m
illilite
rs
of
the o
rig
ina
l solu
tion re
su
lts
in
so
lutio
n
to
a se
ries
of
100
ml
volu
me
tric
flasks.
no so
lutio
n
gre
ate
r th
an
~0.
91
ppm
in
A
1203
or
( 40
mg)
(1
000
pcj)
(0.1
906)
(3
ml
) *
0.91
p£
(250
ml
) __
__
mg _
__________
ml
100
mg
beca
use
[A1
203]
in
NB
S 99
a =
19.0
6 p
erc
en
t.
7. To ea
ch solution,
add
2.0
ml CaCl2
solution,
1.0
ml
hydroxylamine
hydr
ochl
orid
e, 1.
0 ml
po
tass
ium
ferr
icya
nide
, and
2.0
ml of m
erca
ptoa
ceti
c ac
id.
Allo
w to s
tand for
5 mi
nute
s.
8. Add
10.0 m
l bu
ffer
so
luti
on,
minutes.
Allo
w to stand
for
10
9. Add
10.0 m
l of
Alizarin
Red-S
solu
tion
with a
volumetric pi
pet.
Dilute to m
ark, mi
x, an
d le
t stand
fo
r 45
to 75 m
inutes.
Measure
abso
rban
ce at 47
5 nm
.
An e
asier
and
permissible
meth
od is to
mix
together
suff
icie
nt po
rtio
ns of
2.0
ml
CaCl2
solu
tion
, 1.0
ml
hydr
oxyl
amin
e hydrochloride, an
d 1.
0 ml
po
tass
ium
ferricyanide.
Then ad
d to ea
ch so
luti
on 4
ml of the
mixt
ure
and
2.0
ml me
rcap
toac
etic
acid.
Potassium
ferr
icya
nide
and
mercaptoacetic acid serve
as
complexing agents for
iron.
Some sample so
luti
ons
turn
green
with th
e addition of
K3Fe(CN)5;
some
solu
tion
s become co
lorl
ess
with th
e ad
diti
on of
me
rcap
toac
etic
ac
id;
any
color
remaining
in any
sample
solu
tion
vanishes with th
e addition of the
buff
er.
9. Th
e co
mple
x is
formulated as
fo
llow
so
s/c\/\/S(
V
10.
Treat
the
NBS
stan
dard
feldspar
data b
y th
e le
ast
squares
meth
od.
11.
Calc
ulat
e the
appa
rent
^303
content
of the
11.
The
percent
Ti02 is known
in t
he r
ock
standards.
unknowns and
the
rock standards.
Check
the
accu
racy
However, before the
corr
ecti
on to
the
unknowns can
be
of [
A^OS
! in
the r
ock
standards
against
the
made
, pe
rcen
t Ti02 is de
term
ined
as set
forth
in the
"tru
e" values
by
correcting
the
apparent [^203],
proc
edur
e for
colorimetric
calculated fr
om t
he e
quat
ion,
fo
r Ti02
interference.
Use
the
table
given
below.
Corr
ect
the
in the
unknowns in
the sa
me m
anne
r.
Appa
rent
Per
cent
Correction P
erce
ntTi
02
0 0.25
5 0.
2010
0.15
15
0.10
20
0.05
(Apparent
percent
A1203) minus
[(Correction per
perc
ent
Ti02
) (percent T
i02)
]=Pe
rcen
t A1203.
Compiled by M
. Cremer
10
CH
LOR
INE
(Ada
pted
fr
om
New
Co
lorim
etr
ic
De
term
ina
tion
o
f C
hlo
rid
e
usin
g M
erc
uric
Thio
cyanate
an
d F
err
ic
Ion
, by
Iw
asa
ki,
I.,
Uts
umi,
S.,
and
Oza
wa,
T
.,
Bu
lletin
o
f th
e C
hem
ical
S
oci
ety
of
Japa
n,
v.
25,
p.
226,
19
52)
An
aliq
uot
of
the so
lutio
n
from
th
e
leac
hed
sin
ter
prep
ared
fo
r th
e fluoride
de
term
ina
tion
(d
ige
stio
n
met
hod)
is
us
ed
to
deve
lop
the o
rang
e co
lor
of
ferr
ic
thio
cyanate
. F
err
ic nitra
te
and
merc
uric
thio
cya
na
te
are
ad
ded;
th
e so
lutio
n
is
mad
e to
vo
lum
e,
and
abso
rban
ce
is
read
a
t 46
5 nm
. Th
e m
etho
d is
ra
pid
an
d si
mple
fo
r lo
w
conce
ntr
atio
ns
of
chlo
ride.
Rea
gent
s (a
ll
chem
icals
-reagent
gra
de):
Ferr
ic N
itra
te.
Dis
solv
e
70
gram
s o
f F
e(N
03)-
9 H2
0 in
w
ater
co
nta
inin
g
30 m
l o
f co
nce
ntr
ate
d nitric
aci
d
and
dilu
te
to
one
lite
r w
ith
wate
r.
Filte
r th
rough
Wha
tman
no
. 42
paper.
Me
rcu
ric
thio
cya
na
te.
Dis
solv
e
0.3
g
of
merc
uric
thio
cyanate
in
10
0 cc
a
bso
lute
e
thyl
alc
ohol.
Sod
ium
Ch
lorid
e
Sta
ndar
d.
Dis
solv
e
in
H20
1.64
8 g
dry
N
aCl
(2
hour
s at
105°
C
).
Mak
e to
on
e lite
r vo
lum
e.
Pro
cedu
re
Com
men
ts
1.
To
a 10
ml
rock
or
m
inera
l solu
tion
in
a 50
ml
volu
metr
ic flask,
add
5.0
ml
of
ferr
ic nitra
te
solu
tion.
1.
The
reac
tion
s ar
e as fo
llow
s:
2 Cl-
+ Hg(CNS)2
v *
HgCl
2 +
4 Cl-
+ Hg(CNS)2^
^ Hg
Cl/f
"
CNS-
+ F
e+++
; N
Fe(CNS)"
2 CN
S
2.
Add
1 m
l o
f m
erc
uric
thio
cyanate
in
a
bso
lute
alc
ohol.
Dilu
te
to
mar
k an
d m
ix.
3.
At
the
sa
me
time
, pre
pare
a
series
of
NaC
l st
an
da
rds
in
the
sam
e m
anne
r.3.
Th
e m
inim
um
de
term
ina
ble
co
nce
ntr
atio
n
is
0.05
pp
m.
How
ever
, best
re
sults
are
ob
tain
ed
in
th
e ra
nge
0.1
- 20
pp
m C
r.
11
4.
Afte
r 10 m
inut
es,
meas
ure
abso
rban
ce at 4
65 nm
. Pr
epar
e a
calibration
curve
by t
he method o
f le
ast
squa
res.
Re
port
pe
rcen
t Cl
~ in the
unknowns to
on
ly o
ne decimal
place.
4.
The
colo
r is
stable fo
r several
hour
s.
Brom
ide,
io
dide
, cy
anid
e, thiosulfate
and
nitr
ate
interfere.
The
curve
is not
exactly
line
ar.
The
determination
is regarded as
somewhat q
ualitative.
Compiled b
y M. Cr
emer
12
COLO
RIME
TRIC
DE
TERM
INAT
ION
OF T
OTAL IR
ON
Total
iron
as Fe
203
is determined b
y forming
an orange-colored Fe(II)-orthophenanthroline co
mple
x in w
eakl
y ac
id,
neut
ral
or we
akly
alkaline solutions
(pH2-9).
Beer
's la
w is cl
osel
y fo
llow
ed.
The
color
is st
able
fo
r ma
ny m
onth
s.
The
iron in th
e sa
mple
is reduced
with
hydroxylamine
hydr
ochl
orid
e.
Orthophenanthroline
is added, and
the
solution
is bu
ffer
ed w
ith
sodium c
itra
te.
Given
the
same
ori
gina
l so
luti
on described
belo
w, the
reco
mmen
ded
aliquot
will
accommodate
as mu
ch as
15
pe
rcen
t
Reag
ents
(a
ll chem
ical
s-re
agen
t gr
ade)
:
Hydroxylamine
hydrochloride
(10
percent):
diss
olve
50
g Nl
^OH.
HCl
in water
and
dilute to
500 m
l.
Filt
er.
Orthophenanthroline
solu
tion
(0.1 pe
rcen
t):
dissolve 0
.5 g o-
phen
anth
roli
ne m
onoh
ydra
te in w
ater and
dilute to
500
ml.
Filt
er.
Keep s
olution
out
of s
unlight.
Discard
if c
olor de
velo
ps.
Sodi
um c
itrate solution (10
perc
ent)
: dissolve 5
0 g
Filter.
in w
ater
an
d dilute to
500
ml.
Stan
dard
ir
on so
luti
on:
Diss
olve
1.0
00 g
of
iron
met
al st
rip
or w
ire
(99.
9 pe
rcen
t pu
re)
in 20 m
l of
1:1
HC1
and
dilu
te to
on
e li
ter
to pr
ovid
e 1000 ug/ml
Fe.
Procedure
1.
To a
series of
50 m
l vo
lume
tric
flasks,
add
15 m
l ea
ch
of solutions
cont
aini
ng bl
ank,
rock standards, an
d samples.
Comments
1.
The
sample solutions
to b
e us
ed are
those
prep
ared
for
the
colo
rime
tric
de
term
inat
ion
of S
iO^;
i.
e. 40 m
g sample,
350
mg L
iB02 >
250
ml of
4 percent
HNO^
. However, th
e pr
oced
ure
may
also
be
used o
n fu
sion
s ot
100
mg s
amples diluted
to 100
ml (s
ee Na
and
K pr
oced
ure)
. In that event, a
smal
ler
aliquot
is us
ed;
i.e.
10
ml
> 50 m
l.
2.
Prepar
e a
seri
es of s
tandard
iron
so
luti
ons
using
the
1000 p
pm ir
on standard f
or atomic absorption.
To
each
, add
HN03 an
d L1B02
to m
atch
the
sample
solu
tion
s.
3.
To ea
ch,
add
5 ml of h
ydroxylamine hydrochloride.
Swirl
to m
ix an
d allow
to stand
for
one
hour
. >
4.
Pipet
10 m
l of 0.1
percent
o-ph
enan
thro
line
so
luti
on
to e
ach
flas
k and
swirl
to m
ix.
3. 4.
An hour w
ait
is re
comm
ende
d by C
. 0. In
game
lls
who
stat
es that ir
on must be
completely
redu
ced
before
citr
ate
is added.
This
re
agen
t forms
a reddish-orange c
omplex,
C12H8N2J3
Fe^t,
with Fe
lllL
in acidic,
neut
ral
or b
asic
so
luti
on tpH2-9).
foll
owed
cl
osel
y.
, Be
er's
law
is
13
5. 6. 7. 8.
Pi pet
10 m
l of
10
percent so
dium
cit
rate to e
ach
flas
k an
d swirl
to m
ix.
Dilute to volume,
mix
thor
ough
ly,
and
allow
to stand
for
one
hour,
or overnight
if m
ore
conv
enie
nt.
Meas
ure
the
abso
rban
ce o
f the
complex
at 510
nm u
sing
to se
t zero absorbance.
Prepar
e a
line
ar eq
uati
on b
y least
squa
res
using
the
data f
rom
the
standard solutions.
Comp
ute
perc
ent
Fe203
in the
rock standards
and
the
unkn
owns
. Check
perc
ent
Fe203
in th
e rock st
anda
rds
against
the
"tru
e" va
lues
.
Buff
er.
Since
the
complex
1s extremely
stab
le,
the
solu
tion
s show n
o change in color
even af
ter
many
months.
Comp
iled
by M
. Cremer 14
REFERENCES
Bandemer,
S. L.,
and
Schaible,
P. J.
, 19
44,
Dete
rmin
atio
n of ir
on:
Ind.
an
d Eng. Ch
emis
try,
An
al,
ed.,
v. 16,
p. 317-319.
Ingamells, C.
0.
, 1966,
Abso
rpti
omet
ric
Meth
ods
in Rapid
Silicate Analysis:
Anal
ytic
al Ch
emis
try,
v.
38,
p. 1228-1234.
Maxw
ell,
John A.
, 19
68,
Rock
an
d Mineral
Analysis,
New
York
, Interscience Publishers,
p. 211-213, p. 424-425.
Sandell, E. B.,
1959
, Co
lori
metr
ic Determination
of T
race
s of
Metals:
3rd
ed., New
York
In
ters
cien
ce P
ubli
sher
s,
Inc.,
p. 53
7-542.
Shapiro, Le
onard, Rapid
Analysis of Silicate,
Carb
onat
e, and
Phosphate
Rocks Revised
edit
ion:
U.
S. Ge
ol.
Survey
Bull
. 1401,
p. 47-48.
15
COLORIMETRIC DETERMINATION
OF PHOSPHORUS
(Ada
pted
fr
om C
olo
r im
etr
ic
De
term
ina
tion
o
f P
hosp
horu
s as
M
ol y
d iv
ana
do
ph
osp
ho
ric
Aci
d,
R.
E.
Kits
on
and
M.
G.
Me
llon
, In
dustr
ial
and
En
gin
ee
rin
g
Chem
istr
y,
v.
16,
no.
6,
19
44
.)
Sam
ples
ar
e fu
sed
with
lit
hiu
m
met
abor
ate
and
dis
solv
ed
in
nitric aci
d.
The
phos
phat
e is
b
rou
gh
t in
to so
lutio
n
as
ort
ho
ph
osp
ha
te.
Aron
oniu
m v
anad
ate
is
adde
d to
th
e acid
ic
ort
ho
ph
osp
ha
te
so
lutio
n.
An
exce
ss
of
amm
oniu
m m
olyb
date
is
ad
ded,
an
d th
e
yello
w h
ete
rop
oly
co
mpl
ex,
moly
div
anadophosp
horic
acid
, is
fo
rmed
. S
pect
ro p
ho
tom
etr
ic
mea
sure
men
t is
m
ade
at
460
nm.
Beer's
la
w
is
report
ed
to
apply
up
to
40
pp
m
phos
phor
us.
Rea
gent
s (a
ll
che
mic
als
-re
ag
en
t gra
de):
Pho
spha
te
Sta
ndar
d:
4.39
37
gram
tw
ice
re
cry
sta
ll iz
ed
po
tass
ium
di
hydr
ogen
phos
phat
e m
ade
to
one
lite
r in
w
ate
r.
1 m
l =
1000
yg
P
.
1.
Anm
oniu
m m
olyb
date
: 5
pe
rce
nt
solu
tion
of
the salt
F i 1
ter
.dis
solv
ed
in
war
m w
ate
r (5
0°C
).
Anm
oniu
m v
anad
ate:
0.
25
pe
rce
nt
solu
tion
prep
ared
by
dis
solv
ing
2.5
gr
ams
of
NH
4\/0
3 in
50
0 m
l of
boili
ng w
ate
r,
coolin
g
the
solu
tion
som
ewha
t, addin
g
20 m
l o
f co
nce
ntr
ate
d n
itric
aci
d
and
dilu
tin
g
to
one
lite
r a
fte
r allo
win
g
the
mix
ture
to
co
ol
to
room
te
mpera
ture
.
Pro
cedu
re
Mix
10
0 m
g of
sam
ple
with
70
0 m
g Li
B02
an
d tr
an
sfe
r to
a
gra
phite
cru
cib
le.
Pre
pare
a
series
of
rock
st
andard
s an
d a
rea
ge
nt
blan
k a
t th
e
sam
e tim
e
in
the
sam
e m
anne
r.
Com
men
ts
1.
If
a to
tal
an
aly
sis
has
been
re
qu
est
ed
, th
e
fusi
on
mad
e fo
r K
and
Na
may
be
used
, pro
vided th
at
the
anticip
ate
d
pe
rce
nt
?2®
5 ^s
n
^9n
enou
gh
so
that
on
ly
an
aliq
uo
t of
the to
tal
so
lutio
n
is su
ffic
ien
t
2.
Fuse
th
e
sam
ples
an
d st
an
da
rds
for
15
min
utes
a
t 95
0°
C.
Pou
r ea
ch
mol
ten
bead
in
to
~ 50
ml
of
H20
whi
ch
conta
ins
7.3
ml
HN
03-
Stir
ma
gn
etic
ally
fo
r 15
m
inute
s.
3.
Add
in
ord
er,
w
ith
adeq
uate
m
ixin
g,
10 m
l o
f 0.
25
perc
ent
amm
oniu
m v
anad
ate
so
lutio
n
and
10 m
l o
f 5
perc
ent
amm
oniu
m m
olyb
date
so
lutio
n.
Tra
nsf
er
to
100
ml
volu
me
tric
fla
sks,
dilu
te
to
mar
k w
ith
H20
an
d m
ix w
ell.
2.
The
colo
r co
mpl
ex w
ill
ultim
ate
ly b
e de
velo
ped
from
the
who
le
sam
ple.
T
here
fore
, 7
.3
ml
of
HN03
is
need
ed
to
con
tro
l th
e a
cid
ity.
Rea
gent
s sh
ould
be
ad
ded
in
the
ord
er
men
tione
d.
If
mol
ybda
te
is
adde
d befo
re
vanadate
, ye
llow
m
oly
bdip
hosp
horic
aci
d
is
form
ed w
ith
the
dang
er
of
a collo
idal
dis
pe
rsio
n
of
amm
oniu
m m
olyb
diph
osph
ate
whi
ch
does
n
ot
dis
appear
on
addi
ng v
anad
ate.
Th
e w
hole
sa
mpl
e is
ta
ken
to
pro
vid
e
0.1
to
5 m
g o
f ph
osph
orus
fo
r 1-
cm ce
lls.
16
4.
Prep
are
a series of standards
as fo
llow
s:
4.
A 2.
5, 5, 10
, and
20 p
pm st
anda
rd,
with approximately
the
same p
H as
the
samples, sh
ould
result.
Diss
olve
3.5 g
LiBO?
in h^
O wh
ich
cont
ains
36
.5 m
l HN
03.
Make to
250
ml vo
lume
with
h^O.
With a
grad
uate
, add
50 m
l to each o
f four 10
0-ml
fl
asks to which
250, 500, 10
00,
and
2000 pg
has
been
adde
d respectively.
Prep
are
the
comp
lex
as in step 3
abov
e.
5.
Allo
w th
e solutions
to stand
over
nigh
t so th
at th
e 5.
So
luti
ons
cont
aini
ng _
> 5
ppm
are
stable at
le
ast
7 inevitable gr
aphi
te p
articles settle to
the
bottom o
f we
eks.
Below
this co
ncen
trat
ion,
color
incr
ease
s th
e flasks.
Meas
ure
the
abso
rban
ce at 460
nm.
slow
ly am
ount
ing
to 2
perc
ent
transmittance
inap
prox
imat
ely
2 weeks.
6.
Prepare
a calibration
curv
e by t
he m
ethod
of le
ast
6.
Rock
standards
are
carr
ied
through
the
proc
edur
e as
squa
res.
Co
mput
e percent
P2®5
^n ^n
e roc'
< co
ntro
ls,
stan
dard
s and
the
unknowns.
Compiled b
y h. Cremer
17
COLO
RIME
TRIC
DETERMINATION
OF SI
LICA
(Ada
pted
from
the
Direct m
icro
dete
rmin
atio
n of silicon
and
aluminum in silicate m
iner
als,
R.
Me
yrow
itz,
U.
S. Ge
ol.
Survey P
rof.
Paper
650-
B, 1969,
p. B1
36-B
139.
)
In m
any
cases, complete an
alys
es are
requ
este
d on v
ery
smal
l ro
ck an
d mineral
samp
les.
Th
e following
procedure
has
been
su
cces
sful
ly u
tilized
in th
e an
alys
is of si
lica
tes
and
phosphates.
Cons
titu
ents
which m
ay b
e determined
instrumentally in
the
resu
ltin
g soluti
on in
clud
e Si02,
A120
3, Total
Fe as Fe
203»
Ti
02»
?2®5
> CaO, Mn
O an
d Mg
O.
In the
silica determination, an
ap
prop
riat
e aliquot
is re
acte
d with ammonium m
olybdate to f
orm
a yellow
sili
co-1
2-mo
lybd
ate
complex, which
is then bu
ffer
ed with tartaric ac
id before r
educ
tion
to
he
tero
poly
mol
ybde
num
blue.
Colo
r intensity
is then compared sp
ectr
opho
tome
tric
ally
to
similarly
trea
ted
rock standard so
luti
ons
ana
perc
ent
Si02 is calculated.
Reagents (a
ll chem
ical
s-re
agen
t gr
ade)
:
LiB02, an
hydr
ous
powder.
HN03,
concentrated.
Ammo
nium
mol
ybda
te so
luti
on:
Diss
olve
3.75
g of ^4)51^07024.4^0
in 35 ml ^0 in a
50 m
l Tri-Pour
beak
er c
ontaining
a Kel-F-covered
magn
etic
stirring b
ar.
Add
5.0
ml 18N ^04.
Stir
un
til
dissolved.
Cool
.Filter through
a Whatman
No.
40 p
aper in
to a
50-ml
volu
metr
ic fl
ask.
Di
lute
to
mar
k.
Tartaric acid,
10 p
erce
nt:
Weigh
20 g
tar
tari
c ac
id.
Diss
olve
in H
20 in
a
200-
ml volumetric flask.
Filter fo
r st
orag
e.
Prep
are
fresh
when sediment ap
pear
s.
Redu
cing
sol
utio
n:
Dissolve 9
.0 g
sodium b
isul
fite
(NaHS03) in 8
0 ml
H2
0 in
a
100
ml Tri-Pour beaker containing
a Kel-F
cove
red
magnetic st
irri
ng b
ar.
In an
othe
r 10
0-ml
Tr
i-Po
ur beaker co
ntai
ning
10
ml H?0
and
magnetic
stir
ring
bar
, di
ssol
ve 0
.7 g
sodium sulfite
(Na2
S03)
. Ad
d 0.
15 g
of l-
amin
o-2-
naph
thol
-4-s
ulfo
nic
acid
to th
e su
lfit
e solution and
stir
until
completely d
isso
lved
. Ad
d the
80 m
l bisulfite
solu
tion
to
the
combined solution an
d mi
x thoroughly.
Filter th
roug
h a
What
man
No.
40 p
aper in
to a
100-
ml vo
lume
tric
fl
ask.
Dilute to vo
lume
with
water
and
transfer to a
plastic
bottle f
or st
orag
e.
Prepare
fresh
daily.
Procedure
1. In
to a bl
ack-
glaz
ed po
rcel
ain
crucible,
weigh
40 m
g rock or
min
eral
powder.
Add
to th
e crucible 350
mg Li
B02.
Th
orou
ghly
mix
the
powd
ers
toge
ther w
ith
a platinum r
od or stainless
steel
spat
ula.
At th
e sa
me time,
weigh
a 35
0-mg
po
rtio
n of L
iB02,
for
use
as a
blan
k, and
carr
y it,
with the
samples, th
roug
h the
whole
procedure.
Comm
ents
This me
thod
has
been us
ed successfully o
n sa
mple
s ra
ngin
g in w
eigh
t from 2
5 to
50
mg.
If
mor
e than th
e analysis of
Si02 is
requested, check
the
appr
opri
ate
procedure
so th
at th
e ne
cess
ary
rock standards
will
be
fused
at th
e same time.
A series of
rock standard m
ater
ials
whose
composition
appr
oxim
ates
that o
f th
e unknowns sh
ould
be
trea
ted
inthe
same
man
ner
so that a ca
libr
atio
n curve
may
be
prepared fr
om t
heir "t
rue"
va
lues
. 18
3. Ca
refu
lly
transfer th
e powder-flux
mixt
ure
to a
graphite crucible o
f the
type
de
scri
bed
in th
e de
term
inat
ion
of Na
and
K.
4. He
at for
15 minutes
in a muffle fu
rnac
e at 9
50°
C.
5. Remove th
e cr
ucib
le from t
he m
uffl
e an
d swirl
it
brie
fly
to cause
the
molten m
ater
ial
to coalesce.
Pour the
melt in
to a
250-
ml Tr
i-Po
ur beaker containing
a Ke
l-F
cove
red
magnetic st
irri
ng bar, 20
0 ml water,
and
10 m
l co
ncen
trat
ed HN03-
Cover
and
mix
on a
magnetic st
irre
r for
at le
ast
5 minu
tes
or until
dissolved.
6. Qu
anti
tati
vely
tra
nsfe
r th
e so
luti
on to
a
250-ml
volumetric flask, carefully
rins
ing
the
beak
er a
nd
maki
ng t
he solution to v
olume
with wa
ter.
7. For
dete
rmin
atio
n of
Si02,
transfer 5-
ml aliquots of
both standards
and
unkn
owns
to
100-ml vo
lume
tric
flasks.
Add
appr
oxim
atel
y 50
ml
wate
r and
mix
by
swirl ing.
8. Ad
d 2.0
ml ammonium m
olyb
date
solution,
swirl, an
d le
t stand
10 m
inut
es.
9. Add
4.0
ml 10 pe
rcen
t tartaric acid and
swirl.
10.
Add
1.0
ml of
th
e Na2S03
/NaHS0
3/l-
amin
o-2-
naph
thol
-4-s
ulfo
nic
acid r
educ
ing
solu
tion
, to
the
mark an
d mix
thor
ough
ly.
Dilute
11.
Let
stand
a minimum
of 30
minutes,
then me
asur
e the
abso
rban
ce at
65
0 nm
, using
water
to s
et t
he
spectrophotometer
to ze
ro.
12.
Weig
ht correct
the
percent
conc
entr
atio
ns of
the
rock
stan
dard
s.
Use
the
corrected
concentrations pl
us th
e absorbance values to
obtain
a sl
ope-
inte
rcep
t linear
equa
tion
. From t
his
equa
tion
, calculate
the
concentrations
of
th
e sa
mple
s.
Weig
ht correct
the
concentrations back to th
e or
igin
al sample w
eight.
If th
e co
ncen
trat
ion
of Si02 in
solution ex
ceed
s that o
f approximately
200
yg/m
l, polymers fo
rm.
Reaction with am
moni
um m
olybdate do
es not
occur.
A 50-mg
samp
le co
ntai
ning
as
much as
68.66
perc
ent
Si02
(NBS 9
9a,
soda f
eldspar) at a 20
0 an
d 25
0 ml
dilu
tion
contains only ~
172
and
175
yg/ml
respectively.
8. The
sili
ca (present as si
lici
c ac
id)
reacts with
molybdate
to fo
rm a
yel
low
sili
co-1
2-mo
lybd
ate
complex,
9. Tartaric acid ac
ts as
a
buffer to adjust th
e pH in
prep
arat
ion
for
the
next
st
ep.
10.
The
reducing s
olution
reac
ts with th
e ye
llow
si
lico
-12-
moly
bdat
e complex
and
redu
ces
it to
hete
ropo
ly m
olybdenum
blue
.
11.
Color
complex
is st
able
for
several
days
.
Compiled by S.
Ne
il, 19
CO
LOR
IMET
R1C
T
i02
(Ada
pted
fr
om
Rap
id
An
aly
sis
of
Sili
ca
te,
Carb
onate
, an
d P
hosp
hate
R
ocks
-
Rev
ised
E
ditio
nby
Le
onar
d S
hapiro,
Ge
olo
gic
al
Sur
vey
Bu
lletin
14
01)
Whe
n T
iro
n
(dis
od
ium
-l,2
-dih
yd
roxylb
en
ze
ne
-3,5
-dis
ulfo
na
te)
is
adde
d to
tita
nia
(T
i02
),
a ye
llow
co
lor
is
prod
uced
. F
err
ic
iro
n,
an
inte
rfe
rer,
a
lso
re
act
s w
ith
Tiro
n
to
form
a
purp
le so
lutio
n
whi
ch
mus
t be
deco
lorize
d
by
reduct
ion
with
so
dium
d
ith
ion
ite
. An
a
liqu
ot
of
a Li
B02
fu
sion
dis
solv
ed
in
4 perc
ent
HN03
is
us
ed
to
deve
lop
the
com
plex
.
Rea
gent
s (a
ll
chem
icals
-reagent
gra
de
):
Tiro
n
(dis
od
ium
-l,2
-dih
yd
roxylb
en
ze
ne
-3,5
-dis
ulfo
na
te):
D
ry
pow
der.
Bu
ffe
r so
lutio
n:
Dis
solv
e 8
0 g
of
amm
oniu
m a
ceta
te
NH
4C2H
302
and
30 m
l of
gla
cia
l a
ce
tic
aci
d
in
2 lite
rs
dis
tille
d w
ate
r.
Filte
r.
Sod
ium
d
ith
ion
ite
, ^$204
(a.k
.a.
sodi
um hydro
sulfite):
D
ry
pow
der.
Pro
cedu
reC
omm
ents
1.
Tra
nsf
er
15
ml
port
ions
of
bla
nk,
ro
ck
standard
s,
and
sam
ples
to
a
serie
s of
150
ml
beake
rs.
2.
Use
a
mea
surin
g sc
oop
to
add
ap
pro
xim
ate
ly
125
mg
of
Tiro
n
pow
der
to
each
b
ea
ker.
3.
Add
50 m
l o
f buffer
so
lutio
n
to
each
b
ea
ker.
4.
Use
a
spatu
la
to
add
10-2
0 m
g so
dium
dithio
nite
to
the
bla
nk
so
lutio
n
as
well
as
to
the
sta
nd
ard
so
lutio
ns.
Mix
g
en
tly w
ith stirr
ing r
ods.
5.
Set
th
e
spe
ctro
pho
tom
eter
at
430
nm
and
adju
s.t
to
zero
ab
sorb
ance
w
ith
h^O
. R
ead
the
abso
rban
ce of
the
so
lutio
ns.
6.
Add
dithio
nite
pow
der
to
the
next
10
beake
rs.
One
by
on
e, stir
gently,
pour
in
to
the
ab
sorp
tion
cell,
and
mea
sure
ab
sorb
ance
.
1.
So
lutio
ns
used
a
re
thos
e pre
pare
d fo
r th
e co
lorim
etr
ic
de
term
ina
tion
o
f S
i02,
or
tho
se
prep
ared
fo
r K
and
Na,
w
hen
a m
ore
ap
pro
pria
te
aliq
uo
t is
us
ed.
2.
The
form
ula
fo
r T
iro
n
isC6
H2(
OH
)2(S
02O
Na)
2.H
20.
The
nam
e T
iro
nw
as
adop
ted
beca
use
of
its re
actio
n w
ith
both
tita
niu
man
d iro
n.
3.
The
solu
tion
mus
t be
b
uff
ere
d
at
pH
4.7
so th
at
sodi
um
dith
ion
ite
re
duce
s iron
to
dest
roy
the
purp
le fe
rric
iro
n
com
plex
.
4.
Vig
orou
s m
ixin
g
caus
es
sulfur
to
pre
cip
ita
te.
6.
The
purp
le
colo
r o
f th
e
iro
n
com
plex
fa
des
to
the
yello
w
colo
r o
f th
e tita
niu
m
com
plex
. 20
7. Re
peat
step 6
with
the
remainder
of t
he s
olut
ions
taken
10 a
t a
time
.
8. Treat
the
rock
st
anda
rds'
data b
y th
e method o
f le
ast
squares.
Calc
ulat
e percent
Ti02 in th
e unknowns.
9. Us
e th
e data t
o correct
apparent A
1203 v
alues
as
well as
to
repo
rt pe
rcen
t
7. A
time li
mit
between
dith
ioni
te ad
diti
on an
dabsorbance r
eading is necessary
beca
use
iron
will
be
oxid
ized
by
air.
With time,
the
purp
le co
lor
of t
he
iron co
mple
x wi
ll re
appe
ar.
Comp
iled
by
M.
Crem
er
21
REFE
RENC
ES
Shap
iro,
L.
, 1975,
Rapid
Anal
ysis
of
Silicate,
Carbonate, an
d Phosphate
Rock
s Re
vise
d Ed
itio
n:
Geol
ogic
al Survey
Bull
etin
1401.
Yoe, J.
H.,
and
Armstrong, A. R.,
1947
, Colorimetric determination
of t
itanium
with
diso
dium
-l,2
-dih
ydro
xylb
enze
ne-3
,5-d
isul
fona
te:
Anal
. Chemistry, v. 19,
p. 100-102.
22
GRAV
IMET
RIC
ANALYSIS O
F AX
INIT
E, A
BORO
N MI
NERA
L (From
an un
publ
ishe
d me
thod
de
vise
d by F
rank G
rimaldi)
Whil
e ax
init
e is
a silicate m
iner
al,
boron, a ma
jor
cons
titu
ent,
complicates
the
anal
ysis
of
si
lico
n, ir
on,
and
aluminum.
At the
begi
nnin
g of t
he a
nalysis, boron
is re
move
d wi
th methanol as
8(0^3)3.
Otherwise, the
analysis
proceeds in the
usua
l manner.
Boro
n is
de
term
ined
by
elution
and
titr
atio
n with mannitol.
The
foll
owin
g me
thod
, although w
ritt
en to
handle small
samp
les,
can
be a
mend
ed w
hen
suff
icie
nt s
ampl
e is available.
Procedure
1. We
igh
0.20 g
sample into a
small
prew
eigh
ed pl
atin
um c
ruci
ble.
Dry
to constant w
eigh
t at
10
5 *
5°C
and
comp
ute
percent
2. Mi
x the
dried
samp
le w
ith
one
gram N
a2C0
3.
Fuse in the
usual
manner.
3.
Leac
h th
e cru
cib
le
and
its
con
ten
ts
ove
rnig
ht
with
25
m
l ^0
in
a
75
ml
pla
tinu
m e
vap
ora
ting
dis
h.
Bre
ak
up
the
ca
ke,
rem
ove
and
rinse
the cru
cib
le,
insp
ect
it
for
ad
he
rin
g p
art
icle
s,
and
add
with
ca
re
5 m
l HC
1 to
th
e co
vere
d d
ish
. W
hen
the re
act
ion
has
sub
sid
ed
, ad
d 5
ml
meth
anol.
4.
Deh
ydra
te
the
co
nte
nts
o
f th
e
dis
h
on
the
stea
m
bath
, bre
aki
ng
up
lum
ps,
un
til
the
od
or
of
Cl~
ca
n no
lo
ng
er
be
dete
cted.
5.
Cool.
Add
1.5
m
l H
C1.
B
ring
the
a
cid
in
co
nta
ct w
ith
all
the
solid
s.
Let
sta
nd
10
m
inu
tes.
W
ash
the
sid
es
and
cove
r w
ith
1:2
0
HC1
so
lutio
n.
Add
19
ml
H20
, heat
and
dis
solv
e
the
sodi
um chlo
ride.
Then
ad
d 5
ml
Cf^
OH
an
d d
eh
ydra
te
again
.
6.
Rep
eat
step
5 ag
ain
with
th
e
exc
eptio
n
of
the
a
dd
itio
n
of
CI^
OH
. F
ilte
r as
so
on
as
poss
ible
usi
ng
7 cm
S
and
S bla
ck
rib
bo
n filter
pa
pe
r.
Was
h w
ith
cold
1:
20
HC1
and
fin
ally w
ith
hot
H?0
. U
se
drop
s o
f 0.
005
perc
ent
met
hyl
oran
ge
on
the filter
pape
r to
te
st
for
rem
oval
o
f acid
, i.e.
un
til
the
yello
w colo
r appears
.
7.
Ret
urn
filtra
te
to
dis
h.
Add
5 m
l C
f^O
H.
Eva
pora
te
to
dry
ness
. R
epea
t st
ep 6,
bu
t us
e M
unkt
ell
00
pape
r an
d ad
d pa
per
pu
lp
to
the solu
tion
be
fore
filtering.
Wip
e d
ish
w
ith
smal
l pi
eces
of
hard
ened
filter
pape
r an
d ad
d th
e pi
eces
to
th
e filter.
8.
Fol
d bo
th filter
pape
rs
into
th
e fu
sio
n
cru
cib
le
whi
ch
was
pre
vio
usly
cl
eane
d on
th
e o
uts
ide
, ig
nited,
coole
d,
and
wei
ghed
. Ig
nite
to
co
nst
ant
we
igh
t a
t 10
50°C
.
9.
Pro
ceed
w
ith
rem
ain
der
of
the
analy
sis
as
set
fort
h
in
Cla
ssic
al
An
aly
sis:
Th
e M
ain
Port
ion,
rem
embe
ring
to
sca
le
dow
n if only
0.
20
g w
as
used
. Fe
203,
A1
203,
T
i02,
MnO
, C
aO,
MgO
, th
e alk
alie
s,
f^O
, an
d Fe
O m
ust
be
de
term
ine
d.
A se
para
te
po
rtio
n
is
used
fo
r bo
ron s
ee
Dete
rmin
atio
n o
f B
oron
in
S
ilicate
s.
Com
pile
d by
M.
Cre
mer
23
REFE
RENC
ES
Deer
, W.
A.,
Howie,
R. A.
, an
d Zu
ssma
n, J.,
1965
, Ro
ck Forming
Minerals:
London,
William
Clowes an
d So
ns,
Ltd.,
v. 1,
p. 32
0-327.
Hill
ebra
nd,
W. F.,
Lund
ell,
G.
E.F.
, Br
ight
, H.
A.,
and
Hoffman, J.
I.,
1953,
Appl
ied
inorganic
analysis:
2d e
d:
New
York,
John Wiley
and
Sons
, p. 750-753.
24
ANAL
YSIS
OF
A
CHRO
ME
SP
INE
L (f
rom
an
u
np
ub
lish
ed
m
etho
d devi
sed
by
Fra
nk
K.
Grim
ald
i)
Thi
s m
etho
d a
pp
lies
specific
ally to
situations
whe
re
no
pro
visi
on
need
be
m
ade
to
dete
rmin
e
Mn,
N
i ,
Zn,
V,
an
d Ti
be
caus
e th
e se
miq
ua
ntita
tive
sp
ec r
ep
ort
sh
ows
thes
e el
emen
ts
to
be
pre
sent
at
conce
ntr
atio
ns
belo
w
0.1
perc
ent
each
. W
hile
th
e m
etho
d is
se
mi-m
icro
, it
may
be
alte
red
a
pp
rop
ria
tely
whe
n suffic
ient
sam
ple
has
been
su
bm
itte
d.
Si0
2 an
d A
1203
ar
e dete
rmin
ed g
ravim
etr
ica
lly,
while
C
r an
d Fe
ar
e d
ete
rmin
ed
colo
rim
etr
ically
.
Rea
gent
s (a
ll
che
mic
als
-re
ag
en
t gra
de):
Sta
ndar
d C
hrom
ate
Sto
ck
Solu
tion:
Dis
solv
e
0.56
56
g of
dry
NB
S 13
6 I^
C^O
y in
2
perc
ent
w/v
Na
OH
and
mak
e to
vo
lum
e w
ith
2 p
erc
en
t Na
OH
in
a 20
0 m
l flask.
1 m
l =
1000
Mg
C
r.
Sta
ndar
d C
hrom
ate
solu
tion
for
ca
libra
tio
n
curv
e:
Take
10
ml
of
the
st
ock
so
lutio
n
and
dilu
te
to
100
ml
with
2
pe
rce
nt
NaO
H.
1 m
l =
lOO
yg
Cr.
NaOH
w
ash
solu
tion:
mak
e 1
lite
r 1
pe
rce
nt
w/v
.
NaOH
so
lutio
n
2 perc
ent
w/v
: F
or
use
in
mak
ing
sta
nd
ard
s,
mak
e on
e lite
r.
CHRO
MIU
M:
Pro
cedu
re
1.
Fuse
0.
050
g sa
mpl
e w
ith
1.5
g N
a202
in
a
zirc
oniu
m cru
cib
le.
Cov
er
with
a
wat
ch
gla
ss,
and
add
25
ml
of
H20
. Le
t st
and
to
dis
inte
gra
te
the
me
lt, stirr
ing
occasio
nally
. W
arm
if
ne
cess
ary
, b
ut
if re
act
ion
is
vio
lent,
quen
ch
the
cru
cib
le quic
kly
in
co
ld
H20
.
2.
Qu
an
tita
tive
ly t
ran
sfe
r th
e
con
ten
ts
to
a 10
0 m
l beake
r.
The
volu
me
at
this
poin
t sh
ou
ld
be ~
50 m
l.
3.
Dig
est
th
e
so
lutio
n
on
the
stea
m
bath
o
vern
igh
t to
d
est
roy
the
pe
roxi
de
an
d to
m
ake
the
pre
cip
itate
filte
rab
le.
4.
Filte
r in
to
a 15
0 m
l be
aker
th
rough
a sm
all
Wha
tman
N
o.
40 f
ilte
r pa
per
pre
viousl
y w
ashe
d w
ith
1 perc
ent
NaOH
so
lutio
n.
Tra
nsf
er
and
was
h th
e pre
cip
itate
w
ith
1 p
erc
en
t Na
OH,
colle
cting
the
was
hes
with
th
e m
ain
so
lutio
n.
The
volu
me
sho
uld
be
ab
out
75
ml
at
this
poin
t.
If
any
Fe(O
H)3
pa
sses
th
rough
the
filter
in
the collo
idal
sta
te,
dig
est
th
e
solu
tion
(cov
ered
b
ea
ker)
on
th
e st
eam
bat
h until
the
pre
cip
itate
settle
s.
Filte
r a
ga
in,
colle
cting
the
filtra
te
in
a 10
0 m
l vo
lum
etr
ic flask
and
was
hing
w
ith
1 perc
ent
NaOH
solu
tion.
Mak
e to
vo
lum
e w
ith
1 perc
ent
NaOH
so
lutio
n.
5.
Mix
an
d re
serv
e.
25
6. For
the
stan
dard
curve,
tran
sfer
0,
1, 3,
5,
and
10 m
l aliquots of
the
sta
ndard
solu
tion
of
100
yg/ml
to 100
ml
volu
metr
ic fl
asks
. Make to v
olum
e wi
th 2
pe
rcen
t Na
OH solution and
mix.
7. Transfer 10
ml
aliq
uots
of
the u
nknowns
to a
seri
es of
100
ml
volu
metr
ic flasks.
Make to
volume
with 2
percent
NaOH
solu
tion
.
8. De
term
ine
the
abso
rban
ce of e
ach
solu
tion
at
37
0 nm
in
1 cm
cells,
usin
g H20
as a
reference.
9. Determine
the
Cr co
nten
t of
the
samples
using
the
stan
dard
cur
ve.
26
SIL
ICA
, AM
MO
NIA
G
RO
UP,
C
ALC
IUM
, AN
D M
AG
NE
SIU
M:
Pro
cedu
re
1.
Sin
ter
for
30 m
inut
es
at
500°
±
20°C
, 0.2
g
sam
ple
mix
ed w
ith
2 g
Na?
02
in
a sm
all
(co
vere
d)
Pt
cru
cib
le
(~10
ml )
.
2.
Coo
l an
d pl
ace
cru
cib
le
in
a 50
ml
Pt
dis
h.
Add
20 m
l \\2
®>
cove
r w
ith
a te
flo
n
wat
ch
gla
ss,
and
plac
e on
st
eam
bat
h to
d
isin
teg
rate
m
elt
and
dest
roy
pe
roxi
de
.
3.
Acid
ify w
ith
~3
ml
HC
104
and
add
3 m
l H
C10
4 in
exce
ss.
Rem
ove
cru
cib
le.
If
gra
ins
of
unde
com
pose
d m
ine
ral
are
pre
sen
t, filter
the
so
lutio
n
and
rese
rve
it.
The
resi
du
e
and
pape
r m
ust
be
ashe
d an
d re
sin
tere
d w
ith
4.
Eva
pora
te
exce
ss
H20
on
st
eam
bath
. H
eat
on
hot
pla
te
to
fum
es
of
HC
104.
Ad
d 25
m
l of
H20
and
heat
to
dis
solv
e sa
lts.
5.
Filte
r th
rou
gh
a
5.5
or
7 cm
W
hatm
an
No.
40
paper,
co
llectin
g filtra
te
in
anot
her
50 m
l P
t dis
h.
Was
h w
ith
H£0
an
d tr
an
sfe
r pa
per
and
pre
cip
itate
to
a
sma
ll w
eigh
ed ~
10 m
l P
t cru
cib
le.
Set
a
sid
e.
6.
Eva
pora
te
the
filtra
te
on
the
stea
m b
ath
and
bring to
fu
mes
of
HC
104
ag
ain
.
7.
Add
25
ml
^0
. A
gain
heat
to
dis
solv
e
solu
ble
salts.
Filte
r as
b
efo
re,
colle
cting filtra
te
in
a 50
m
l beake
r.
Com
bine
re
sidue w
ith
that
de
scrib
ed
in
st
ep
5 ab
ove.
8.
Aft
er
ashi
ng th
e
papers
, ig
nite
th
e
two
resi
dues
to
con
sta
nt
we
igh
t at
1050
°C.
9.
Add
to
the
resi
du
e
a fe
w
drop
s H
C10
4 an
d a
few
m
l HF
. E
vapo
rate
th
e so
lutio
n
and
fum
e o
ff
the
H
C10
4.
Ign
ite
an
d w
eigh
.
Com
men
ts
1.
Pla
ce
cru
cib
le w
ith
its
con
ten
ts
in
a co
ld m
uffle
an
d bring to
te
mp
era
ture
.
3.
HC
104
is
used
in
stead o
f HC
1 -
see
com
men
t 4
4.
De
hyd
ratio
n
of
Si0
2 is
fa
r m
ore
com
plet
e w
ithH
C10
4 th
an
with
H
C1.
T
his
is
achi
eved
in
a
sin
gle
opera
tion.
The
sa
lts
are
mus
hy b
ecau
se
HC
104
does
no
t go
to
dry
ness
.
6.
Filtr
ate
co
nta
ins
Fe,
M
g,
Ca,
N
i, A
l,
som
e S
i,
and
Cr,
8.
The
resi
due
is
impu
re
Si0
2.
9.
SiF
4+
. Th
e lo
ss
in
weig
ht
equa
ls
27
10.
Fuse with K2S207 an
y re
sidu
e fr
om s
tep
9.
Keep
the
crucible co
vere
d and
heat slig
htly
above
the
melt
ing
point
of potassium
pyrosulfate
so th
at fe
w fumes
of SC
>3 e
scape.
Fina
lly,
heat th
e crucible to
low
bott
om r
edness.
Cool
, dissolve in a
few
ml H20
acid
ifie
d wi
th a
few
drops
HC1
and
add
to the
main
solution.
~~
11.
Add
to th
e main solution a
few
ml of
H2S03 t
ore
duce
Cr.
Boil
out
the
S02
and
add
1 ml HN
03.
Boil
again
to r
eoxidize Fe
.
12.
Prec
ipit
ate
the
ammonia
group
by f
ollo
wing
the
procedure
outlined in C
lass
ical
Analysis:
the
Main
Po
rtio
n-th
e Ammonia
Group; ho
weve
r, scale
down
volumes, glassware, filter paper
reagents,
etc.
, to
fit
the
semi-micro si
tuat
ion.
Th
e fi
ltra
te w
ill
be in
a 150
ml be
aker
at this po
int.
Digest on
st
eam
bath
. Reserve
the
filt
rate
for
Ca a
nd M
g.
13.
Dissolve the
precipitate
in a
small
excess o
f HC
1 an
d repeat th
e NfyOH
prec
ipit
atio
n, filtration,
and
washing.
Combine
the
filtrate w
ith
that o
f st
ep 12
.
14.
Agai
n di
ssol
ve t
he p
recipitate in
a
small
excess o
f HC
1 in
a
50 m
l be
aker
. Ad
d 2
ml HC104
and
take to
fu
mes.
15.
Add
1 ml HC1
drop
wise
down t
he si
de o
f the
cove
red
beak
er w
hile
fu
ming
str
ongl
y for
at least
15 m
inut
es.
Repe
at th
e pr
oces
s at
least
four ti
mes
more.
If
during th
e fu
ming m
uch
HC104
^s lo
st b
y evaporation,
add
more.
16.
When volatilization is co
mple
te,
i.e. when the
fumi
ng
HC104
fail
s to
bring
out
the
dich
roma
te color, wash
off
cover
and
stir
ring
rod,
bring
to f
umes
again.
Add
25 m
l H2
0 and
heat to di
ssol
ve sa
lts.
10.
The
residue, if any, consists of those
elements now
in
the
main so
luti
on;
i.e. Fe
, Mg
, Ca
, Ni
, Al,
Cr.
17.
Add
30 m
l of
h^
O and
dige
st to
di
ssol
ve sa
lts.
Pr
ecip
itat
e ag
ain
with NfyOH
in th
e usual
manner.
Digest again
on steam
bath and
adju
st p
H again
if
necessary.
12.
The
prec
ipit
ate
is C
r, Fe
, Al,
and
part
of
the
Ni.
The
digestion
of t
he f
iltr
ate
will
determine
if any
R203 c
rept th
roug
h th
e filter paper.
If
precipitate
appears,
it must be
filtered
off
and
adde
d to
th
e rest of th
e R203 precipitate.
13.
If th
ere
is a
delay
in di
ssol
ving
the
precipitate,
A1(OH)3
may
fail to completely d
isso
lve.
If
the
solu
tion
of th
e dissolved
precipitate
is turbid,
i.e.
A1
(OH)
3 ha
s passed th
roug
h the
filter p
aper,
heat
the
solu
tion
on
th
e steam
bath
.
15.
Chro
mium
is removed
as ch
romy
l-ch
lori
de
(Cr02Cl2).
HC104
should not
be co
mple
tely
vo
lati
lize
d be
caus
e ch
romi
c ac
id is ea
sily
red
uced
by
HC1
and
must be
ox
idiz
ed to
the
hexa
vale
nt state
by
fumi
ng HC
104.
HC
1 is ad
ded
so sl
owly
to
perm
it th
e re
oxid
atio
n of Cr
to
occu
r as
qui
ckly
as
possible.
16.
If the
solution is gr
een,
not
only
is Cr still
pres
ent,
bu
t it is in it
s reduced
+3 st
ate.
17.
The
prec
ipit
ate
is f
ilte
rabl
e when it clots.
28
18.
Filte
r th
rou
gh
sm
all
doub
le filter
pape
rs
(no
. 41
insid
e
589
white
ribbon),
an
d w
ash
with
h
ot
2 p
erc
en
t N
fyC
l. D
ige
st
the filtra
te.
If
mor
e R
203
form
s, filter
and
com
bine
th
e
pre
cip
itate
with
th
e
mai
n ^63
po
rtio
n.
Re
ject
th
e filtra
te.
19.
Ign
ite
th
e
R20
3 to
co
nst
ant
weig
ht
and
fuse
w
ith
po
tass
ium
p
yro
su
lfa
te.
Add
1 m
l HC
1 an
d h^
O to
dis
solv
e
the
me
lt.
20.
Mak
e th
e solu
tion
to
250
ml
in
a vo
lum
etr
ic flask;
on
a 5
ml
aliq
uo
t,
de
term
ine
Fe
by
o-p
henanth
rolin
e.
21.
Rem
ove
a 50
ml
aliq
uo
t fr
om
th
e
250
ml
abov
e.N
eu
tra
lize
w
ith
NaOH
u
ntil
a fa
int
pre
cip
ita
te ju
st
sta
rts
to
form
. D
isch
arge
th
e
pre
cip
itate
w
ith
a fe
w
drop
s of
dilu
te
HC
1.
22.
Hea
t th
e
abov
e solu
tion
and
pour
it
into
20
ml
of
ho
t 10
perc
ent
w/v
Na
OH co
nta
inin
g
0.15
m
l of
30
pe
rce
nt
H20
2«
Rin
se
the solu
tion
beak
er w
ith
hot
1 perc
ent
NaO
H.
23.
Dig
est
th
e m
ixtu
re fo
r at
lea
st
thre
e
hour
s to
dest
roy
H20
2 an
d to
a
llow
th
e h
ydro
xid
e
pre
cip
ita
te
to
form
an
d clo
t.
24.
Filte
r,
dis
card
th
e p
recip
ita
te,
and
mak
e th
e .
filtra
te
to
100
ml
in
a vo
lum
etr
ic fla
sk.
Det
erm
ine
chro
miu
m
as
chro
mat
e.
25.
Use
th
e filtra
te
in
the
150
ml
beak
er
(ste
ps
12
and
13)
to
pre
cip
itate
ca
lciu
m
and
mag
nesi
um
in
the
us
ual
man
ner
(see
Cal
cium
an
d M
agne
sium
-Cla
ssic
al
An
aly
sis:
M
ain
Po
rtio
n).
26.
If desi
red,
iso
late
C
aSO
/j a
fte
r d
isso
lvin
g
Mg2
?207
in
th
e
usua
l m
anne
r.
(See
C
alci
um '
Rec
over
y fr
om
Ma
gn
esi
um
-Cla
ssic
al
An
aly
sis:
P
ort
ion).
18.
See
step
1.
Cla
ssic
al
An
aly
sis:
Th
e M
ain
Po
rtio
n
the
Amm
onia
G
roup
.
19.
Pre
cip
ita
te
conta
ins
Fe,
A
l,
Ni,
Ti,
and
som
e C
r.
Sin
ce
the
re
is litt
le
Ti
and
Ni,
they
are
no
t dete
rmin
ed.
20.
See
pro
cedure
fo
r Fe
by
O
-phenanth
rol i
ne
.
21.
Som
e C
r m
ay still
rem
ain
in
the
R
203
gro
up
; it
is
de
term
ine
d spectr
ophoto
metr
ically
as
ch
rom
ate.
23.
The
pre
cip
itate
co
nta
ins
all
the
elem
ents
as
hyd
roxi
de
s ex
cept
th
e
Cr
whi
ch
rem
ains
in
so
lutio
n
24.
See
pro
cedure
fo
r co
lorim
etr
ic
Cr.
A
1203
is
d
ete
rmin
ed
by
diffe
rence
in
the
usua
l m
anne
r.
25.
Rea
gent
s,
etc
. m
ust,
of
cours
e,
be
sca
led
do
wn
to
acco
mm
odat
e th
is
sem
imic
ro
met
hod.
Su
ch
a sm
all
amou
nt o
f ca
lciu
m m
ay n
ot
pre
cip
itate
. N
i, a
lso
pre
sent
in
the filtra
te,
does
not
pre
cip
ita
te
with
either
Ca
or
Mg
whe
n oxa
late
is
pre
sent.
Mai
n
Com
pile
d by
M
. C
rem
er
29
GR
AV
IME
TRIC
D
ETE
RM
INA
TIO
N
OF
PHO
SPH
OR
US
Whe
n su
ffic
ien
t sa
mpl
e is
a
va
ilab
le
and
the
anticip
ate
d
conce
ntr
atio
n
of
?2®
5 is
3
pe
rce
nt
or
mor
e, it
is
we
ll to
dete
rmin
e
phos
phor
us
gra
vim
etr
ically
as
M
g?
??
^-
The
sam
ple
is
fuse
d w
ith
a m
ixtu
re of
Na£
C03
an
d N
a202
» an
d silic
a
is
rem
oved
fo
llow
ing
a
cid
ific
atio
n
with
HN
03
and
de
hyd
ratio
n.
The
phos
phor
us
is
then
se
para
ted
by p
recip
itation
with
am
mon
ium
m
oly
bd
ate
, fo
llow
ed
by d
isso
lutio
n
with
N
H^H
; th
en
a do
uble
p
recip
ita
tio
n
is
mad
e as
M
gNH4
P04
with
su
bseq
uent
ig
nitio
n
to
Rea
gent
s (a
ll
che
mic
als
-re
ag
en
t g
rad
e):
M07
024-
4H20
(A
mm
oniu
m m
oly
bdate
):
30
perc
ent
(w/v
) aq
ueou
s solu
tion,
filtere
d.
Mag
nesi
a m
ixtu
re:
Dis
solv
e
50
g M
gCl2
-6H
20
and
100
g NH
4C1
in
500
ml
H20
. Ad
d NH
40H
in slig
ht
exce
ssan
d allo
w
to
sta
nd
ove
rnig
ht.
Mak
e slig
htly acid
ic w
ith
HC1
, d
ilute
to
1
lite
r,
and
store
in
a
gla
ss-s
top
pe
red
Pyr
ex b
ott
le.
Citric
aci
d,
2 M
: D
isso
lve
38
g
citric
aci
d
in
70 m
l H
20.
Dilu
te
to
100
ml.
Filte
r.
Sto
re
in
Pyr
ex bottle
.
Pro
cedu
re
Com
men
ts
1.
In
a co
vere
d p
latin
um
cru
cib
le,
sin
ter
a 0.5
g
sam
ple
and
0.1
g S
i02
with
1
g Na
2C03
an
d 1
g N
a202
at
500°
C
in
a m
uffle
fu
rnace
fo
r 1
hour.
R
emov
e fr
om m
uff
le
and
allo
w
to
coo
l.
2.
Add
a fe
w
ml
H20
to
th
e cru
cib
le
and
allo
w
the m
elt
to
leac
h fo
r a
few
m
inu
tes.
T
ransf
er
the
con
ten
ts of
the
cru
cib
le,
as
com
ple
tely
as
poss
ible
, to
a
larg
e
(~
300
ml)
pla
tinu
m dis
h.
Cov
er.
Add
5-10
ml
HN03
to
th
e cru
cib
le,
cove
r an
d le
t st
and
a fe
w
min
utes
to
re
act
w
ith
any
of
the
fusi
on
still
in
the
cru
cib
le.
3.
With
th
e
pla
tinu
m
dis
h
cove
red
with
a
wat
ch
gla
ss,
pi p
et
25 m
l 1
+ 1
HN
03
into
th
e
dis
h
thro
ug
h
the
spo
ut.
W
hen
react
ion
ceas
es,
rem
ove
the
cove
r an
d ad
d th
e
conte
nts
of
the cru
cib
le
to
the dis
h,
ca
refu
lly
po
licin
g
and
was
hing
th
e cru
cib
le.
1pro
vides
an
oxid
izin
g
atm
osph
ere
with
in
the
cru
cib
le,
bu
t a
tta
cks
pla
tinu
m a
t te
mp
era
ture
s ab
ove
50
0°.
Si
02
is
adde
d to
in
sure
co
mpl
ete
rem
oval
of
F.
HC1
and
H2S
04 m
ust
be
avoi
ded
as
they
tend
to
reta
rd
the
pre
cip
ita
tio
n.
of
amm
oniu
m
phos
phom
olyb
date
30
4.
Cov
er
the
d
ish
an
d heat
on
the
stea
m b
ath
un
til
rea
ctio
n
sto
ps.
R
inse
th
e co
ver
and
sid
es
of
the
dis
h
with
a
little
w
ate
r.
Sup
port
th
e w
atch
gla
ss
with
a
gla
ss tr
iangle
an
d d
eh
ydra
te
as
in
the
us
ual
silic
a
de
term
ina
tion
.
5.
Coo
l th
e
dis
h slig
htly.
Add
to it
10 m
l co
nce
ntr
ate
d
HN03
an
d le
t st
and,
co
ld,
10 m
inute
s.
Was
h co
ver
and
sid
es
of
dis
h
with
5
perc
ent
HN
03.
Add
wate
r to
ab
out
70 m
l. C
over
th
e
dis
h
and
dig
est
on
th
e
stea
m
bath
u
ntil
the
sa
lts
are
dis
solv
ed
.
6.
Filte
r w
hile
still
war
m
thro
ugh
11
cm
Bla
ck
Rib
bon
pape
r in
to
a 60
0 m
l beake
r.
Was
h d
ish
an
d filter
seve
ral
times
w
ith
5 p
erc
en
t H
N03
. Th
en
was
h th
e
filter
with
h
ot
wate
r u
ntil
a dr
op o
f dilu
ted
met
hyl
oran
ge
on
the
filter
ind
ica
tes all
aci
d
has
been
re
mov
ed;
i.e
. th
e
pape
r tu
rns
from
red
to
ye
llow
-ora
ng
e.
7.
Pla
ce
beak
er
con
tain
ing
th
e filtra
te
on
the
st
eam
b
ath
. C
over
an
d ke
ep
war
m
seve
ral
hour
s to
dest
roy
any
pyro
phos
phat
e p
rese
nt.
8.
Pla
ce
the
filter
conta
inin
g th
e
impu
re silic
a
in
the
pla
tinu
m cru
cib
le.
Bur
n o
ff
the
pape
r a
t a
low
te
mp
era
ture
in
th
e m
uffle
, th
en
ignite
at
1000
°C.
9.
Tre
at
the
silic
a w
ith
seve
ral
drop
s of
wa
ter,
1
drop
H
N03
, 3
drop
s H
C10
4,
and
seve
ral
ml
HF.
E
vap
ora
te
to
dryn
ess
on
the
hot
pla
te.
Fuse
th
e
rem
ain
ing r
esi
due w
ith
0.5
g ^2
^03
. D
isso
lve
the
fusi
on
in
5
ml
HN
03
and
add
to
the
mai
n solu
tion
in
the
beake
r.
10.
Add
25
g N
fyt^
, dilu
te
to
300-
400
ml
and
stir
todis
solv
e all
the
n
itra
te.
Add
HN03
as
ne
cess
ary
tom
ake
the
so
lutio
n
5 p
erc
en
t in
H
N03
.
4.
See
Cla
ssic
al
Analy
sis:
Th
e M
ain
Port
ion.
10,
Pho
spha
te
sho
uld
be
p
rese
nt
as
ort
ho
ph
osp
ha
te
in
ord
er
to p
recip
ita
te w
ith
moly
bdate
.
It
is
unne
cess
ary
to
wei
gh
the silic
a
as it
is
mere
ly
be
ing
re
mov
ed,
no
t d
ete
rmin
ed
.
Me
tal-fo
rmin
g
phos
phat
es slig
htly so
lub
le
in
aci
d
are
le
ft
with
th
e silic
a,
and
the
phos
phor
us
is
reco
vere
d
by d
rivin
g o
ff
SiF
4.
In
the
next
st
ep,
phos
phor
us w
ill
be
sep
ara
ted
fr
om
in
terf
erin
g
elem
ents
by
pre
cip
itation
as
amm
oniu
m
phos
phom
olyb
date
in
a
cid
m
ediu
m
prep
ared
in
th
is
step,
31
11.
Hea
t th
e so
lutio
n
to
appro
xim
ate
ly 9
0°C
. W
hile
11
. stirr
ing
, ad
d 10
0 m
l am
mon
ium
mol
ybda
te solu
tion.
Rem
ove
from
he
at.
S
tir
fre
qu
en
tly u
ntil
cool
an
d le
t st
an
d overn
ight.
12.
Filte
r th
rou
gh
15
cm
W
hatm
an
No.
42
p
ap
er,
colle
cting
12.
filtra
te
in
800
ml
be
ake
r.
Was
h pre
cip
itate
th
oro
ug
hly
with
2
pe
rce
nt
HN
03.
It
is
not
nece
ssar
y to
p
olic
e
the p
recip
ita
tio
n
beak
er
at
this
tim
e.
13.
Whe
n th
e filter
has
tho
rou
gh
ly
dra
ined,
was
h th
ep
recip
ita
te
from
th
e
fun
ne
l w
ith
wat
er
back
in
to
the
600
ml
pre
cip
itation
beake
r.
Pla
ce
the
be
aker
un
der
the fu
nnel.
14.
Dis
solv
e
the pre
cip
itate
by
was
hing
ar
ound
th
e
edge
14
. of
the
filter
with
dr
opw
ise
ap
plic
atio
n of
1 +
2 N
H^H
, colle
cting th
e w
ashi
ngs
in
the
600
-ml
beak
er
con
tain
ing
th
e pre
cip
itate
. W
ash
the filter
pape
r five
tim
es
with
5
pe
rce
nt
Nhty
OH,
th
en
seve
ral
times
w
ith
ho
t w
ate
r, fin
ally w
ith
5 perc
ent
HC
1.
If
the
pape
r tu
rns
yello
w
aft
er
the
HC
1 w
ashi
ng,
the
entire
1
+ 2
Nfy
OH
, w
ate
r,
5 p
erc
en
t HC
1 cy
cle
is
re
peate
d
un
til
the
pape
r re
mai
ns
white
.
15.
With
th
e
pape
r a
cid
to
H
C1,
ad
d th
rou
gh
th
e
pape
r 2
15.
ml
of
2M citric
aci
d solu
tion.
Usi
ng
met
hyl
red
as
ind
ica
tor,
m
ake
the
filtra
te slig
htly a
cid
w
ith
1 +
1 H
C1.
R
eser
ve filter
pape
r.
Hea
t th
e filtra
te
on
the
stea
m b
ath
for
two
hour
s to
allo
w
the
Al
and
Fe
to
com
plex
.
16.
Add
a fe
w
drop
s o
f m
ethy
l re
d,
then
ad
d 1
+ 1
NH4O
H 16
. u
ntil
alk
alin
e
and
all
the
pre
cip
itate
ha
s dis
solv
ed.
17.
If,
whe
n th
e so
lutio
n
is
war
m
and
alk
alin
e,
it still
17
has
so
lid
ma
teria
l in
it,
filter
it
thro
ug
h
the
sa
me
No.
42
pa
per.
W
ash
well
with
5
pe
rce
nt
NH40
H an
d ig
nite
the
pape
r in
th
e
pla
tinum
cru
cib
le.
Fuse
an
y re
sidue w
ith
0.5
g N
32C
03,
extr
act
the m
elt
with
H
£0,
filte
r,
acid
ify w
ith
HC
1,
and
add
to
mai
n solu
tion.
Qu
an
tity
of
mol
ybda
te
so
lutio
n
giv
en
is
for
sam
ples
co
nta
inin
g
~ 50
perc
ent
P20
5-
Less
sh
ould
be
us
ed if
P205
co
nce
ntr
atio
n
is
expe
cted
to
be
le
ss do
wn
to
20 m
l fo
r 3
perc
ent
A ye
llow
p
recip
ita
te
of
amm
oniu
m
phos
phom
olyb
date
fo
rms
whi
ch
may
a
lso
co
nta
in
som
e w
hite
p
recip
ita
te
of
mo
lyb
dic
aci
d.
Yel
low
filtra
te
ind
ica
tes
inco
mp
lete
re
mov
al
of
silic
on
. Th
ese
occ
urr
ence
s ar
e u
nim
po
rta
nt.
All
the pre
cip
itate
w
ill
eve
ntu
ally
dis
solv
e
in
the
NH4O
H.
Citric
aci
d
is
adde
d to
co
mpl
ex
the
A
l an
d Fe
, w
hich
w
ill
occu
r o
nly
if th
e so
lutio
n
is
acid
ic.
Pho
spho
mol
ybda
te
may
re
pre
cip
ita
te
as
the
so
lutio
n
is
acid
ifie
d,
bu
t th
is
shou
ld
not
ala
rm
the analy
st.
Hea
t o
f th
e
stea
m
bath
en
cour
ages
th
e pre
cip
itate
to
dis
solv
e.
If
moly
bdic
a
cid
(w
hite
) ha
s pre
cip
itate
d,
a litt
le
mor
e tim
e
on
the
st
eam
bath
, w
ith
occ
asi
onal
stirr
ing,
will
be
nece
ssary
.
The
phos
phor
us
in
such
in
solu
ble
ph
osph
ates
as
th
ose
of
tita
niu
m
and
zirc
oniu
m is
co
nve
rted
into
so
dium
ph
osph
ate.
32
18.
19.
20,
21.
22.
23.
24.
25.
Adju
st
volu
me
of
the
so
lutio
n
to
200-
300
ml.
slightly a
cid
with
1 +
1 H
C1.
Ren
der
Add
10 m
l M
agne
sia
mix
ture
p
lus
0.1
ml
mor
e fo
r ev
ery
mg
of
?2^5
exp
ect
ed.
Stir
during a
dd
itio
n.
Whi
le stirr
ing,
mak
e th
e so
lutio
n
alk
alin
e w
ith
slow
dr
opw
ise
additi
on
of
1 +
1 NH
/jOH.
A
fter
the
pre
cip
itate
ha
s fo
rmed
, ad
d N
fyO
H to
10
perc
ent
of
tota
l sa
mpl
e vo
lum
e.
Stir
occa
sio
na
lly.
Let
stan
d overn
ight.
Filte
r th
roug
h a
12.5
cm
B
lue
Rib
bon
pape
r,
well
with
5
perc
ent
Was
h
Was
h th
e p
recip
ita
te w
ith
wa
ter
from
th
e pa
per
into
a
250
ml
beake
r.
Rep
lace
th
e
pape
r in
th
e
fun
ne
l w
ith
the
25
0 m
l be
aker
be
neat
h it.
Was
h th
e p
recip
ita
tio
n
beak
er w
ith
25
ml
1 +
1 H
C1,
th
en
pour
d
ire
ctly in
to
the
250
ml
beake
r.
Rin
se
the p
recip
ita
tio
n
beak
er
seve
ral
times
w
ith
ho
t 5
pe
rce
nt
HC
1,
po
urin
g th
e
rin
sin
gs
thro
ugh
the filte
r.
Was
h th
e
pape
r w
ell
with
hot
5 p
erc
en
t H
C1;
fin
ally w
ash
with
w
ater
tw
o tim
es.
D
isca
rd filter
pape
r.
Vol
ume
in
the
250
ml
beak
er
shou
ld
be
abou
t 10
0 m
l.
Add
a fe
w
drop
s of
met
hyl
red
, th
en
add
1-2
ml
Mag
nesi
a m
ixtu
re.
Stir
we
ll w
hile
m
akin
g alk
alin
e
as
be
fore
with
1
+1
NH
4OH.
S
tir
well
and
add
NH4O
H ve
ry sl
ow
ly during
the
pre
cip
itation.
Let.st
and fo
r an
ho
ur
or
mor
e w
ith
occ
asi
onal
stirr
ing
. Ad
d N
^OH
to
a
con
cen
tra
tion
o
f 5-
10
pe
rce
nt
as
be
fore
an
d le
t st
an
d ove
rnig
ht.
Filte
r th
roug
h 12
.5
cm
No.
42
pa
per
and
was
h w
el 1
with
5
pe
rce
nt
18.
19.
Evaporation
or dilution may
be ne
cess
ary.
So
luti
on
must be ac
id before addition of M
agnesia
mixture.
If sample is pu
re apatite, 50
ml
Magnesia mi
xtur
e wi
ll be
nee
ded.
23.
Prec
ipit
ate
shou
ld fo
rm v
ery
slowly a
nd b
e cr
ysta
llin
e.
If so
luti
on looks
murk
y an
d cloudy
duri
ng pr
ecip
itat
ion,
ad
d mo
re H
C1 to acidity, th
en
add
ammo
nia
agai
n.
33
26.
Pla
ce filter
in
a w
eigh
ed
pla
tinum
cru
cib
le.
Bur
n off
the
pape
r at
as
low
a
tem
pe
ratu
re
as
po
ssib
le
in
the m
uffle
. F
ina
lly,
whe
n ca
rbon
is
a
ll re
mov
ed,
ign
ite
at
1100
° to
M
g2p2
°7-
Coo
l in
desi
ccato
r an
d w
eigh
. R
epea
t ig
nitio
ns u
ntil
const
ant
we
igh
t is
obta
ined.
Ca
lcu
latio
ns:
Perc
ent
= w
t-
M92
P2°7
x
0-63
774
x 10
0 perc
ent
we
igh
t sa
mpl
eC
ompi
led
by
S.
Ne
il
34
REF
EREN
CES
Cru
ft,
E.
F.,
In
ga
me
lls,
C.
0.,
an
d M
uyss
on,
J.,
19
65,
Che
mic
al
analy
sis
and
the sto
ich
iom
etr
y o
f a
pa
tite
: G
eoch
emic
a et
Cos
moc
him
ica
Act
a,
v.
29,
p.
581-
597.
Hill
ebra
nd,
W.
F.,
Lundell,
G
. E.
F
.,
Brig
ht,
H.
A
.,
and
Hof
fman
, J.
I.
, 19
53,
Applie
d
Inorg
anic
A
na
lysis
, 2d
e
d.,
New
Yor
k,
John
W
iley
and
Son
s.
Hof
fman
, J.
I.,
and
Lu
nd
ell,
G
. E.
F
.,
1938
, A
na
lysi
s o
f ph
osph
ate
rock
: Jo
ur,
o
f R
esea
rch
of
the
N
atio
na
l B
urea
u o
f S
tandard
s,
v.
20,
p.
607-
626.
Kolthoff,
I.
M.,
Sandell,
E.
B
.,
Mee
han,
E.
J.,
an
d B
ruck
en
ste
in,
S.,
19
69,
Quantita
tive
chem
ical
a
na
lysis
: 4th
ed.,
To
ron
to,
The
Ma
cmill
an
C
o.-
Co
llie
r-M
acm
illa
n
Can
ada,
L
td.,
p.
642-
648,
p.
1127
-112
8.
Lundell,
G
. E.
F
.,
and
Hof
fman
, J.
I.,
1924
, Th
e analy
sis
of
phos
phat
e ro
ck:
J.
Ass
oc.
of
Off
. A
gri.
Che
mis
ts,
v.
8,
p.
184-
206.
Ma
xwe
ll,
J.
A.,
19
68,
Roc
k an
d M
inera
l A
naly
sis:
Ne
w Y
ork
, Jo
hn
Wile
y an
d S
ons.
35
MAIN
PO
RTIO
N ON PHOSPHATE
ROCKS
AND
MINERA
LS
(Procedure ad
apte
d fr
om E.
F. Cruft, C. 0. Ingamells, an
d J. Muysson, Geochimica et Cosmochimica A
cta, 19
65,
v. 29,
p. 581-597.)
Grav
imet
ric
analysis of rocks
and
mine
rals
co
ntai
ning
mor
e th
an
1 pe
rcen
t ?2®5
"*s
be
st ac
comp
lish
ed by
usi
ng
sepa
rate
portions each fo
r silica,
phosphorus,
and
the
remaining
main co
nsti
tuen
ts.
The
following
procedure
describes
the
separation an
d determination
of other
main
constituents af
ter
the
determination
of si
lica
an
d ph
osph
orus
. Th
e sa
mple
is fu
sed
with Na
2C03
an
d Na202, si
lica
is
re
move
d and
disc
arde
d, an
d ph
osph
orus
is
remo
ved
with
zi
rcon
yl ch
lori
de prior
to precipitation
of the
R203 gr
oup,
which
is la
ter
anal
yzed
by
che
mica
l me
thod
s.
Reagents (all chem
ical
s-re
agen
t gr
ade)
:
Zirc
onyl
ch
loride solution:
Weig
h an
d transfer 9-10 g
ZrOCl2*8H20
to a
500
ml vo
lume
tric
fl
ask.
Dilute to
volu
me wi
th H
20.
After
several
days
, filter the
solution in
to a
Pyrex
bottle fo
r st
orag
e.
Standardize
the
sollution
as fo
llow
s:
Remo
ve a
25
ml al
iquo
t and
precipitate
Zr(O
H)4
with
NH
40H
as in the
usua
l R203 gr
oup
sepa
rati
on.
Reprecipitate
afte
r di
ssol
utio
n in HC1.
Filt
er.
Place
filter an
d precipitate
in a weighed
Pt crucible,
char
th
e pa
per,
an
d ig
nite
to constant w
t at
1000°C.
Calculate
the
conc
entr
ation
of th
e solution in m
g/ml
Procedure
1. Determine
H20~ o
n a
1.0
g sa
mple
, th
en m
ix w
ith
it
0.2
g specpure q
uartz, 4
g Na
2C03
» an
d ap
prox
imat
ely
0.5
g Na202.
Fuse
in the
usua
l manner ov
er a
stro
ngly
oxidizing Meker
flam
e.
Cool.
2. Transfer th
e fusion to a
Pt di
sh with H2
0.
Add
abou
t 5
ml 1+
1 HC1
to th
e covered
dish co
ntai
ning
th
e fu
sion
. Le
t stand
over
nigh
t.
Add
the
HC1
from t
he
cruc
ible
, then carefully
wash an
d police it,
adding
the
wash
ings
to the
dish
. Carefully
wash th
e crucible
with
water, ig
nite
, cool an
d we
igh
it,
then
set
it
asid
e fo
r later
use.
3. He
at the
cove
red
dish on the
stea
m bath until
effe
rves
cenc
e ceases.
Then rinse
the
cover
and
side
s do
wn an
d remove an
d re
serv
e th
e cover.
4. Allow
to evaporate, UNCOVERED, to
dr
ynes
s.
Dehydrate
4. Fluoride m
ust
be entirely r
emov
ed,
as its
presence
overnight
on steam
bath.
interferes with
co
mple
te precipitation
of Al
. Removal
of F- is
more
thorough if di
sh is
completely
uncovered.
36
Comments
1. Quartz is ad
ded
to m
ake
the
volatilization of
fluoride
more c
omplete.
It is unnecessary
to ad
d it if
si
lica
content
of the
samp
le is
kn
own
to ex
ceed
5
perc
ent.
5. Re
move
dis
h fr
om s
team b
ath
and
allow
to co
ol.
Take
up the
salt
s in
10
ml
conc
entr
ated
HC
1.
Let
stand
10
minutes.
Wash down si
des
of d
ish
with 5
pe
rcen
t HC1
and
add
water
to a
total
volu
me o
f 50
-70
ml.
Heat
, covered, on
steam
bath until
salt
s are
dissolved
and
solution is
ho
t.
6. Filter th
roug
h 11
-cm
Black
Ribb
on paper, ca
tchi
ng
filtrate in a 60
0 ml
beaker.
Wash several
times
with
5 percent
HC1, th
en w
ith
hot
water
until
dilu
ted
meth
yl or
ange
sh
ows
that all
acid
ha
s been r
emoved.
7. When filter has
completely d
rained,
place
the
paper
in
the
rese
rved
cru
cibl
e an
d set
asid
e.
Retu
rn the
filtrate to
the
dish an
d de
hydr
ate
two
more
ti
mes
on
the
stea
m ba
th.
After
each d
ehydration,
take up
the
salts
in HC
1 as be
fore
and
during th
e fi
ltra
tion
of
the
sili
ca,
add
a pinch
of fi
lter
pulp.
Filt
er
thro
ugh
What
man
No.
40 o
r Mu
ntel
l's
00 p
aper.
Wash
thor
ough
ly as before.
8. Place
all
filters
in th
e Pt
cru
cibl
e, then burn t
hem
off
at a
low
temp
erat
ure
and
igni
te the
sili
ca.
No
need to weigh
the
silica.
9. Moisten
silica w
ith
a few
drops
of w
ater.
Add
3 dr
ops
HC10
4, 2
drops
HNOa
, and
half f
ill
the
cruc
ible
wi
th HF
. Ev
apor
ate
to fumes
on a
hot
plat
e.
Add
several
drop
s of w
ater
, pa
ck the
crucible h
alf
full of
pa
per
pulp
, an
d add
a few
ml NfyOH.
Place
in cold
muffle,
burn o
ff paper
at a
low
temperature, th
en
igni
te to re
d heat o
f muffle.
Cool
. Fu
se re
sidu
e wi
th 0.
5 g
Na2C03.
Diss
olve
fusion
in 10 m
l 1+
1 HC
1 and
add
to the
filt
rate
from t
he silica.
10.
Heat the
solu
tion
on the
hot
plate
to a
temperature
of
abou
t 90
°.
Volume of
the
solu
tion
should be
about
200
ml,
and
it should co
ntai
n ab
out
10 percent
HC1.
6. Diluted
meth
yl orange (~
0.00
5 pe
rcen
t) is
ap
plie
d dr
opwi
se to upper
edge of
fil
ter
after
it ha
s drained.
Pink
color
denotes
presence o
f ac
id;
if ac
id
has
been removed, the
indicator
will
be p
ale
yell
ow.
Samp
les
in wh
ich
phos
phor
us is
high c
reate
grea
ter
difficulty in complete removal
of HC
1 (d
ue to
fo
rmat
ion
of phosphoric acid).
8. Si
lica
is
me
rely
being re
move
d, not
determined.
9. Wh
ile
silica is
be
ing
igni
ted
and
vola
tili
zed,
heat
the
filtrates, covered, on the
steam
bath f
or se
vera
l hours
to convert
any
pyro
phos
phat
e present
to
orth
opho
spha
te.
37
11.
From t
he k
nown co
ncen
trat
ion
of P2
0s»
calculate
the
quantity o
f a
stan
dard
so
luti
on of
Zr
OCl2
which
must b
e ad
ded
to react
with th
e ?2^b
f Slowly a
dd
enou
gh of
th
e Zr
OCl2
fr
om a bu
rett
e to th
e ho
t so
luti
on to
th
eore
tica
lly
precipitat
e th
e ph
osph
orus
, pl
us an
excess of a
ppro
xima
tely
10
mg
11.
The
ratio
is Zr:2
P.
See
Hillebrand,
et al
, p.
56
9-67
1
12.
Plac
e the
beak
er on
the
steam
bath
an
d he
at it for
20-3
0 mi
nute
s, stirring o
ccas
iona
lly.
13.
Filter through
a 12
.5 cm
Whatman No
. 54
1 paper
folded
inside a
Blue
Ribbon paper, ca
tchi
ng f
iltrate
in a
1000
ml
beaker.
Wash the
prec
ipit
ate
supe
rfic
iall
y with 5
percent
HC1.
14.
Retu
rn th
e fi
ltrate to
th
e precipitation
beak
er,
using
as little w
ater as
po
ssib
le.
Add 20
ml co
ncen
trat
ed
HC1,
co
ver
the
beak
er,
and
heat on
the
steam
bath f
or
30 m
inutes to
an
ho
ur.
Add
water
to m
ake
a vo
lume
of
abou
t 200
ml.
15.
Filt
er again
thro
ugh
the
same
paper,
catching f
iltrate
in th
e sa
me b
eaker
as before.
Wash su
perf
icia
lly
with
5 percent
HC1
as be
fore
. Repeat st
eps
14 and
15 tw
o mo
re ti
mes.
16.
The
zirc
oniu
m ac
id p
hosphate (p
resu
med
to b
e of
the
comp
osit
ion ZrO^PO^) ma
y be placed in
a
larg
e Pt c
rucible, carefully
igni
ted
to Z^Oy,
and
anal
yzed
, if
de
sire
d.
For
specific in
stru
ctio
ns,
see
Cruft
et.
al,
p. 594.
17.
Evap
orat
e the
filtrate to a
volume o
f ab
out
250
ml in
400
or 6
00 m
l be
aker
.
14.
The
Zr ph
osph
ate
is an
ext
reme
ly b
ulky
pre
cipi
tate
, an
d it
would
be v
ery
difficult, if no
t impossible,
to
wash it
thoroughly in th
e fu
nnel
in the
usual
way.
16.
ZrOCl2+2H3P
04 >ZrO(H2P
04)2+2
HCl.
17.
If m
ore
Zr ph
osph
ate
prec
ipit
ates
du
ring
the
ev
apor
atio
n, it
may
be ig
nore
d.
38
18 19
Add
approximately
60 m
l NhtyOH.
Heat
so
luti
on to
boil
ing
and
prec
ipit
ate
the
R2®3 group
by a
ddition
of NltyOH to
pH 6
.4 as usual.
Filt
er through
an
11 cm
Whatman No
. 41
paper
fold
ed in
side
an
S.
and
S.
White
Ribb
on pa
per,
co
llec
ting
fil
trat
e in an
80
0 ml
beaker.
Wash thoroughly w
ith
hot
2 percent
NfyCl
as
usual
.
Tran
sfer
precipitate
back in
to the
prec
ipit
atio
n be
aker
an
d to
it
add
10 m
l HC1.
Heat until
prec
ipit
ate
dissolves, then re
prec
ipit
ate,
filter,
and
wash as
de
scri
bed
in "C
lass
ical
Analysis,
Main
Port
ion.
" Place
the
filt
er and
precipitate
in the
crucible in
which
the
orig
inal
fusion wa
s ma
de.
Burn
of
f th
e paper
at a
low
temp
erat
ure,
th
en ig
nite
at
1000°.
Weig
h.
20.
The
comb
ined
filtrates from t
he f
y®!
Q^oup
should
be e
vaporated
to approximately
300
ml
in a
600
ml
beak
er.
If th
e fi
ltra
te is no
t ac
id to
methyl red
following
the
evap
orat
ion,
add
1:1
HC1
drop
wise
to
the
red
color, then ad
d about
10 d
rops in ex
cess
.
21.
To the
boiling
filtrate,
add
40 m
l 10 p
ercent o
xali
c ac
id.
Remo
ve f
rom
the
burn
er and
place
the
beak
er o
n th
e st
eam
bath
. Add
NH40H
slowly,
drop
wise
with
stir
ring
until
prec
ipit
ate
star
ts to
fo
rm.
Then stir
occa
sion
ally
as
precipitate
is fo
rmin
g an
d settling t
o th
e bo
ttom
, adding N
H40H only a
s the
prec
ipit
ate
assu
mes
a heavy, crystalline
form.
22.
Fina
lly
add NH
^H until
the
meth
yl re
d has
turn
ed
yellow and
pH o
f th
e sample is sl
ight
ly h
ighe
r than 6.
23.
Dige
st th
e sa
mple
on
the
steam
bath fo
r 1-
2 hours,
stirring o
ccas
iona
lly.
Th
en re
move
fro
m heat and
let
stand
over
nigh
t.
18.
It is
un
nece
ssar
y to ad
d any
addi
tion
al Nf
yCl,
as
sample al
read
y co
ntai
n a
larg
e volume o
f HC1.
19.
The
weig
ht of the
mixe
d ox
ides
is m
eaningful
only t
o the
exte
nt that it is of
use
to the
analyst
in
dete
rmin
ing
the
quantity o
f K2
$2®7
to us
e ^n
a
first
step o
f th
e ex
tend
ed analysis of
the
^2®$
precipitate
(des
crib
ed at
the
end
of this section).
22.
The
pH m
ay b
e ch
ecke
d by d
ippi
ng a
small
piece
of
indicator
paper
into
th
e so
luti
on and
observing
the
color.
39
24.
Filt
er th
rough
11 cm
Wha
tman
No.
42 paper
into
a
1000
ml be
aker
. Wa
sh carefully
with 0.
1 pe
rcen
t
25 26
Using
water,
rinse
the
prec
ipit
ate
from
the p
aper ba
ck
into
th
e beaker in
which th
e precipitation
was
made
. Re
turn
th
e paper
to th
e fu
nnel
. Rinse
the
wall
s of
the
beaker w
ith
hot
5 pe
rcen
t (v
/v)
HC1
, ad
d 10 m
l 1:
1 HC
1, co
ver
the
beak
er,
and
heat on steam
bath un
til
the
precipitate
is dissolved.
Repl
ace
the
1000 m
l be
aker
un
der
the
funn
el wi
th a 400
ml be
aker
. When all
the
prec
ipit
ate
has
dissolved,
carefully
pour
the
liquid th
roug
h the
filter an
d collect
it in
the 4
00 m
l beaker.
Wash paper
thor
ough
ly w
ith
hot
5 percent
HC1,
th
en several
time
s wi
th wa
ter.
Reserve
the
pape
r.
27.
Adjust th
e volume o
f the
liquid to ~200 m
l an
d ad
d 3-
4 drops
of m
ethy
l re
d.
Bring
the
solution to
a
boil an
d ad
d Nl
fyOH
dropwise un
til
prec
ipit
ate
star
ts to
form
. Re
move beaker f
rom
burner and
place
on the
stea
m bath.
Add
NH/^
OH slowly,
dropwise,
with
stir
ring
as
in steps
21 an
d 22.
Omit
an
y further
addi
tion
of o
xali
c ac
id un
til
precipitation
is
complete,
then
ad
d 1
ml ox
alic
acid,
and
adjust to
pH 6
as
be
fore.
28.
Digest o
n steam
bath until
precipitate
has
settled
well
, then r
emov
e to
stand
before f
iltr
atio
n within
3-4
hour
s.
29.
Whil
e th
e calcium
prec
ipit
ate
is awaiting f
iltr
atio
n,
dissolve 7
g
(NH4)2HP04 in
a
smal
l am
ount
of
wate
r.
Pour th
e solution th
roug
h th
e No.
42 pa
per,
ca
tchi
ng it in
th
e beaker co
ntai
ning
the f
iltrate
from
the
firs
t calcium
precipitation.
30.
Filter t
he c
alci
um o
xala
te through
a new
No.
42 paper,
wash
well wi
th 0.
1 percent
ammo
nium
oxalate, 'a
nd
coll
ect
the
filtrate in th
e 1000 m
l be
aker
.
25.
Calc
ium
oxalate
does
no
t re
adil
y di
ssolve in ve
ry
dilute HC
1, therefore
1+1
HC1
must
be
us
ed fo
r dissolution
of the
majo
r pa
rt of
the
precipitate.
28.
The
seco
nd pr
ecipitate
of c
alci
um o
xala
te sh
ould
be
fi
lter
ed after
3-4
hours
as post-precipitation of
magnesium
will
oc
cur
afte
r lo
nger
standing.
40
31.
Tran
sfer
the
paper
to a we
ighe
d pl
atin
um crucible.
Ash
at a
low
temp
erat
ure,
th
en ignite to C
aC03
at
475-500°C.
Cool
. Ignite,
weig
h, an
d calculate
perc
ent
CaO.
32.
To the
filtrate from step 3
0, ad
d NfyOH
in the
amou
nt o
f 10 p
erce
nt of
it
s vo
lume
. Co
ver
and
let
stand
for
seve
ral
days
, stirring s
ever
al times
each
da
y.
33.
Filt
er M
gNH4
P04
through
an 11 cm B
lue
Ribbon
pape
r, wa
shin
g we
ll with 5
perc
ent
NfyO
H.
Dissolve
the
prec
ipit
ate
by w
ashi
ng w
ith
hot
5 pe
rcen
t HC1
and
catc
hing
the w
ashings
in a
150
or 250
ml be
aker
.
34.
Add
1.5-2
ml 15 percent
NH4C
1 for
ever
y 10
mg
MgO
that is ex
pect
ed.
Add
2-3
drop
s methyl re
d.
35.
Add
NlfyOH v
ery
slowly d
ropw
ise,
with stirring.
Do
not
strike the
walls
of th
e beaker w
ith
the
stirring
rod.
Co
ntin
ue th
e ad
diti
on of
tf
ie ammonia
until
the
methyl re
d has
turned y
ello
w and
precipitation
appe
ars
to b
e complete.
36.
Cover
and
let
stand
for
abou
t 30
min
utes
, st
irri
ng
occasionally.
Add
ammonia
in the
quantity o
f 10
pe
rcen
t of
th
e vo
lume
present.
37.
Let
stan
d fo
r an
hour
or m
ore, th
en ad
d 1
ml of
25
percent
(NH4
)HP04, stir and
cover
to stand
overnight.
31.
CaC03
should be
di
ssol
ved
in H
N03
and
checked
for
pres
ence
of
Mn as
in "Classical Analysis,
the
Main
Portion."
33.
If M
gO is k
nown
to
exceed
20 p
erce
nt (unlikely
inphosphate
samples),
the
second precipitation
should be
made in a
volu
me of 2
00 m
l or m
ore.
35.
Prec
ipit
ate
should form la
rge
crys
tals
. If
th
e liquid
takes
on a cloudy ap
pear
ance
, stop the
addition of
the
ammo
nia.
Ma
ke th
e solution ac
id again
with
HC
1 an
d begin
the
addition of NfyOH
again.
37.
Precipitation
is fa
cili
tate
d if,
each time th
e solution is stirred, the
walls
of t
he beaker are
wash
ed do
wn with 5
perc
ent N^
OH in su
ch a ma
nner
that a
thin
layer
of am
moni
a floats on to
p of
th
e solution.
41
38.
Filter th
rough
a No
. 42 W
hatm
an paper, combining
the
filtrate an
d washings with those
from t
he first
Mg
filtration.
Wash the
prec
ipit
ate
thor
ough
ly w
ith
5 pe
rcen
t Nf
yOH.
39.
Tran
sfer
the
filter to
a
pre-
weig
hed
plat
inum
cruc
ible
. Place
the
unco
vere
d crucible in a
cold,
well
-ventilated m
uffle
furnace.
Care
full
y char a
nd
burn o
ff th
e fi
lter
paper
at as lo
w a
temperature
as
poss
ible
, then ignite at
1100°C until
carb
on is
comp
lete
ly r
emov
ed.
40.
Cool
and
weigh
the V(
^2^1
' Repeat ig
niti
ons
40.
The
Mg2P
207
shou
ld be di
ssol
ved
in H2
S04
and
unti
l constant w
eight
is attained.
Correct
the
weig
ht
calc
ium
and
mang
anes
e de
term
ined
as
de
scri
bed
inby
su
btra
ctin
g the
Ca and
Mn pr
esen
t.
Then calculate
"Classical An
alys
is,
the
Main Po
rtio
n."
Compiled by
S.
Neil
42
REFERENCES
Cruft,
E. F.,
Inga
mell
s, C.
0.,
and
Muys
son,
J.,
1965,
The
stoi
chio
metr
y of apatite:
Geochimica et Co
smoc
himi
ca A
cta,
v. 29
, p.
58
1-59
7.
Millebrand,
W. I.,
Lund
ell,
G.E.F.,
Brig
ht,
H. A.,
Hoff
man,
J.
I.,
1953
, Ap
plie
d Inorganic
Analysis,
2nd
edit
ion,
John Wi
ley
and
Sons
, Inc.,
New
York
.
Kolthoff,
I. M.
, an
d Sa
ndel
l, E.
B.
, 19
52,
Text
book
of q
uant
itat
ive
inor
gani
c an
alys
is,
3rd
edit
ion,
Th
e Ma
cmil
lan
Co.,
New
York
.
43
EXTE
NDED
AN
ALYS
IS
OF
THE
AMM
ONI
A GR
OUP
PR
EC
IPIT
ATE
(A
dapt
ed
fro
m
an
unpublis
hed
met
hod
devi
sed b
y C.
0.
In
ga
me
lls)
In
rock
analy
sis
, it
is
cust
omar
y to
dete
rmin
e
alum
ina
by d
iffe
ren
ce
, by
subtr
acting t
he
weig
hts
o
f all
oth
er
amm
onia
gr
oup
constitu
ents
fr
om
the to
tal
we
igh
t of
the
am
mon
ia
gro
up
. T
hat
whi
ch
rem
ains
is
as
sum
ed
to
be
A12
03.
Occ
asi
onally
, ho
wev
er,
it
is
nece
ssary
to
do
an
exte
nded
analy
sis
of
the
R
^03
gro
up
, th
ere
by
dete
rmin
ing
alum
ina
dire
ctly b
y pre
cip
itation o
f al
umin
um
phos
phat
e.
This
ex
tend
ed
analy
sis
may
be
ne
cess
ary
whe
neve
r un
usua
l co
nst
ituents
or
co
ntam
inan
ts
are
expe
cted
to
ac
com
pany
th
e
R20
3 gr
oup,
su
ch
as
whe
n zi
rco
niu
m h
as
been
ad
ded
to
rem
ove
phos
phat
e.
Pro
cedu
re
1.
Add
to
the
amm
onia
pre
cip
itate
tw
enty
tim
es its
we
igh
t o
f po
tass
ium
pyro
sulfate
. H
eat
over
an
o
xid
izin
g
flam
e until
the e
ntire
pre
cip
itate
ap
pear
s to
hav
e d
isso
lve
d.
Set
th
e
cru
cib
le o
n a
porc
ela
in
pla
te
to
cool
.
2.
Add
to
the
fusi
on
10 m
l w
ate
r.
Whe
n th
e
fusi
on
cake
ha
s lo
osen
ed
from
th
e cru
cib
le,
tra
nsfe
r th
e cru
cib
le
con
ten
ts
to
a 25
0 m
l beake
r,
thoro
ughly
was
hing
an
d p
olic
ing
th
e cru
cib
le.
Add
10 m
l 1+
1
Hea
t be
aker
an
d its
con
ten
ts
on
the
stea
m b
ath
, e
vap
ora
ting
, if n
ece
ssa
ry,
to
a vo
lum
e of
~50
ml.
Whe
n th
e fu
sio
n
cake
ha
s dis
solv
ed,
filter
the
so
lutio
n
thro
ugh
a 9
on
Bla
ck
Rib
bon
pa
pe
r, co
llectin
g
filtra
te
in
a 25
0 m
l beake
r.
Was
h filter
care
fully
w
ith
1 perc
ent
4.
Pla
ce
the
filter
in
the
pla
tinu
m cru
cib
le
in
whi
ch
the
pyr
osu
lfate
fu
sion
was
m
ade.
B
urn
off
th
e pa
per
at
a lo
w
tem
pe
ratu
re
in
the m
uffle
fu
rnace
as
u
sua
l, th
en
ign
ite
a
t 80
0° .
5.
Whe
n th
e cru
cib
le
has
coole
d,
add
2 dr
ops
of
1+1
H2S
04
and
10
drop
s H
F.
Pla
ce
on
a cl
ean
hot
pla
te
and
heat
at
<100
°C
un
til
HF
is
rem
oved
, th
en
incr
ease
te
mp
era
ture
an
d heat
to
fum
es
of
S03
. Fu
se
the
resi
due w
ith
a litt
le
pyro
sulfate
, ta
ke
up
the
fusi
on
in
10
pe
rce
nt
H2$
04
and
add
to
the
mai
n so
lutio
n.
Com
men
t
1.
See
step
19,
Mai
n P
ort
ion
on
Pho
spha
te
Roc
ks
and
Min
era
ls.
44
6.
Wip
e off
the
cru
cib
le,
ignite,
and
wei
gh it.
cru
cib
le fo
r la
ter
use.
Res
erve
7.
Ad
just
th
e
volu
me
of
the
m
ain
solu
tion
to
~100
ml.
Add
to it
enou
gh o
f a
50
pe
rce
nt
NaOH
solu
tion
to
nearly,
bu
t not
quite,
ne
utr
aliz
e
the
fr
ee
aci
d.
8.
Hea
t al
mos
t to
boili
ng
(~80
°C)
and
rapid
ly
pour
it
into
a
larg
e
(250
-350
ml)
pla
tinu
m
dish
w
hich
co
nta
ins
enou
gh
NaOH
to
g
ive
a
final
conce
ntr
atio
n o
f 1
perc
ent
NaO
H.
Again
, heat
ne
arly t
o boili
ng,
then
d
ige
st o
n th
e
stea
m b
ath
for
an h
ou
r.
Let
stand u
ntil
coo
l.
9.
Filte
r in
to
a 80
0 m
l be
aker
th
roug
h a
Wha
tman
N
o.
541
pape
r fo
lded
insid
e
a B
lue
Rib
bon
pape
r.
Was
h th
e pre
cip
itate
with
a
so
lutio
n
whi
ch
is
1 p
erc
en
t in
Na
OH
and
in
10.
Rem
ove
the h
arde
ned
pape
r w
ithout
dis
turb
ing
the o
the
r an
d slu
ice
the
pre
cip
itate
fr
om it
back
in
to
the
larg
e
pla
tinu
m d
ish
. R
epla
ce
the
filter
in
the
fun
ne
l an
d w
ash
it
thoro
ughly
with
5 perc
ent
HC1
, ca
tchin
g
the
was
hing
s in
th
e origin
al
250
ml
beake
r.
11.
Add
5 m
l co
nce
ntr
ate
d
HC1
to
the
pre
cip
ita
te
tod
isso
lve
it,
he
atin
g if
nece
ssar
y.
Pou
r it
thro
ugh
the
filter,
in
to
the
250
ml
beake
r,
then
th
oro
ughly
w
ash
the
dis
h
and
filter
with
w
ate
r until
fre
e o
f aci
d,
12.
Nearly
neutr
aliz
e w
ith
a 50
p
erc
en
t solu
tion
of
NaO
H,
heat
to n
ear
bo
ilin
g,
then
po
ur it
into
en
ough
h
ot
20
perc
ent
NaOH
in
th
e
pla
tinum
di
sh
to
mak
e a
fin
al
NaOH
co
nce
ntr
atio
n o
f 3
to
5 p
erc
en
t.
13.
Cov
er
the
dish
a
t on
ce,
heat
to
b
oili
ng
, an
d boil
for
a m
inut
e or
tw
o.
Rem
ove
from
heat
and
let
stand
ove
rnig
ht
to
cool
th
oro
ughly
.
8.
Be
sure
to
ad
d th
e
sam
ple
solu
tion ra
pid
ly t
o
the
NaO
H,
as
a better
pre
cip
ita
te w
ill
result.
9.
The
pre
cip
itate
w
ill
consi
st of
hyd
roxi
des
of
iro
n,
tita
niu
m,
zirc
on
ium
, an
d th
e ra
re e
art
hs.
Th
e filtra
te
conta
ins
the
alum
inum
.
11.
The
analy
st
sho
uld
ke
ep
a re
cord
o
f th
e
volu
me
of
HC1
used
, so
th
at
the
amou
nt of
NaOH
ne
eded
in
th
e next
st
ep m
ay b
e e
asily
de
term
ine
d.
45
Filte
r th
roug
h th
e
sam
e pa
per
as
befo
re,
com
bini
ng th
e
filtra
te w
ith
the
firs
t filtra
te
conta
ined
in
the
800
ml
be
ake
r.
Was
h w
ith
cold
1
perc
ent
NaOH
co
nta
inin
g
0.1
pe
rce
nt
each
o
f N
a£C
03
and
NaC
l.
14.
15.
Pla
ce
the
filte
rs
in
the w
eigh
ed
pla
tinu
m cru
cib
le,
burn
th
e pa
pers
o
ff
in
the
muffle
fu
rnace
, an
d ig
nite
at
800°
.
16.
Mak
e th
e filtra
tes ju
st
aci
d
to
met
hyl
oran
ge w
ith
1+1
HC1
and
adju
st
the
volu
me
to
300-
350
ml.
Add
1-2
g of
diam
mon
ium
ph
osph
ate,
an
d th
en
1-2
ml
HC1
in
exc
ess
.
17.
Stir
in
a on
e cu
bic
in
ch
port
ion
of
filter
pulp
, heat
to boili
ng,
and
add
to
the
boili
ng so
lutio
n
10
g o
f am
mon
ium
ace
tate
d
isso
lve
d
in
a sm
all
amou
nt of
H20
. B
oil
for
3-4
m
inut
es
then
filter
while
ho
t th
roug
h an
11
cm
W
hatm
an
No.
40
pa
per.
W
ash
su
pe
rfic
ially w
ith
war
m 2
perc
ent
Nfy
Cl
solu
tion.
Do n
ot
let
the
pape
r ru
n co
mple
tely
d
ry
during
was
hing
an
d do
not
over
was
h.
18.
Slu
ice
th
e pre
cip
itate
ba
ck
into
th
e b
eake
r w
ithw
ate
r,
add
1-2
drop
s m
ethy
l or
ange
, th
en
1+1
HC1
drop
wis
e u
ntil
the so
lutio
n
is
aci
d
to
met
hyl
oran
ge.
19.
Dilu
te
to
abou
t th
e
sam
e vo
lum
e as
befo
re
and
add
0.5
g
diam
mon
ium
ph
osph
ate.
B
ring to
a
bo
il an
d ad
d 10
g
amm
oniu
m a
ceta
te
as b
efo
re.
20.
Bo
il fo
r 2
-3 m
inute
s,
then
filter
wh
ile h
ot
thro
ugh
the
sam
e filter
pape
r.
This
tim
e th
e pre
cip
itate
sh
ou
ld
be w
ashe
d w
ith
hot
5 p
erc
en
t N
fyl^
until
a port
ion of
the
filtra
te
give
s a
negativ
e
test
for
ch 1
or i
cle .
21.
Aft
er
the
filter
has
thoro
ughly
dra
ined,,
plac
e it
in
a pr
ewei
ghed
p
latin
um
cru
cib
le.
Slo
wly
bu
rn o
ff
the
pa
per
as
usu
al,
then
ig
nite
th
e p
recip
itate
to
co
nst
ant
we
igh
t a
t 10
00°C
an
d w
eigh
A
1P04
. C
alc
ula
te
perc
ent
15.
It
is
not
ne
cess
ary
to
w
eigh
th
e pre
cip
itate
, but
it
shou
ld b
e re
serv
ed
fo
r d
ete
rmin
atio
n
of
iro
n
and
tita
niu
m.
See
step 2
2.
20.
To
test
for
chlo
ride,
add
3-4
dr
ops
0.2N
Ag
NO^
to
a sm
all
test
tube.
Mix
with
se
vera
l dr
ops
of
filtra
te
from
th
e
fun
ne
l st
em.
If
ch
lorid
e
is
pre
sen
t,
a slig
ht
cloudin
ess
w
ill
occu
r in
th
e
test
tube
du
e to
fo
rma
tion
of
AgC
l.
46
22.
The
sodi
um hyd
roxi
de
pre
cip
ita
te
from
ste
p
15
conta
ins
iro
n,
tita
niu
m,
and
zirc
on
ium
oxi
des.
It
m
ay b
e fu
sed
with
tw
en
ty
times
its
we
igh
t o
f po
tass
ium
pyr
osu
lfate
an
d dis
solv
ed
as
in
ste
ps
1-5
.
23.
Adju
st
the v
olum
e of
the
so
lutio
n
to
~75
ml
in
a 10
0 m
l vo
lum
etr
ic fla
sk.
Det
erm
ine
tita
niu
m
co
lorim
etr
ica
lly b
y ad
ding
3-5
m
l 30
perc
ent
\\2®
2>
then
m
akin
g th
e
sam
ple
to v
olum
e.
Rea
d a
t 41
0 nm
, re
cove
ring all
the
solu
tion
for
rem
oval
of
pla
tinum
an
d d
ete
rmin
atio
n o
f to
tal
iron.
24.
Eva
pora
te
the solu
tion
in
a 25
0 m
l be
aker
to
fu
mes
of
$03
and
fum
e b
rie
fly to
d
est
roy
the
p
ero
xid
e.
Add
wat
er
to
abou
t 70
ml,
then
ad
d Zn
to
rem
ove
the
pla
tinum
as
dis
cuss
ed
in
"C
lass
ica
l A
naly
sis-
The
Mai
n P
ort
ion."
25.
Det
erm
ine
tota
l iron
by t
itra
tio
n
as
follo
ws:
Eva
pora
te
the
sam
ple
so
lutio
n
to
fum
es
of
$03,
th
en
incr
ea
se
the
heat
and
fum
e briefly
to r
id
the
sam
ple
of
any
org
anic
m
atter.
C
ool..
Ad
d w
ater
to
a
volu
me
of
70-8
0 m
l an
d tr
an
sfe
r th
e solu
tion
to
a 40
0 m
l beake
r.
Add
5 m
l co
nce
ntr
ate
d
HC1
and
a fe
w
gla
ss
boil
ing
bead
s.
26.
Hea
t th
e solu
tion
to b
oili
ng
, th
en
rem
ove
from
he
at.
Ad
d dr
opw
ise
the
S
nCl2
so
lutio
n
desc
ribed
in
com
men
t N
o.
25
un
til
the
so
lutio
n
turn
s fr
om
yello
w
to
co
lorle
ss,
then
ad
d only
1-2
dr
ops
mor
e.
27.
Coo
l th
e solu
tion
to r
oom
te
mpera
ture
(~
25
°C),
th
en
qu
ickly
add
10
ml
of
a 5
perc
ent
solu
tion
of
HgC
^.
Do
no
t a
llow
th
e
sam
ple
to
stand
lon
ge
r th
an
2-3
min
ute
s.
Add
enou
gh
wat
er
to
mak
e th
e
volu
me
~200
ml.
23.
A st
andard
so
lutio
n
of
tita
niu
m m
ay b
e pr
epar
ed
from
NB
S st
andard
sa
mpl
e no
. 15
4 as
d
ire
cte
d
by H
ille
bra
nd
, e
t a
l,
p.
582.
25T
ota
l iron
is
dete
rmin
ed b
y re
duci
ng all
the
iro
n
to
the
ferr
ou
s (+
2)
state
w
ith
stan
nous
chlo
ride,
then
titr
atin
g w
ith
0.1
N I^
Cro
Oy.
Th
e re
actio
n
is:
2Fe
+2 +
Sn
+4t=
*2F
e+3
+
Sn*
4.
Sta
nnou
s ch
loride
solu
tion
shou
ld b
e pr
epar
ed
fre
sh
by
dis
so
lvin
g
15
ml
SnC
l2
2
^0
in
10
0 m
l 1:
2 H
C1.
27.
Merc
uric
ch
lorid
e
is
adde
d to
o
xid
ize
an
y ex
cess
st
anno
us
ion
. Th
e re
act
ion
is:
2Hg~
*"2
+ Sn
+2 ^
^
Sn+4
+
2Hg+
l.
A silky w
hite
pre
cip
itate
w
ill
form
. 47
28.
Add
5 m
l co
nce
ntr
ate
d
^PC
fy
and
seve
ral
drop
s o
f di
phen
ylam
ine
sulfo
na
te
indic
ato
r an
d titr
ate
w
ith
0.10
0 N
K2C
r20y
to
a
purp
le
end
po
int.
C
alc
ula
te
perc
ent
tota
l Fe
as
m1K2
Cr2
07
x %
Cr2
07
x 79
"85
x 10
° =
Per
cent
Fe
20
wt.
sam
ple
in
mg
79.8
5 is
th
e m
illie
qu
iva
len
t w
eigh
t o
f Fe
203
expr
esse
d in
m
illig
ram
s.
REFERENCES
Hill
ebra
nd,
W. F.
, Lu
ndel
l, G.
E.F.
, Bright,
H. A.
, and
Hoffman, J.
I.,
1953,
Appl
ied
inorganic
anal
ysis
, Jo
hn Wi
ley
ana
Sons
, New
York
.
Kolthoff,
I. M.
, and
Sandell, E. B.,
1952
, Te
xtbo
ok of
qua
ntit
ativ
e in
orga
nic
anal
ysis
, Th
e Ma
cmil
lan
Company, Ne
w York
Sandell, E.
B.,
1959,
Colo
rime
tric
de
term
inat
ion
of traces of
met
als,
vo
l. Ill
of Chemical Analysis,
Interscience
Publishers,
New
York
.
Compiled b
y S. Neil
48
CLAS
SICA
L ANALYSIS:
THE
MAIN
PORTION
The
analy
sis
co
nsis
ts,
for
the
mos
t p
art
, in
th
e
separa
tion
and
mea
sure
men
t by
weig
hin
g o
f th
e
maj
or
oxi
de
s co
nta
ined
in
a silic
ate
ro
ck.
Thes
e co
nst
itu
en
ts
are
Si0
2,
A12
03,
Fe20
3,
FeO
, T
i02,
P2°
5»
Mn°>
M9
°>
Ca°>
N
a20,
l<
20,
and
tota
l H
20.
Pro
cedu
res
for
FeO
, N
a20,
l<
20,
and
tota
l H
20
are
se
t fo
rth
in
se
para
te
sect
ions.
The
an
aly
sis
be
gin
s w
ith
sam
ple
dry
ing
. Lo
ss
in
we
igh
t is
re
cord
ed
as
H20
~.
Aft
er
sodi
um
carb
onate
fu
sio
n,
silic
a
is
rem
oved
by
HC
1 d
eh
ydra
tion
an
d is
de
term
ined
by
vo
latiliza
tio
n w
ith
HF.
A
lum
inum
, ca
lciu
m,
and
mag
nesi
um
are
succ
ess
ive
ly p
recip
ita
ted
w
ith
amm
onia
, o
xa
late
, an
d ph
osph
ate;
an
d ig
nited
and
wei
ghed
as
oxi
de,
carb
onate
, an
d py
roph
osph
ate
resp
ective
ly.
Iro
n,
tita
niu
m,
and
phos
phat
e ar
e ea
ch
dete
rmin
ed
on
separa
te
port
ions.
Bec
ause
th
ey
are
foun
d in
th
e
amm
onia
gr
oup
pre
cip
itate
, th
ey
mus
t be
su
btr
act
ed
to
obta
in
A12
03
by d
iffe
ren
ce
. M
anga
nese
, w
hich
is
fo
und
in
the
filtra
te
from
th
e
amm
onia
gro
up,
may
be
separa
ted
there
from
with
p
ers
ulfa
te;
or
it
may
be
reco
vere
d la
ter
from
th
e
ignited
mag
nesi
um
and
calc
ium
p
recip
ita
tes.
In
ad
diti
on
to
th
e
afo
rem
entio
ned o
xid
es,
cert
ain
m
inor
co
nst
itue
nts
m
ay o
ccu
r in
so
me
rock
s.
In
the
ev
ent
of
the
ir
de
term
ina
tion
or
in th
eir
abse
nce,
an
a
cce
pta
ble
su
mm
atio
n sh
ould
lie
be
twee
n 99.8
an
d 10
0.3
pe
rce
nt.
W
hile
a
sum
mat
ion
so n
ea
r 10
0 perc
ent
does
no
t gu
aran
tee
a co
rre
ct
an
aly
sis
, an
unsatisfa
cto
ry h
igh
or
low
su
mm
atio
n is
d
efin
ite
p
roo
f of
err
or.
49
CLASSICAL
ANALYSIS:
THE
MAIN
PORTION
(Fro
m an unpublished
meth
od d
evis
ed by
C.
0. Ingamells)
Procedure
and
Fusing:
1.
Weigh
a 25-ml
plat
inum
cru
cibl
e an
d cover.
Add
to
the
cruc
ible
0.700
or 0.800
gram
of
thor
ough
ly m
ixed
samp
le.
2.
Heat
the
uncovered
crucible for
2 hours
in an ov
en at
105° *
5°C.
Place
covered
cruc
ible
in a
desi
ccat
or
for
30 m
inutes;
then
weigh
cove
red
cruc
ible
and
contents.
Repe
at th
e foregoing
until
constant weight
is attained.
3.
Plac
e th
e co
vere
d cr
ucib
le in a cold furnace; sl
owly
br
ing
the
temperature
to 4
50-5
00°C
, then re
move
th
e lid
and
heat fo
r a
further
30 m
inutes.
Comm
ents
See
sect
ion
on th
e ca
re an
d us
e of
pl
atin
um,
see
sect
ion
on the
mixing o
f sa
mple
s.
2.
Cons
tant
wei
ght
= ±
0.2
mg.
Also
Carbon,
orga
nic
matt
er,
or su
lfides attack platinum
duri
ng f
usio
n.
With sa
mple
s containing no sulfide,
litt
le wa
ter,
no
oxi
diza
ble
iron,
and
no carbonate
or
orga
nic
matter
, or if
th
e sa
mple
is
likely to fu
se or
sinter at the
low
temperature
used
, roasting m
ay b
e om
itte
d.
The
prel
imin
ary
heat
ing
is done w
ith
the
crucible cl
osed b
ecau
se s
ulfu
r, the
most
co
mmon
volatile,
is more completely r
emov
ed in
th
is way.
The
fina
l heating
with
th
e crucible o
pen
resu
lts
in
the
oxidation
of ir
on,
which
is mu
ch less likely to
cause
trou
ble
when it
is
in
the
ferr
ic c
ondi
tion
. Among
materials
whic
h ha
ve be
en ob
serv
ed to
vo
lati
lize
on the
cruc
ible
li
d, under
the
cond
itio
ns
described, ar
e me
tall
ic ch
lori
des,
ar
seni
c co
mpou
nds,
thallium c
ompounds (sometimes en
countered
in the
analysis of m
inerals
which
have
be
en separated
usin
g Clerici
solution), su
lfur
an
d selenium c
ompo
unds
, ammonium s
alts
, silica (if
fluo
ride
is pr
esen
t),
boron
comp
ound
s, an
d mercury.
50
4.
Plac
e the
cool cr
ucib
le o
n a
porc
elai
n pl
ate
and
mix
3 ou
t of
4 grams
anhydrous
sodium
car
bona
te w
ith
the
rock
powder
using
a small
platinum r
od.
Rotate th
e stirring r
od in
the
remaining
gram
of
Na£C03 an
d transfer t
he latter to
the
crucible covering th
e mi
xtur
e as evenly a
s po
ssib
le.
5.
Cove
r the
crucible an
d heat ve
ry s
lowly
over a Me
ker
burner,
gradually
increasing th
e oxidizing
flame
over
a period o
f ab
out
20 m
inutes until
the
mixture
begins
to s
inter.
Fina
lly
increase the
temp
erat
ure
to a
bright red
heat fo
r 5-10 m
inutes,
or until
insp
ecti
on
of the
fused
mass sh
ows
no r
eaction.
When th
e melt
is quiet, heat th
e to
p of th
e cr
ucib
le and
the
lid
for
a mi
nute
with
a separate o
xidizing f
lame to
melt
the
small
spatters of
flu
x on
the
lid
and
side
s.
Remove t
he lid, invert it
, and
lay
it o
n th
e porcelain
plate; pi
ck up th
e cr
ucib
le an
d swirl
or
tip
it so th
at th
e melt so
lidi
fies
in a cup
shaped
laye
r on
th
e walls.
Cover
the
crucible an
d cool on
th
e po
rcel
ain
plate.
Reheat br
iefl
y over a
Mek
er
burn
er until
the
bottom a
ppea
rs dull red-~30
seco
nds.
Cool on th
e porcelain
plate.
A.
If platinum d
ishe
s ar
e us
ed:
1.
Add
abou
t 5
ml of
water
to the
cruc
ible
co
ntai
ning
the
melt an
d allow
it to
stand
for
several
minu
tes.
St
ir gently
wit
h a
silica r
od to loosen the
melt
; transfer th
e contents of th
e cr
ucib
le as
completely
as possible
to a
300
ml platinum d
ish.
Sc
rub
the
cruc
ible
with
a po
lice
man
using
a total
of ab
out
30 m
l of water.
4.Th
eme
tals
.gram
should b
e free o
f Mg,
Ca,
and
heav
y If
much fe
rrou
s Fe or
Mn is suspected, ~0.1
should be ad
ded.
An oxidizing
flame
is ob
tain
ed by
rep
laci
ng t
he
platinum w
ith
a ni
ckel
crucible o
f th
e same si
ze.
If
the
red
hot
cruc
ible
is filmed with oxide, the
flam
e is su
ffic
entl
y ox
idiz
ing:
if a bright surface
appe
ars,
the
burner s
houl
d be
ad
just
ed for
more
ai
r.
An ox
idiz
ing
flame
must be
maintained
at all
time
s;
fail
ure
to do so
will
result in re
duct
ion
of ir
on an
d it
s de
posi
tion
in th
e pl
atin
um.
A.
If pl
atin
um d
ishe
s are
used:
1.
The
solu
tion
of
the
melt an
d th
e de
hydr
atio
n of
silica m
ay b
e accomplished ei
ther
in
pl
atin
um d
ishes
or in
250
ml porcelain
cass
erol
es.
The
use
of
plat
inum
with
samp
les
high in iron,
chromium,
or
mang
anes
e re
sult
s in the
introduction of
la
rge
amou
nts
of platinum;
+2
e.g.
Pt +
4 Fe
+ 6
4 Fe
The
use
of porcelain
resu
lts
in th
e in
trod
ucti
on of
about
0.1
perc
ent
Si02,
alth
ough
the
gain
may b
e counterbalanced
by t
he sm
all
loss
du
e to th
e tenacious
adhe
renc
e of silica to porcelain.
For
high
er ac
cura
cy,
plat
inum
is
recommended.
Sili
ca rods ar
e us
ed be
caus
e HC1
may
leac
h ca
lciu
m fr
om s
oft
glass.
51
2.
Add
5 ml of co
ncen
trat
ed h
ydrochloric
acid
to
th
e cr
ucib
le,
cover
it,
and
set
it on the
porcelain
plat
e.
Cover
the
dish
wit
h a
watch
glass.
If any
manganate
(evidenced by
a gr
een
color)
is present,
add
a few
drops
of e
than
ol.
Allo
w the
melt to
disintegrate overnight.
The
liquid volume sh
ould
not
be m
ore
than
about
60 m
l.
3.
Crush
the
resi
due
with th
e ro
d and
look
cl
osel
y fo
r gr
itty
particles
which
may
indicate incomplete
deco
mpos
itio
n.
With th
e dish covered, pipette
appr
oxim
atel
y 15 m
l of
concentrated HC1
through
the
spout.
When the
C02
has
evolved, ad
d th
e contents of the
crucible,
scrubbing
and
washing
it thoroughly.
Transfer the
cove
red
dish to th
e steam
bath until
bubbles
are
no
longer observed.
Wash
do
wn the
side
s of
the
dish
and
cover
glass
with
1:20 H
C1;
raise
the
cover
on a
silica gl
ass
triangle to pe
rmit
ev
apor
atio
n.
Stir at in
tervals
to pr
even
t th
e formation
of la
rge
NaCl cr
ystals.
As th
e re
sidu
e dries, carefully
crush
it to
a
powder wi
th th
e rod.
2.
Etha
nol
redu
ces
tetr
aval
ent
manganese
which
woul
d su
bseq
uent
ly r
eact w
ith
HC1
to form c
hlorine, wh
ich
in turn severely a
ttac
ks platinum.
3.
If un
atta
cked
mat
eria
l is
present, it
may b
e be
st to
star
t over,
perh
aps
regrinding the
samp
le to
pass a
finer
mesh,
or fu
sing
for a
long
er time.
Some
mi
nera
ls su
ch as
zircon,
chromite,
sill
iman
ite,
kyanite, ma
gnet
ite,
il
meni
te,
tourmaline,
beryl
diss
olve
with
diff
icul
ty in th
e me
lt.
(Dec
ompo
siti
on
Tech
niqu
es in Inorganic
Analysis by
Dolezal, Povondra
and
Sulcek,
p. 91
-103
7)
4.
Samp
les
which
cont
ain
fluorine sh
ould
no
t be
cov
ered
with glass.
5.
Sili
ca gl
ass
rod
ends
mu
st be
thoroughly r
ound
ed or
sili
ca chips
may
be ad
ded
to the
samp
le.
Tefl
on
cove
red
meta
l ro
ds may
be used if they p
rove to be
le
ak proof
after
soak
ing
for
sometime in concentrated
HC1.
52
B.
If p
orcelain ca
sser
oles
are
used:
1.
Remove m
elt
from
the
cr
ucib
le as
described
in A.
Iab
ove.
Add
the
5 ml
of c
once
ntra
ted
HC1
to the
crucible as
stated in
A.2
above.
2-
Immediately
add
15 m
l HC1
to the
casserole
asdescribed
in A.4.
Let
stand
for
seve
ral
hours
orovernight
and
then
add
the
conten
ts of
the
crucible.
3.
When
the
melt
has disintegrated, heat the
cove
red
cass
erol
e on
th
e steam
bath u
ntil 00
3 is
no longer
evolved.
Crush
the
soft
lu
mps
of h
ydro
us silica w
ith
the
rod,
raise
the
cover
on a
glass
triangle,
and
evaporate
as de
scri
bed
above, st
irri
ng f
requently.
4.
Examine
the
crucible cl
osel
y fo
r co
ntam
inat
ion.
Heat
it f
or se
vera
l hours
in a
furn
ace
at ab
out
800°C, or
over a
stro
ngly
oxi
dizi
ng f
lame
, an
d examine
it fo
r th
e pu
rple
stain
characteristic of iron.
If this
appe
ars,
add
hydrochloric ac
id to the
crucible and
heat
it
, co
vere
d, to d
issolve
the
iron
oxide st
ain.
Reserve
the
solu
tion
so
obt
aine
d for
addi
tion
to
th
e fi
ltra
te f
rom
the
sili
ca.
Repeat the
heat
ing
and
leac
hing
until
no m
ore
iron ca
n be
recovered.
B.
If porcelain
casseroles ar
e us
ed:
3.
Beca
use
dehydr
atio
n of
si
lica
is more d
ifficult in
porc
elai
n, it is particularly im
port
ant
to p
revent
the
form
atio
n of c
rusts
and
larg
e crystals of
sa
lt.
Because
porcelain
is chosen fo
r sa
mple
s high in iron,
exam
inat
ion
of t
he f
usion
cruc
ible
is m
ore
important.
53
Sili
ca Continue to heat the
plat
inum
dish
or porcelain
casserole
on th
e steam
bath un
til
the
odor
of
hydrogen ch
lori
de ca
n no
lo
nger
be detected after
cove
ring
th
e dish fo
r se
vera
l mi
nute
s an
d then
rais
ing
the
cove
r.
HC1
removal
may
take
se
vera
l ho
urs
and
may
be continued
overni
ght.
1.
2.
While
waiting
for
the
above, carefully
clea
n the
outs
ide
of th
e crucible,
ignite for
1/2
hour
at
1000°C,
cool
in a
desi
ccat
or,
and
weigh.
The
cruc
ible
should be
free
from
stain or discoloration
of an
y ki
nd an
d weigh
0.1
to 0.
3 milligram
less th
an
befo
re f
usio
n.
If th
e lo
ss is
large more th
an
1 or
2 milligrams the platinum in
trod
uced
in
to the
anal
ysis
must be re
move
d.
3.
Cool th
e platinum d
ish
or porcelain
crucible;
carefully
add
6-15
ml
of concentrated h
ydrochloric
acid
. Al
low
to st
and
for
10 m
inutes.
If ti
tani
um is
kn
own
to b
e lo
w, th
e sm
alle
r volume of
ac
id should be
used
. Wa
sh do
wn th
e cover
and
the
side
s of th
e dish
or casserole
with 1:20 h
ydrochloric
acid,
add
water
to a
volume of
50-70
ml,
and
heat
on
th
e steam
bath
with
stirring until
all
the
sodi
um chloride is
diss
olve
d 30
minutes if necessary.
Add
more w
ater
only if
ne
cessary.
Filt
er as
so
on as
possible
thro
ugh
a 9
or 11 cm
S
and
S black
ribb
on pa
per,
and
wash
wit
h cold 1:20 h
ydro
chlo
ric
acid,
scrubbing
the
dish an
d tran
sfer
ring
as
much as possible o
f th
e si
lica
to
th
e pa
per.
Fi
nall
y wash free of ac
id with
hot
wate
r.
The
progress of th
e washing
can
be
foll
owed
by
adding a
drop
of
very
di
lute
(0.005
perc
ent)
met
hyl
orange solution to
the
precipitate
in
the
paper
from
time
to ti
me.
As lo
ng as
it
shows
a pink color,
wa
shin
g sh
ould
be
co
ntinued.
2. 3.
See
Quantitative C
hemical
Analysis by K
olth
off,
Sa
ndel
l, Meeh
an,
Bruc
kens
tein
, 4t
h edition, pp
650-661, for
disc
ussi
on of si
lica
. Se
e al
so
Syst
emat
ic Analysis of Silicates
by Le
e C. Pe
ck,
Geological Su
rvey
Bulletin
1170,
pp 21
-26.
Filtration wi
ll be
slow,
recovery w
ill
be in
comp
lete
, an
d high va
lues
fo
r al
umin
a wi
ll re
sult
if
dehydration
isjncomplete.
The
temp
erat
ure
should
not
exce
ed 10
0° C
else
so
me of th
e si
lica
wil
l be
come
ps
eudo
-sol
uble
by
int
erac
tion
wi
th the
basi
c magnesium
chlo
ride
fo
rmed
in th
e dehydration.
The
clean
igni
ted
cruc
ible
will
be us
ed to ig
nite
Si02 and
the
R203
group.
Ti,
Fe and
Al form h
ydrolyzable
salts.
Ther
efor
e,
conc
entr
ated
HC1
is us
ed an
d is
di
lute
d after
a sh
ort
peri
od of
con
tact
. Fa
ilur
e to
was
h al
kali
sa
lts
out
of the
sili
ca re
sult
s in
th
e we
ighi
ng o
f chlorides
as
well
as silicates
and
the
conv
ersi
on to
su
lfat
es
duri
ng su
bseq
uent
tre
atme
nt.
The
erro
r in Si
0;?
is
negative;
in A1203, it
is
po
siti
ve.
Difficulties
in the
ignition of si
lica
to
constant w
eight
are
usua
lly
due
to incomplete w
ashi
ng.
54
4.
Rese
rve
the
filter co
ntai
ning
the si
lica
. Re
turn
the
4.
filtrate to th
e dish or casserole
and
evaporate
to
dryn
ess
as be
fore
, st
irri
ng to pr
even
t formation
of
larg
e crystals of
sodium c
hloride.
Dehydrate
overnight.
Fina
lly
take u
p the
resi
due
in 6-15 m
l of
concentrated h
ydro
chlo
ric,
le
t st
and
for
10 minutes,
add
wate
r, an
d wa
rm t
o complete solution of salt.
Add
a li
ttle
paper
pulp
to
th
e solution,
stir
thoroughly,
and
filter through
a Mu
nkte
ll 00 o
r Wh
atma
n No.
40 7
or 9
cm
paper.
Wash
th
orou
ghly
with
1:20
hyd
roch
lori
c acid,
scrubbing
the
dish or
casserole
very
carefully w
ith
the
aid
of sm
all
piec
es
of hardened f
ilter
pape
r; then w
ash
free
of ac
id w
ith
hot
wate
r, us
ing
meth
yl orange indicator
as be
fore
.
5.
Transfer th
e pa
pers
co
ntai
ning
the silica t
o the
same
5.
crucible th
at wa
s used for
fusi
on.
Burn
off
the
paper
at 20
0°C
and
igni
te th
e silica at 1050°C fo
r on
e hour.
Desiccate, cool,
weigh, an
d re
igni
te at 30
minute intervals
to constant we
ight
.
Cloudy f
iltrate
from
the si
lica
is du
e to
the
hydrolysis of
Ti.
If th
e washing
of th
e si
lica
is
skil
lful
ly d
one,
th
e vo
lume
of
the f
iltrate
will
not
much e
xceed
100
ml.,
ev
en after
the
intensive
washing
necessary
to remove all
hydrochloric acid.
Heat
ing
must begin
from
a cold o
ven
under
strongly
oxidizing
cond
itio
ns (an
open
window
at each end
of
the
oven).
Not
unti
l all
carb
on is gone sh
ould
th
e te
mper
atur
e be raised m
uch
abov
e 450
C.
Fail
ure
to
attain a constant w
eigh
t after
seve
ral
hour
s of
heating
is an indication th
at al
kali
es ar
e pr
esen
t an
d ar
e sl
owly
vol
atil
izin
g.
It is also po
ssib
le for
plat
inum
crucibles
to lose w
eight
on prolonged
heating
at high
te
mper
atur
es.
See
Quantitative
Chem
ical
An
alys
is by
Kol
thof
f, Sandell, Me
ehan
, Bruckenstein,
4th
edit
ion,
p.
45
6.
55
6.
When co
nsta
nt w
eight
has
been
attained,
add
enough
wate
r to
th
e cr
ucib
le to th
orou
ghly
moisten the
sili
ca;
1-10 d
rops of 1:
1 sulfuric ac
id (the greater
amount wh
en ti
tani
a is
high); an
d th
en 15 m
l of
hydrofluoric acid.
Place
the
cruc
ible
on
an aluminum
hot
plat
e se
t with a
surface
temp
erat
ure
slig
htly
ov
er 100°C
(too lo
w to cause
boiling
or spatter)
until
all
silica an
d excess hy
drof
luor
ic acid h
ave
been
removed.
Add
a few
drop
s of
wat
er,
pack
the
cruc
ible
1/
3 full of ashless
paper
pulp,
add
seve
ral
drop
s of
ammonium h
ydroxide,
and
burn o
ff th
e pa
per,
pr
efer
ably
by
putt
ing
the
crucible in a
cold m
uffle
furnace
and
slow
ly r
aisi
ng th
e te
mper
atur
e to 4
50°C
over several
hour
s.
Finally
igni
te strongly,
cool
in
the
desi
ccat
or,
and
weig
h.
6.
The
loss
in
weight during t
he h
ydrofluoric-sulfuric-
acid treatment
is co
unte
d as
si
lica
, bu
t it does not
represent
all
the
sili
ca in the
samp
le.
Desp
ite
the
doub
le de
hydr
atio
n wi
th h
ydro
chlo
ric
acid
, a
litt
le
always re
main
s in solution.
This is us
uall
y (b
ut no
t al
ways
) fo
und
almo
st e
ntirely
in th
e am
moni
a pr
ecip
itat
e, fr
om w
hich
it wi
ll be
recovered.
With
ro
cks,
it
is quite
permissible
to m
ake
an em
piri
cal
corr
ecti
on fo
r th
is un
reco
vere
d si
lica
, si
nce
it
inva
riab
ly am
ount
s to
about
0.10
to
0.20 p
ercent.
Whet
her
or no
t a
sili
ca recovery f
rom
the
ammo
nia
group
is worthwhile de
pend
s on th
e nature o
f th
e sample an
d th
e pu
rpos
e of th
e an
alys
is.
Such
a
recovery is le
ss m
eani
ngfu
l when porcelain
cass
erol
es
are
used
in
th
e si
lica
de
hydr
atio
n.
In m
iner
al
analysis,
espe
cial
ly w
hen
the
exac
t pe
rcen
tage
of
silica an
d al
umin
a is critical,
as it m
ay b
e in
cr
ysta
l structure
work
, si
lica
re
cove
ries
sh
ould
al
ways
be
made
from t
he a
mmon
ia gr
oup.
Th
e sa
me is
tr
ue in ro
ck analysis when th
e sa
mple
involved is to
be used as a
standard.
The
resi
due
remaining
afte
r hydrofluoric acid treatment
of th
e si
lica
will
be
left in the
crucible an
d we
ighe
d wi
th th
e am
moni
a group.
The
total
weig
ht o
f R203 w
ill
then
be
ob
tain
ed usin
g th
e em
pty
crucible w
eight
obtained
immmediately af
ter
the
fusi
on.
It w
ill
be as
sume
d th
at insufficient platinum w
as in
trod
uced
fr
om t
he
plat
inum
dis
h to c
ause
difficulty.
This
wi
ll be
true,
generally, fo
r si
mple
rocks
whic
h do
no
t co
ntai
n large
amou
nts
of Fe.
Fort
unat
ely,
in
terf
erin
g elements in th
e si
lica
determination
are
few.
The
chie
f ones ar
e fluorine,
tungsten,
moly
bden
um,
and
boron.
All
but
the
first
need
seldom
be c
onsi
dere
d in
ro
ck an
alys
is.
56
The
Ammo
nia
Group
1 3.
Prep
are
doub
le f
ilte
rs b
y folding
11 cm
Wha
tman
No.
41 paper
or S
and
S black
ribbon pa
per
(see co
mmen
t 6)
inside 11
cm
S
and
S No.
589
white
ribb
on paper.
Wash
th
e fi
lter
s wi
th a
little 2
perc
ent
solution whose
pH ha
s be
en adjusted to 6
.4.
In th
e filtrate from t
he silica,
put
a sm
all
square
of h
arde
ned
filt
er pa
per
unde
r the
end
of th
e st
irri
ng r
od to pr
even
t bu
mpin
g, so th
at a
slow
steady b
oil
can
be m
aintained.
Heat th
e filtrate,
which
should have a vo
lume
of
not
more th
an 200
ml,
and
usuall
y contains 5-20 m
l of hydrochloric acid.
Boil for
5-10 m
inutes or until
there
is no de
tect
able
od
or o
f HC1.
Add
a fe
w dr
ops
of br
omin
e water
if
high
iron samples
have be
en ev
apor
ated
in
platinum;
continue to
boil un
til
a drop o
f me
thyl
red
reta
ins
its
colo
r in solution fo
r at le
ast
3-5
minutes.
Cool
somewhat.
NH4C
1.Ad
d 50
ml
of 1
5 pe
rcen
t solution of
See
Syst
emat
ic Analysis of
Silicates
by L
ee C. Peck,
Geological Survey B
ulletin
1170,
pp 2
6-30,
for
a ge
nera
l di
scus
sion
of
th
e am
moni
a group.
Pre-
prep
arat
ion
of t
he f
ilter
pape
rs re
sult
s in
saturated
fibe
rs;
filt
rati
on wi
ll be fa
ster
. A
2 pe
rcen
t so
luti
on NlfyCl may
be p
repa
red
from 6
5 ml
of
th
e 15
perc
ent
solution di
lute
d to 500
ml.
The
pH
is checked
with th
e nitrazine
pape
r an
d adjusted w
ith
conc
entr
ated
ammonia.
Boil
ing
remo
ves
dissolved
oxyg
en,
C02^
an
d re
duce
s manganese
entirely t
o th
e di
vale
nt state.
Brom
ine
water
insu
res
the
comp
lete
re
oxid
atio
n of
ir
on
beca
use
the
reaction:
Pt +
4Fe"*"3
+ 6C
1- >
PtCl
6-2
+ 4Fe"*"2
occurs in plat
inum
. Manganese
will
be
oxidized
and
prec
ipit
ated
upon neutralization if
all
the
bromine
is not
driv
en off.
The
addition of
NI^Cl
is governed by
the am
ount
of
Mg expected.
To pr
even
t magnesium
precipitation
with
th
e ammonia
group, sa
mple
s co
ntai
ning
50
pe
rcen
t MgO
(dunite, periodotite) re
quir
e at
le
ast
15 gr
ams
of
ammo
nium
chlor
ide.
57
Add
pure
am
moni
a sl
owly
with
gent
le st
irri
ng u
ntil
4.iron just b
egins
to precipitate;
avoid
an excess.
Heat
th
e solution almost to
boil
ing
and
then ad
dam
moni
a dr
opwi
se w
ith
stirring un
til
a piece
ofnitrazine
paper
dropped
into the
solution as
sume
s a
gree
n color,
indicating a
pH c
lose to 6
.0.
Heat just
to b
oili
ng (o
ne r
oll
over
), check
the
pH b
y adding
anot
her
smal
l sq
uare
of
nitrazine
paper, ad
just
with
ammo
nia
if necessary, fi
nall
y br
ingi
ng p
H as close
to6.4
as possible.
Stir,
wash down the
side
s of t
hebe
aker
wit
h a
litt
le w
ater,
let
stand
for
not
more
than a mi
nute
, an
d filter.
Duri
ng th
e filtration,
keep
th
e papers from r
unni
ng
5.dr
y un
til
the
whole
of th
e solution ha
s be
en added.
Then
le
t th
e filter d
rain an
d wash w
ith
hot
2 pe
rcen
tam
moni
um c
hlor
ide
solution.
The
gelatinous mass
should be
br
oken
up b
y a
stream o
f liquid from th
ewash bo
ttle
beginning
at th
e to
p of
th
e co
ne an
dspiral ing
downward.
The
upper
edges
of t
he p
aper
shou
ld be washed wi
th particular
care.
About
100-
150
ml of
was
h solution ar
e normally u
sed.
There
is no
need to
transfer all
the
precipitate, bu
t th
ebe
aker
sh
ould be
rin
sed
three
or four times.
When
was
hing
is
complete,
and
the
filt
er ha
s dr
aine
d 6.
thor
ough
ly,
remo
ve th
e so
ft inner
pape
r co
ntai
ning
the
precip
itate, be
ing
care
ful
not
to di
stur
b th
eouter
paper
or br
eak
the
colu
mn of liquid in
the
funnel stem.
Spread th
e pa
per
with
th
e precipitate
on th
e in
ner
wall of
th
e pr
ecip
itat
ion
beak
er.
Wash
the
precipitate
from t
he pa
per
with a
jet
of water,
fold
th
e pa
per
and
rese
rve
it.
Pure ammonia
is prepared by
pas
sing
amm
onia
ga
s from
a cylinder in
to fr
eshl
y boiled wa
ter
cool
ed in
ic
e and
protected
from a
tmospheric C0
2*
pH m
ust
be kept be
low
6.5
to pr
even
t precipitation
of
Mn.
Nitrazine
paper
is used be
caus
e it fl
oats
an
d is
easier to
observe t
han
the
brow
n pr
ecip
itat
e-la
den
filtrate.
Ammonium c
hlor
ide
rather th
an am
monium n
itra
te is
used be
caus
e a
combination
of n
itra
te an
d chloride
makes
complete r
eduction of
Mn
almo
st im
poss
ible
. Al
so,
nitr
ate
prevents the
comp
lete
pr
ecip
itat
ion
of
Mn by
per
sulf
ate
late
r in
th
e sc
heme
.
In some instances
(see
co
mmen
t 8)
, a
thir
d am
moni
a pr
ecip
itat
e may
be contemplated,
in w
hich
ca
se th
e paper
is re
turn
ed to th
e filter fu
nnel
. Fo
r th
ree
prec
ipit
atio
ns it is
ad
vant
ageo
us to us
e S
and
S bl
ack
ribb
on pa
per
inst
ead
of W
hatm
an No.
41 fo
r gr
eate
r wet
stre
ngth
.
58
7.
Wash do
wn th
e si
des
of t
he b
eaker
with 1:20
hydrochloric ac
id,
add
5-10 m
l of
co
ncen
trat
ed acid
(mor
e if
man
gane
se m
inerals
are
invo
lved
), and
heat
to boiling.
Add
water
to a minimum
of 15
0-20
0 ml
; boil until
methyl red
is no longer decolorized
in th
e boiling
solution,
and
the
odor of
ch
lori
ne is
no
longer de
tect
ed.
8.
Prec
ipit
ate
with ammonia
as before
except
that t
he
rese
rved
No
. 41
or
the
black
ribb
on paper
shou
ld be
to
rn up
and
macerated
in th
e solu
tion
after
the
prel
imin
ary
neut
rali
zati
on o
f most o
f the
acid
and
before precipitation
is complete.
Heat ju
st to
boiling, wash do
wn the
side
s of
th
e beaker w
ith
water, ma
ke a
final
chec
k of
pH
with nitrazine
paper,
and
filter th
roug
h the
rese
rved
pa
per.
9.
Wash th
e pulp r
emai
ning
in
th
e be
aker
by
de
cant
atio
n,
using
hot
2 percent
ammo
nium
chloride
solution,
sque
ezin
g th
e pulp w
ith
the
stirring r
od,
and
pour
ing
the
washings th
roug
h the
filt
er.
Repe
at this two
or
three
times, then transfer everything to
th
e fi
lter
with th
e aid
of a
poli
cema
n.
Wash very c
aref
ully
, pa
rtic
ular
ly around the
top
edge
s of the
pape
r.
Churn
up t
he p
recipitate and
pulp w
ith
the
hot
wash
1iqu
id.
10.
Add
to the
beaker a
little
1 +
1 HC
1; wa
sh down th
e si
des
with ho
t 5
percent
HC1;
di
gest
for
a few
mome
nts;
add
a drop o
f methyl red
and
ammonia
to
neutralize.
Heat ag
ain.
Ad
d paper
pulp a
nd f
ilte
r th
roug
h a
sepa
rate
small
paper
into
the
filt
rate
.
7.
The
solu
tion
is boiled to re
move
oxidizing su
bsta
nces
8. 10.
Normally,
any
furt
her
addition of am
moni
um c
hloride
is not
necessary
in this second pr
ecip
itat
ion.
A
third
prec
ipit
atio
n of
the am
moni
a gr
oup
may
be
necessary
with
manganese m
inerals, samples
cont
aini
ng
large
amounts
of ir
on or
aluminum,
or w
hen
chro
mium
, ph
osph
ate,
ar
sena
te,
and
some o
ther unusual
constituents are
pres
ent.
With o
rdin
ary
rocks, two
careful
precipitations wi
ll leave
only n
egli
gibl
e amounts
of calcium, ma
gnes
ium,
manganese
and
the
alka
lies
in th
e pr
ecip
itat
e.
It is
im
poss
ible
to scrub
the
beak
er f
ree
of m
etal
hydroxides;
therefore
the
hot
HC1
step is
necessary. 59
11.
Finally
wash the
precipitate
thor
ough
ly t
o re
move
most o
f the
NfyCl, ma
king
the la
st w
ash
with
10-2
0 ml of
cold w
ater.
Do no
t di
stur
b the
prec
ipit
ate.
Drain
the
filt
er,
brea
k th
e co
lumn
of
liqu
id in
the
stem
, and
wash
of
f th
e end
of th
e funnel.
Cove
r th
e fu
nnel
co
ntai
ning
the
prec
ipit
ate
with a
piece
of filter pa
per,
th
roug
h which
moisture
may
esca
pe,
until
it
is dr
y enough to b
e co
nven
ient
ly
hand
led.
Place
on the
stea
m bath the
covered
filt
rate
which contains calcium, magnesium
and
mang
anes
e.
12.
Transfer th
e bu
lky
precipitate
to the
crucible
containing th
e residue
from t
he silica d
etermination
as fo
llow
s:
Tear an
11
cm
fil
ter
paper
in h
alf,
and
roll it
in
to a
cone
, with th
e po
int
at th
e center o
f the
torn
ed
ge.
Put
the
point
of th
e co
ne in
the
cruc
ible
, ma
king
a
sort
of funnel.
Turn
the
paper
containing th
e precipitate
upside
down,
and
fit
the
top
edge in
to the
improvised paper
funnel.
Usin
g an
othe
r piece
of fi
lter
pa
per,
pr
ess
the
mass do
wn
into
the
cruc
ible
. With pa
ir o
f blunt
Pt-t
ippe
d tweezers,
pack the
whole
into the
crucible,
pres
sing
it away f
rom
the
side
s as
much
as po
ssib
le.
Also ad
d the
small
paper
from s
tep
10.
13.
Place
the
crucible and
precipitate
in a
cold
muf
fle
furn
ace,
ra
ise
the
temp
erat
ure
slow
ly t
o ab
out
425°C,
and
leav
e at this te
mper
atur
e fo
r se
vera
l hours,
preferably o
vern
ight
. Then in
crea
se t
emperature to
abou
t 90
0 C.
, cool in a
desi
ccat
or,
and
weig
h.
Repeat th
e ig
niti
on to co
nsta
nt w
eigh
t, increasing
temperature
to as
high
as 1100°C if
al
umin
um is
hi
gh.
Samples
cont
aini
ng m
uch
iron
nee
d not
be
heated to
as
sign
a
temperature; they should be held
at ab
out
750°C
for
some
time before a
final
weig
hing
.
11.
The
fina
l wash w
ith
HgO
remo
ves
the
slight
possibility
that ir
on m
ay b
e lo
st as
a
vola
tile
ch
lori
de du
ring
the ignition of t
he o
xide
s.
The
filtrate is heated because
sometimes
more
R203 pr
ecip
itat
e appears
in the
form
of
a cloudiness o
r a
brown
precipitate.
The
solution must
be f
iltered
agai
n an
d th
e pr
ecip
itat
e added
to the
bulk
y R2
®3*
A white
gran
ular
pr
ecip
itat
e is
usually
CaC03.
12.
The
resi
due
in th
e crucible consists of
Ti
02,
Fe203, A1
203
and
P205
- Ho
weve
r, if
present
in th
e or
igin
al sa
mple
, co
lumb
ium,
ta
ntal
um,
prob
ably
tungsten,
unat
tack
ed chromite and
tourmaline,
bari
um s
ulfa
te,
and
zirconium
phos
phat
e may
also
be
present.
With the
use
of a
paper
cone
, even th
e bu
lkie
st of
am
moni
a pr
ecip
itat
es can
be contained
in a
25 ml
cruc
ible
without d
iffi
cult
y.
During ig
niti
on,
it
will
collect
into
a
single fl
uffy
mass
in th
e middle
of the
crucible,
with no
ne of th
e ox
ides
ad
heri
ng to
the
sides.
60
Reco
very
of
Si02 f
rom
the
Ammonia
Grou
p an
d Removal
of
Plat
inum
Due to C
rucible
Atta
ck.
1.
Add
to th
e mi
xed
oxides 20 t
imes their
weig
ht of
potassium
pyrosulfate, and
heat covered
over a
small
flame, gr
adua
lly
increasing temperature
after
20-3
0 mi
nute
s until
the
crucible b
ottom
is a
dull re
d.
Complete so
lution co
uld
take
an
hour an
d may
be
tested by le
ttin
g th
e un
cove
red
cruc
ible
cool in a
good
li
ght;
mass be
come
s transpar
ent
with cooling.
2.
When fu
sion
is complete,
cool on a
porcelain
plate,
and
add
to the
crucible ab
out
10 m
l of
wat
er.
Heat
on st
eam
bath for
5 mi
nute
s and
then tr
ansf
er
contents to
a
250
ml be
aker
, scrubbing
and
wash
ing
the
cruc
ible
th
orou
ghly
. Ignite and
weigh
the
cruc
ible
for u
se in ca
lcul
atin
g the
ammo
nia
group.
3.
Add
10 m
l 1:1
sulfuric acid and
digest on
steam
bath
un
til
all
solubles have d
isso
lved
. Tr
ansf
er beaker
to ho
t plate, un
cove
r, an
d ev
apor
ate
to fu
mes.
Continue heating
until
a wa
tch
glass
plac
ed o
ver
the
beak
er no longer sh
ows
cond
ensa
te.
4.
Cool
, ad
d 50
ml
1^0, st
ir,
heat im
medi
atel
y on th
e steam
bath to
dissolve a
ll bu
t the
fleecy S
i02»
Add
paper
pulp an
d filter immediately
through
a sm
all
fine paper
into
a
250
ml be
aker
. Tr
ansf
er ev
eryt
hing
to
th
e paper
and
wash carefully
with
1:
99
to a
volume o
f about
80 m
l.
1.
Fume
s of
SQ
% pe
rfor
m the
function o
f di
ssol
ving
the
oxid
es.
Therefore, to
o st
rong
hea
ting
wil
l re
sult
in
loss
of
most
of
the
excess $03
before a
ttack
is
comp
lete
. The
plat
inum
crucible
will
be attacked by
ther
efor
e the
platinum lo
st in the
and 1^
207
fusions
must
be
rem
oved
fr
om t
he d
issolved R203 gr
oup
and
weig
hed.
See
step 6
.
61
Burn off
the
paper
in the
igni
ted
and
weighed
5.crucible (s
tep
2),
ignite at
1000°C,
cool,
and
weigh.
Add
to t
he r
esidue a drop
of
sulf
uric
acid
and
several
ml of
hydrofluoric
acid;
evap
orat
e to
dryness.
Ignite the
crucible a
gain
, co
ol,
and
reweigh.
Fuse t
he r
esidue w
ith
one
gram p
otassium
pyro
sulf
ate,
di
ssol
ve m
elt
in a
few
ml H2
0, take up
with
10 p
erce
nt su
lfur
ic ac
id,
and
add
to th
e main
solu
tion
in
th
e be
aker
. Wi
pe o
ff th
e crucible,
ignite,
and
weigh.
Evap
orat
e th
e so
luti
on to 50 m
l.
Cool
, an
d ad
d to
6.th
e cold solution ju
st 3
gram
s of
gr
anul
ated
zi
nc.
Allow
to stand
unti
l reaction su
bsid
es.
Then
evap
orat
e to a
smal
l volume o
n the
steam
bath
, dilute
to ab
out
50 m
l, le
t stand
over
nigh
t, an
d filter of
fth
e pr
ecip
itat
ed p
lati
num.
Wash w
ith
1 percent
sulfuric ac
id,
ignite at
900°C, cool,
and
weig
h.
Add
a fe
w ml
HF to th
e cr
ucib
le,
evaporate
on a
hot
7.
plate, ignite a
t 900°-1000°C, co
ol,
and
weigh.
8.
Anal
yze
the
ammo
nia
grou
p for
Ti02
,P2
05,
and
A1203
on a
separate fusion.
The
LiB02~HN03 so
luti
on for
K an
d Na
is us
ed to
dete
rmin
e Fe
203,
Ti
02,
and
?2®5
colorimetrically.
A1203
may
be d
eter
mine
d by
di
ffer
ence
or
col
orim
etri
call
y from t
he sa
me so
luti
on
The
contents of
the
crucible
consist
of silicon
and
iron
. After
evap
orat
ion
with H2S04
and
HF,
only
the
Fe remains
and
is added
to the
diss
olve
d ammonia
grou
p.
Total
Si02
should include
the
Si02
just
reco
vere
d.
Washing
must
be
exc
epti
onal
ly t
horo
ugh,
as
re
mova
l of
th
e so
lubl
e me
tal
sulf
ates
is quite
diff
icul
t.
Often
granulated zinc contains traces of
Si02 w
hich
mu
st b
e driven o
ff to
obtain
the
exact
weig
ht o
f pl
atin
um r
emoved from the
cruc
ible
.
See
sepa
rate
pro
cedu
res
for
the
alkalies,
Ti02
, F6203, P205 an
d A1203.
62
Mang
anes
e
1.
Evap
orat
e in a
lite
r beaker th
e combined f
iltrates
from t
he ammonia
group
precipitat
e to ab
out
250-275
ml.
Heat to b
oiling after
transfer to a
400
ml be
aker
(preferably
the
same one
in w
hich the
ammo
nia
precipitation
was
conducted).
Put
a piece
of
hardened filter paper
under
the
end
of th
e st
irri
ng
rod.
Most
or
all
of t
he m
anganese w
ill
normally b
e fo
und
in th
e fi
ltra
te fr
om t
he ammonia
grou
p.
However,
both the
Ca a
nd M
g pr
ecip
itat
e mu
st b
e tested f
or Mn
Beryllium
and
the
rare e
arth e
leme
nts,
if
an
y, ar
e no
t pr
ecip
itat
ed at pH
6.4
. They a
re f
ound in the
ammonia
group
filtrate.
2. 3. 4.
To th
e bo
ilin
g so
luti
on,
add
drop
wise
a
fres
hly
prepared 25 percent
solu
tion
of
ammo
nium
per
sulf
ate
and,
al
tern
atel
y with it
, drops
of 1:
1 am
moni
um
hydr
oxid
e, in
su
ch a wa
y th
at th
e pH
of
the
solu
tion
re
main
s be
twee
n 5
and
7.
Acid
ity
of the
solu
tion
may
be
measured
by adding a
small
square o
f ni
traz
ine
paper
from
time
to t
ime,
an
d observing
the
color
it
assumes
on touching t
he so
luti
on.
Coll
ect
the
manganese
prec
ipit
ate
on an 1
1 cm
No. 40
paper
and
the
filtrate in an
80
0 ml
beaker.
Wash th
e precipitate
with 1
percent
ammonium sulfate.
Using
water
and
leaving
the
paper
in the
funn
el,
wash the
precipitate
from t
he paper
into
the
prec
ipit
atio
n be
aker
. Di
ssol
ve it b
y adding a mi
nimu
m of
3 pe
rcen
t su
lfur
ous
acid
.
Pour
the
solution th
roug
h the
filt
er,
coll
ecti
ng it
in a
150
ml beaker.
Wash th
e paper
thor
ough
ly w
ith
water.
Make su
re the
paper
is free from s
ulfite.
Rese
rve
the
pape
r to catch
the
second p
reci
pita
tion
.
Ammonium p
ersu
lfat
e de
comp
oses
in
the
boil
ing
solu
tion
with th
e production of f
ree
acid
. Ad
diti
on
of ammonia
is necessary
because
manganese
is reduced
in hydrochloric ac
id solution at
lo
wer
pH.
Abou
t a
half h
our
is required fo
r complete pr
ecip
itat
ion
of
manganese.
It ap
pear
s that trivalent
mang
anes
e is
first
form
ed,
and
this d
isproportionates in
to M
n (I
I)
and
Mn (I
V),
the
latter pr
ecip
itat
ing
as Mn
O(OH
>2.
If th
is
is indeed the
mechanism
of th
e reaction,
the
fact that it
proceeds slowly,
and
requires alternate
additions
of pe
rsul
fate
an
d ammonia
for
the
best
resu
lts,
is explained.
4.
The
filter paper
is re
used
be
caus
e tr
aces
of M
n an
d BaS04
may
be r
etained
on th
e pa
per.
63
5.
Put
a pi
ece
of h
ardened
paper
under
the
stirring r
od
and
bring
the
solution to
a
slow s
tead
y bo
il.
When
most of
the
sulf
ite
is gone,
add
seve
ral
drops
of 2
5 pe
rcen
t ammonium p
ersulfate, an
d boil until
prec
ipit
atio
n is su
bsta
ntia
lly
comp
lete
. Then slowly
add
ammonia
until
the
acid
is
ne
utra
lize
d.
Continue
boil
ing,
wi
th sm
all
alternate
addi
tion
s of
pe
rsul
fate
an
d ammonia, until
prec
ipit
atio
n is
co
mple
te.
Adju
st
pH t
o 6-7, and
filter.
Wash w
ith
ammonium sulfate.
6.
Evap
orat
e th
e co
mbin
ed filtrates
in an
800 m
l beaker
to a
volume of
ap
prox
imat
ely
400
ml.
Set
aside
for
Ca an
d Mg
.
7.
Return the
Mn precipitate
in it
s filter to
th
e precipitation
beaker.
Place
the
beaker in a
well-ventilated
muff
le furnace.
Slowly b
ring the
temp
erat
ure
to ab
out
500° to
as
h paper.
Cool
th
e be
aker
an
d treat
the
residue
with
20
ml
1 percent
H2S04
and
seve
ral
drops
of 1^
2.
Allow
to
stand
for
seve
ral
hours
at r
oom
temp
erat
ure
to permit
mang
anes
e to
dissolve.
Any
resi
due
is fi
lter
ed
thro
ugh
No.
42 paper
and
discarded
unless ba
rium
has
been requested.
In th
at event, pr
ocee
d with steps
8,
9, an
d 10
tot
al sulfur pr
oced
ure.
8.
Evap
orat
e th
e filtrate on
st
eam
bath to
near
dryness,
then heat on
hot
plate
till fumes
of 503
appear.
9.
Add
50 m
l H^
O, 10
ml
HN03 an
d 10
ml
1 pe
rcen
t periodic ac
id.
Cover
and
heat on
steam
bath
overnight
to de
velo
p the
pink
permanganate c
olor.
10.
Cool an
d transfer so
luti
on to 10
0 ml volumetric
flas
ks.
Dilu
te to m
ark
and
mix
well.
Prep
are
a series of
st
anda
rd Mn solutions
from e
ither
a 1000
ppm
solution or
from
a 20 p
pm so
luti
on wi
th'
predeveloped co
lor.
11.
Read th
e ab
sorb
ance
of s
ampl
es and
standards
at
545
nm.
Prepare
a calibration
curve
by t
he le
ast
squa
res
method.
Report un
know
ns as percent
MnO.
6.
The
evaporation
elim
inat
es ex
cess
NH3.
7.
A re
sidu
e, after
manganese
is dissolved, may
cont
ain
bari
um s
ulfa
te (a w
hite cr
ysta
llin
e pr
ecip
itat
e),
plat
inum
, an
d numerous oxides including
sili
ca.
Rare
earths,
if present, will di
ssol
ve w
ith
the
mang
anes
e.
In th
e re
sidu
e, additional tr
aces
of
man
y elements have b
een
found
spec
trog
raph
ical
ly including
bism
uth,
antimony,
lead,
bery
lliu
m, mo
lybd
enum
, iron,
aluminum,
copp
er an
d ni
ckel
. None o
f these
adve
rsel
y affect th
e total
anal
ysis
with the
exce
ptio
n of
be
ryll
ium
and
the
rare e
arth
s.
The
only e
lement
whic
h may
be almost co
mple
tely
rec
over
ed fr
om t
he
ignited
Mn pr
ecip
itat
e is
ba
rium
.
8.
Peroxide m
ust
be r
emoved as
it
interferes in th
e color
reac
tion
.
9.
2 Mn
++5
I04~
+>
2Mn0
4~ +
5~
+ 6H
.
10.
If a
colo
rles
s 1000 p
pm s
olution
is us
ed,
color
must
be d
evel
oped
with
nitr
ic acid and
periodate.
Calciu
m Place
a small
piec
e of h
arde
ned
filt
er paper
under
the
end
of th
e stirring r
od an
d br
ing
the
combined
filtrates
from
step
6 to
boiling.
Add
40 m
l of 10
perc
ent
(w/v
) ox
alic
ac
id.
Continue b
oiling w
hile
ad
ding
Nfy
OH sl
owly
until the
solu
tion
is al
kali
ne
to m
ethyl
orange.
Inte
rrup
t th
e addition o
f am
moni
a wh
ile
a precipitate
is forming.
Finally, add
2-3
ml
of am
moni
a in
ex
cess
, check
that the
pH is
6 or
slightly h
igher, an
d set
aside
to cool ov
erni
ght.
1.
2.
Using
No.
42 paper
and
a 1000 m
l beaker,
filter and
wash the
precipitate
with 0.1
perc
ent
ammo
nium
ox
alat
e so
luti
on.
3.
Rinse
the
precipitate
from
the
fil
ter
back
in
to t
he
precipitation
beaker with water
and
diss
olve
in
hot
5 pe
rcen
t HC
1.
3.
A new
batch
of o
xalic
acid
should stand
a da
y an
d then be
fil
tered
before us
e.
Boil
ing
insures
the
prec
ipit
atio
n of c
alcium o
xala
te
as the
mono
hydr
ate,
a
coar
se,
filt
erab
le pr
ecip
itat
e which
will
not
cree
p du
ring
fil
trat
ion
and
washing.
The
filtrate f
rom
the
ammo
nia
precipitate
may
be
trea
ted
in several
ways.
Mang
anes
e may
be r
emov
ed
with su
lfid
e or pe
rsul
fate
(d
escr
ibed
previously).
Nickel may
be r
emoved w
ith
dimethylglyoxime.
Resi
dual
rare e
arth
s or b
eryllium may b
e removed
by
addition of
more
ammo
nia.
Carbonate
may
be used to
separate co
mbined ca
lciu
m, strontium, an
d ba
rium
. Removal
of am
moni
um s
alts m
ay b
e de
sira
ble
in ce
rtai
n cases.
Ideally, however, only c
alcium,
remnants ot
ma
ngan
ese,
and
magnesium
are
present.
In this
procedure, th
e calcium
is separated
as oxalate
and
is
dete
rmin
ed as
ca
rbon
ate.
The
magnesium
and
mang
anes
e ar
e pr
ecip
itat
ed to
geth
er as am
moni
um p
hosp
hate
s,
ignited
to py
roph
osph
ates
, an
d weighed.
Mang
anes
e in
the
calc
ium
and
magnesium
precipitates is
determined
colo
rime
tric
ally
; re
sidu
al calcium
is re
move
d fr
om
the ma
gnes
ium
and
manganese
pyro
phos
phat
es,
and
determined.
Calcium
oxal
ate
does no
t dissolve r
eadi
ly in di
lute
hy
droc
hlor
ic ac
id.
Ther
efor
e, it is necessary
to
sluice it
from t
he p
aper and
wash th
e paper
three
or
four times
with
1:1
hydrochloric ac
id to
be sure al
l the
calcium
is di
ssol
ved.
65
4. 5. 6. 7.
Place
a 60
0 ml
be
aker
under the
funn
el an
d fi
lter
th
e hydrochloric ac
id so
luti
on th
roug
h the
paper
to
remove t
races
of p
latinum, silica,
etc.
Wash very
thoroughly w
ith
dilute h
ydrochloric
acid.
Wash fi
lter
paper
free of
ac
id us
ing
methyl orange
indicator.
Thro
ugh
the
wash
ed f
ilte
r paper
and
to the
filtrate
cont
aini
ng m
agne
sium
, add
7 gr
ams
dissolved
in a
small
volume o
f water.
Dilute the
HC1
solution so th
at it contains no
mor
e th
an 0.2
g of
Ca
O per
100
ml.
Care
full
y pr
ecip
itat
e from b
oiling solution as
before,
but
add
only ab
out
1 ml of 10 percent
oxalic ac
id when pr
ecip
itat
ion
is
subs
tant
iall
y co
mple
te.
Dige
st ho
t (o
n steam
bath
) for
an ho
ur.
Set
aside
to co
ol.
Afte
r four h
ours,
filter,
save
th
e fi
ltra
te,
and
tran
sfer
al
l th
e precipitate
to th
e pa
per.
Wash the
paper
and
prec
ipit
ate
as before.
Tran
sfer
to
a
smal
l pl
atin
um,
gold
, or po
rcel
ain
cruc
ible
which
has
been
heated to 475°C, cooled,
and
weighed.
Place
unco
vere
d in a
cold
muf
fle
furn
ace
and
bring
up to
475-500°C
gradually; th
en hold at
th
at te
mper
atur
e fo
r several
hour
s (o
vern
ight
).
Weigh
as CaC03.
Inspect
the
CaC0
3-
If it is pure w
hite
, no
Mn is
present.
If it is of
f-wh
ite
or brown, ma
ngan
ese
has
co-p
reci
pita
ted
with calcium, and
a co
rrec
tion
sh
ould
be
mad
e.
See
Reco
very
of
Mang
anes
e from C
alcium.
6.
Dibasic
ammonium p
hosp
hate
often
contains de
bris
.
In the
first
prec
ipit
atio
n, th
e la
rge
excess of
ox
alat
e an
d ammonium sa
lts
helps
to pr
even
t the
post
-pre
cipi
tati
on of m
agne
sium
, but
enou
gh of
the
latter ma
y still
remain to
cause e
rror if t
he second
prec
ipit
atio
n is permitted
to digest for
more than a
few
hours.
If bu
t little m
agnesium is pr
esen
t, th
e re
cove
ry o
f calcium
may
be rendered m
ore
comp
lete
by
longer standing.
If the
paper
is bu
rned
of
f to
o fast,
it is
likely
that some carbon m
ay r
emai
n unburned at 50
0°C.
A
furn
ace
which
permits
free ac
cess
of ai
r du
ring
ignition is needed.
Do n
ot exceed 500°C, ho
weve
r;
above
approximately
550°
C, CaC03
loses
C02-
Ignition to C
aO i
s no
t re
comm
ende
d.
CaO
avid
ly t
akes
up H20
and,
moreover,
slow
ly r
eacts
with C
02 in
the
atmo
sphe
re.
66
Mang
anes
e Recovery F
rom
Calc
ium
1.
Diss
olve
the
CaC
03 in dilute HN
Cb;
make
the
solu
tion
10
percent in HN
03.
Add
one
drop
H20
2 to
di
ssol
ve M
n (f
izze
s vi
olen
tly)
.
2.
Evap
orat
e the
solution to
near dr
ynes
s on th
e steam
bath to
destroy
H202
. Co
ol.
Wash do
wn si
des
of
beaker w
ith
wate
r.
3.
Add
approx.
0.1
g periodic acid o
r potassium
periodate, an
d heat near th
e boiling
poin
t (steam
bath
), fo
r se
vera
l hours
or lo
nger
if ne
cess
ary.
Co
ol.
4.
Make
to
vo
lume
. Compare
with standard so
luti
ons
by
read
ing
abso
rban
ce at
54
5 nm.
5.
Hand
le the
data
in the
usual
linear r
egre
ssio
nma
nner
. Adjust C
aC03 w
eigh
t by a
ssum
ing
the
Mn w
as
weig
hed
as Mn
203.
Calculate
the
reco
vere
d Mn
as
Mn
O.
Calculations:
mg jnf Mn
O (calculated
from t
he e
quation) x
vol.
in m
l=
mg Mn
O
Mn20
3 =
156.87
2MnO
70.94
=2.225 =
gr
avim
etri
c factor
mg M
nO x
2.225
= wt
. of M
n203
wt.
of C
aC03 -
wt.
of M
n203 =
corrected w
t. of
Pero
xide
mus
t be removed
as it interferes with th
e color
reaction.
Perm
anga
nate
color
development
may
even take se
vera
l da
ys.
4.
The
size of
the
vo
lume
tric
flask is ch
osen
on
the
basis
of t
he in
tens
ity
of c
olor w
hich
de
velo
ps.
67
Magn
esiu
m
1.
Comb
ine
the
filtrates
from t
he t
wo c
alci
um o
xala
te
prec
ipit
ates
an
d ma
ke th
e solution
10 p
erce
nt in
concentrated ammonia.
Allo
w to
stand
at le
ast
48
hours
(a w
eek
if Mg
is
low) with fr
eque
nt st
irri
ng,
striking t
he w
alls of
th
e be
aker
to in
itia
te
prec
ipit
atio
n.
2.
Filter th
roug
h a
larg
e (1
1 or
12.5 cm
) blue r
ibbo
n paper
and
wash superficially
with 5
percent
ammonia.
3.
Leav
ing
the
paper
in the
funnel,
diss
olve
the
prec
ipit
ate
in h
ot 5
perc
ent
hydr
ochl
oric
ac
id.
Rinse
the
lite
r beaker,
pour the
rinsings through
the
filt
er paper, an
d co
llec
t fi
ltra
te in a
250-ml be
aker
4.
Add
1.5
ml of
15
pe
rcen
t ammonium c
hloride
solu
tion
for
ever
y 10
mg
of Mg
O ex
pect
ed.
Dilute to 50
-100
ml
or to
200
ml if
more
than
ab
out
20 p
erce
nt Mg
O is
present.
Add
a little m
ethyl
red
indicator
and
then
ammo
nia
solution d
ropw
ise
just
to
the
neutral
color
of the
indicator.
5.
Add
ammo
nia
slowly w
ith
stir
ring
until precipitation
is su
bsta
ntia
lly
comp
lete
.
Make the
solution 10
per
cent
in co
ncen
trat
ed ammonia;
stir f
requently
for
an hour o
r mo
re;
then
ad
d 1
ml of
25 pe
rcen
t di
ammo
niur
p phosphate
solu
tion
.
Stir occasionally,
each time w
ashi
ng d
own
the
side
s of the
beak
er w
ith
5 pe
rcen
t am
monia
solu
tion
, and
leav
ing
a layer
of d
ilute
ammonia
on top
of t
he
solu
tion
. This ha
sten
s precipitation.
Let
stand
overnight.
See
Quantitative C
hemi
cal
Analysis by K
olthoff,
Sandell, Meehan,
Bruc
kens
tein
, pp
. 631-641, fo
r a
disc
ussi
on o
f ma
gnes
ium.
Larg
e fi
lter
paper
is used be
caus
e of t
he gr
eat
volu
me of so
luti
on.
Avoid
striking t
he w
alls of t
he b
eaker
with the
stir
ring
rod during t
his
precipitation.
If
precipitation
begins while
addi
ng a
mmonia,
pause
to
let
large
crys
tals
fo
rm.
A cl
oudy
fine
precipitate
is to be av
oide
d.
As li
ttle
as 1.50 p
erce
nt M
gO a
ppea
rs.
With high
magn
esiu
m, most can
be p
recipitated
with
out
maki
ng
the
solution strongly alkaline.
68
8. 9.
Before f
ilte
ring
, st
ir th
e solution se
vera
l ti
mes;
filter th
roug
h a
small
What
man
No.
42 paper
and
wash
thor
ough
ly w
ith
5 percent
ammonia
solu
tion
, tr
ansf
erri
ng all
the
precipitate
to the
paper.
Transfer paper
and
prec
ipit
ate
to a weighed
porc
elai
n or
platinum c
rucible
and
burn o
ff the
paper
at as
low
a temperature
as po
ssib
le 25
0°C.
Then ignite at
1100°C until
all
carbon is
re
move
d.
Weigh
as
After
weig
ht is
co
nsta
nt,
break
up the
pyrophosphate
in th
e crucible w
ith
a small, sh
arp
spat
ula
to b
e sure th
at no
carbonaceous
matt
er r
emai
ns.
If an
y black
mate
rial
is se
en,
the
ignition sh
ould
be
re
peat
ed,
at a hi
gher
temperatur
e if ne
cess
ary.
Magnesium
pyrophosphate
reta
ins
its
weig
ht u
p to
ab
out
1200 C
. At
higher temperatures,
loss of
is possible.
8.
Often
ther
e is some d
ifficulty
in removing al
l carbon
duri
ng t
he ignition.
Commonly a
small part o
f th
e py
roph
osph
ate
rema
ins
stubbornly b
lack,
even after
many h
ours ignition,
unle
ss the
conditions of
th
e ig
niti
on ar
e cl
osel
y co
ntro
lled
. Presumably,
carbon
becomes
graphitized
and
is protected
from
the air
by
the
prec
ipit
ate.
Th
is difficulty c
an b
e av
oide
d by
firs
t ch
arri
ng a
nd then bu
rnin
g of
f th
e pa
per
at as
Tow
a temperature
as po
ssib
le w
ith
a good ai
r su
pply
. The
use
of a well-ventilated
muffle is
essential, particularly if
platinum c
rucibles ar
e us
ed.
9.
A ca
refu
l in
vest
igat
ion
of the
cond
itio
ns necessary
to insure t
he w
eigh
ing
of stoichiometric
Mg2^
2^7
is discussed
by H
ille
bran
d, Lundell,
Brig
ht,
and
Hoff
man,
Ap
plie
d In
orga
nic
Analysis,
pp.
636-
639.
69
Calc
ium
Reco
very
From
Magnesium
1 2.
To the
crucible co
ntai
ning
the
igni
ted
and
weig
hed
pyrophosphates,
add
a little w
ater
an
d 1
ml of
1:1
sulfuric acid.
Warm g
entl
y an
d transfer the
cont
ents
of t
he c
rucible
to a
150
ml be
aker
, using
a po
lice
man
if n
ecessary.
Heat
on the
steam
bath un
til
solution is
complete,
adding m
ore
sulf
uric
ac
id if
ne
cess
ary,
up
to
a
total
of 5
ml (of
1:1)
for
1 g
of magnesium
pyrophosphate.
Fina
lly
add
wate
r to m
ake
the
solution 5
perc
ent
in
The
total
volume w
ill
usua
lly
be 2
5 ml
.
Cool
an
d ad
d as
nearly as po
ssib
le three
times
the
volu
me o
f ab
solu
te e
than
ol.
Allow
to stand
with
oc
casi
onal
stirring for
several
hour
s (o
vern
ight
) fo
r complete pr
ecip
itat
ion
of c
alcium s
ulfate.
Filter th
roug
h a
11 cm
Whatman No.
44 paper
and
wash
supe
rfic
iall
y wi
th 8
0 pe
rcen
t (v/v)
alco
hol.
The
beak
er an
d filter should be
kept
cove
red
as mu
ch as
possible during th
is filtration to pr
even
t evaporation
of a
lcoh
ol,
with resultant
solution of
the
calcium
sulf
ate.
Drain
the
filt
er an
d be
aker
thoroughly,
unco
ver
them
, and
let
stand
until
all
alco
hol
has
evap
orat
ed.
Diss
olve
the
CaS
04 b
y ad
ding
5 pe
rcen
t HC
1 to the
precipitation
beaker and
pouring
the
acid
through
the
filter paper
using
just enough so
luti
on to
dissolve
the
precipitate.
Add
1 ml
of 10
percent o
xalic
acid,
heat to boiling,
and
add
an excess of NfyOH.
Digest ho
t, co
ol,
let
stand
for
four
hours, fi
lter
th
roug
h No
. 42
paper, wash with 0.
1 percent
ammonium
oxalate, transfer to
a cr
ucib
le,
burn o
ff pa
per,
and
ignite to
Ca
C03
at 4
75°C.
2.
No m
ore
than
2.
5 ml
of 1
+1 ^04 m
ay b
e added
if
<1 g ma
gnes
ium
pyrophosphate
is pr
esen
t.
3.
EtOH m
ust
be b
etween 75 percent
and
80 p
ercent by
volume.
4.
The
alco
hol
wash
ing
solu
tion
sh
ould
be
made
fresh
with each u
sage.
One
hund
red
sixty
ml of e
thanol is
added
to 40
ml
wate
r in a
graduate.
6.
Catch
the
diss
olve
d Ca
S04
in a
150
ml be
aker
.
8.
The
filt
rate
fro
m this step is di
scar
ded.
70
9.
Cool an
d we
igh.
Subtract the
weight d
irectly
from
th
at of
the
magn
esiu
m pyrophosph
ate;
ad
d th
e we
ight
to corrected
wt.
of C
aC03 c
alcu
late
d in step 5
, Ma
ngan
ese
Recovery F
rom
Calc
ium.
Co
nver
t total
CaC03
to C
aO b
y multiplying
by 0
.560
2, th
e gr
avim
etri
c factor C
aO
.Ca
C03
9.
The
we
igh
t o
f C
a3(P
04)2
, th
e
form
as
it
exi
ste
d
in
the
mag
nesi
um pre
cip
itate
, e
qu
iva
len
t to
C
aC03
re
cove
red
is
al
mos
t equal.
CaC0
3
Con
vers
ion
Fa
cto
rs:
0.96
80Ca
3(P0
4)2
1.03
3F
71
Manganese
Recovery F
rom
Magnesium
1.
Evaporate
the
filt
rate
from th
e ca
lciu
m sulfate
on
the
steam
bath,
then he
at to
inci
pient
fumes
on a
hot
plate.
Test fo
r dryness
by p
laci
ng a
watch glass
over
th
e be
aker
for
a few
moments.
Ther
e sh
ould
be
no co
nden
sate
on
the
watc
h gl
ass.
2.
Dilu
te w
ith
a li
ttle
water an
d fi
lter in
to a
150-ml
beak
er.
3.
Make t
he solution 10
per
cent
in
ni
tric
acid,
add
about
0.1
gram o
f periodic acid or
potassium
periodate, an
d heat o
n the
steam
bath
un
til
oxidation
of m
anganese is
complete,
i.e. un
til
the
pink color
develops.
Cool .
4.
Dilute to
ex
actl
y 10
0 ml
or
mor
e if M
n is hi
gh.
Prep
are
a se
ries
of
dilute standards
from
a stock
solu
tion
of K
Mn04
- Me
asur
e the
abso
rban
ce o
f standards
and
unknowns at 54
5 nm.
Treat
the
data b
y th
e method of
le
ast
squares.
1.
Cl~
trac
es ar
e removed.
Calculate
the
manganese
foun
d to W\
2?2®
1 ancl
subtract it
s we
ight
from th
e weig
ht of
the
Mg2P
2^7
calc
ulat
ed in
step 9
, Ca
lciu
m Recovery
From
Mag
nesi
um.
Conv
ert
total
^2^2
^7 to MgO
by m
ultipl
ying
by
0.36
2, th
e gr
avim
etri
c fa
ctor
2M
gO
.
3.
Color
deve
lopment
has
been
known
to ta
ke a we
eken
d
5.
If m
anganese wa
s no
t de
term
ined
previously,
the
sum
of the
manganese
foun
d in
th
e ca
lciu
m carbonate
and
that found
in th
e magnesium
pyrophosphate
shou
ld co
me
very
close to
th
e to
tal
manganese
in the
samp
le.
If
it does not, it
is almost ce
rtai
n to ha
ve been
retained in
the
ammo
nia
precipitate; th
is o
ccur
s when
much phosphate
is pr
esen
t in the
samp
le,
when
iron is
very h
igh,
wh
en th
e am
moni
a gr
oup
is precipitated at
too
high a
pH,
and/
or un
der
cert
ain
othe
r conditions.
72
Exa
mpl
e of
Calc
ula
tions;
mg/
ml
MnO
(c
alc
ula
ted
fr
om
e
qu
atio
n)
x vo
l.
in
ml
= m
g M
nO.
Mn?
P?0
? 28
3.82
2TKT-
1407=
2.00
05 =
gravimetric fa
ctor
mg M
nO x
2.0005 =
mg MnP0
Beca
use
the
Mn in
the
Mg?P
?07
prec
ipit
ate
was
ignited
to M
n?P?
07, the
weig
ht
thereof
is su
btra
cted
di
rect
ly f
rom
the
weight o
f the
Mg2Pp0
7.
The
resu
lts
of th
e Main P
ortion
analysis ar
e reported in the
following
order;
Si02
, A1
203,
Fe
203,
FeO, Mg
O, Ca
O, Na
20,
K20, H20,
P205
, MnO.
Perc
enta
ges
should
be r
epor
ted
to tw
o decimal
plac
es.
Compiled b
y M. Cr
emer
73
CLA
SS
ICA
L A
NA
LYS
IS
INTE
RFE
REN
CES
IN
S
ILIC
A
DE
TER
MIN
ATI
ON
(Fro
m a
n unpublis
hed
pro
cedure
by
C
. 0.
In
gam
ells
)
The
mos
t co
mm
on
inte
rfere
nce
is fluorine,
whi
ch
in
a silic
a
dete
rmin
atio
n
caus
es
low
re
su
lts,
due
to
the
vo
latiliza
tio
n
of
fluoro
silic
ic
aci
d.
The
prob
lem
may
be
hand
led
in
seve
ral
way
s:
1.
A la
rge
exce
ss o
f al
umin
um ch
lorid
e
may
be
adde
d to
th
e HC
1 us
ed
to
dis
solv
e
the
sodi
um
carb
onate
fu
sio
n.
Alu
min
um
com
plex
es
fluorine
and
pre
vents
th
e
loss
o
f silic
a
by v
ola
tilization.
2.
Bo
ric
aci
d
may
be
adde
d b
efo
re
the
HC1
additio
n
to
drive
off
BF3
.3.
Th
e sa
mpl
e m
ay
be
heat
ed w
ith
pe
rch
loric
and
bo
ric
aci
d.
Bo
ric
aci
d
is vola
tilized
from
p
erc
hlo
ric
aci
d,
whi
ch
rem
oves
th
e flu
orin
e
as
BF3
.
Pro
cedu
re
For
N
umbe
r 1
1.
Det
erm
ine
mo
istu
re,
om
it ro
astin
g,
and
fuse
0.6
to
1
.0 g
ram
of
sam
ple
in
the
usua
l w
ay.
2.
Leac
h w
ith
H20
in
a
pla
tinu
m
dis
h
in
the
usua
l m
anne
r.
3.
Whe
n m
elt
has
com
ple
tely
d
isin
teg
rate
d,
acid
ify
by
addi
ng
50
ml
of
10
perc
ent
(w/v
) A
lCla
-GI^
O
in
1:3
H
C1.
4.
Deh
ydra
te silic
a
as
usu
al;
how
ever
, m
ake
a th
ird
dehyd
ratio
n
to
insu
re
com
plet
e ca
ptu
re o
f silic
a.
Dis
card
th
e filtra
te
unle
ss
the
sa
mpl
e co
nta
ins
rare
eart
hs
whe
n th
e filtra
te
may
be
us
ed
to
dete
rmin
e
them
.
The
analy
sis
is
con
tinu
ed
on
a
no
the
r port
ion
of
the
sa
mpl
e by
re
mov
ing
the silic
a
in
the
usua
l m
anne
r,
i.e
. w
ith
ou
t th
e a
dd
itio
n
of
A1C
13-6
H20
.
Comments
The
large
amount of a
lumi
num
decr
ease
s the
effi
cien
cy
of t
he d
ehydration process.
Normal re
cove
ry o
f si
lica
from the
ammonia
group
is not
feas
ible
.
The
sili
ca is discarded
and
the
anal
ysis
is co
ntin
ued
by p
reci
pita
ting
the am
moni
a group
from
the
filtrate.
74
Procedure
For
Numb
er 2
The
following
procedure
is ap
plie
d to
to
urma
line
, a
boro
n-be
arin
g mi
nera
l, wh
ich
also
co
ntai
ns
appreciable
fluorine.
1.
Fuse th
e sample in the
usual
way
with
leac
h in pl
atin
um w
ith ^0
, an
d add
10 m
l of
5
perc
ent
boric
acid
be
fore
HC1
addition.
2.
Evaporate
uncovered
to dr
ynes
s on
th
e steam
bath
.
3.
Cool
. Add
alte
rnat
ely
2 to
3 m
l of
co
ncen
trat
ed HC
1 and
2 to 3
ml
of m
ethanol, cooling
the
dish
be
fore
each ad
diti
on an
d evaporating
to dr
ynes
s afterwards,
alwa
ys with th
e dish uncovered.
Do no
t ov
erhe
at.
Loss
by
spl
atte
ring
can oc
cur.
4.
After
seve
ral
trea
tmen
ts with al
coho
l an
d ac
id,
cont
inue
with
the
silica d
etermination an
d am
moni
a gr
oup
prec
ipit
atio
n as
usual.
5.
Igni
te th
e am
moni
a precipitate
in silica o
r Vy
cor
crucibles, separate f
rom
the
R203
re
sidu
e le
ft
from
the silica de
term
inat
ion.
6.
When the
ammonia
grou
p pr
ecip
itat
e reaches
constant
weight,
mix
the
oxides th
orou
ghly
with
a pl
atin
um r
od
or sp
atul
a.
7.
Weigh
appr
oxim
atel
y 10
mg
of t
he p
recipitate in
a
gold crucible.
Add
a pellet o
f so
dium
hydroxide and
heat just to
fus
ion.
8.
Cool
. Add
H20
and
leac
h.
9.
Evaporate
to 0
.1 ml
an
d proceed
with the
determination
of b
oron b
y th
e cu
rcum
in m
etho
d of
Haye
s and
Metcalfe.
1.Boron
accompanies
sili
ca an
d is volatilized
by t
he H
F treatment
causing
high results
for
sili
con.
Th
eref
ore,
it m
ust
be r
emoved b
y ev
apor
atio
n.
See
comm
ents
2
and
3.
2. 3.B(OCH3
)3
5.Boron
removal
is often
not
complete,
so the
ammo
nia
group
must
be
examined for
traces.
9.
Anal
yst,
Vol. 88
, pp._471-476, (J
une
1963
).
75
Procedure
For
Numb
er 3
The
following
procedure
is applied
to fluorite w
here
fluo
rine
is pa
rt o
f the
chemical formula.
1.
Prep
are
a bo
ric-
perc
hlor
ic ac
id solution saturated
with
H3
B03
by a
ddin
g an
ex
cess
of
^803 to a
mixture
of 2
5 ml HCltfy an
d 70 m
l ^0 a
nd he
atin
g with st
irri
ng to
80*C.
2.
Weig
h 0.500
g of
the
sample into
a
400-ml pyrex
beak
er an
d ad
d 15
ml
of th
e ho
t acid.
3.
On a
hot
plat
e, digest uncovered
below
the
boiling
point
unti
l most of
the
H20
is expelled.
4.
Gradually
increase th
e heat unti
l th
e pe
rchl
oric
ac
id
fumes.
Continue he
atin
g for
five m
inut
es after
stro
ng fu
mes
are
evolved.
5.
Cool
, wa
sh do
wn the
side
s of
the b
eake
r with H2
0,
and
repe
at th
e ev
apor
atio
n an
d fu
ming
.
6.
Dilu
te the
residue
with 50-75
ml of
^0
, heat to
boil
ing,
an
d fi
lter
.
7.
Wash
wi
th 1:
20 HC1
and
H20
as usual; tr
ansf
er all
insolubles to th
e fi
lter
.
8.
Tran
sfer
th
e filter to a
plat
inum
crucible, add
2 drops
concentrated HoSO/i (to
decompose
any
CaF2
); pack half fu
ll of as
hles
s paper
pulp,
add
seve
ral
drop
s of ammonia, an
d bu
rn off
the
paper
at
as lo
w a
temp
erat
ure
as possible.
9.
Ignite strongly,
cool
, weigh
and
rehe
at,
if
necessary,
to
co
nsta
nt w
eigh
t.
10.
Determine
Si02
as
us
ual;
i.
e. by
vol
atil
izat
ion
with
HF.
76
11.
Continue th
e an
alys
is with th
e pr
ecip
itat
ion
of t
he
ammonia
group, et
c. as
usual.
Howe
ver,
if
the
group
is large, it
should be
examined fo
r boron
contamination see
steps
6-9, Procedure
for
No.
2 Classical
Anal
ysis
-Int
erfe
renc
es in Silica
Dete
rmin
atio
n.
Comp
iled
by M
. Cremer 77
CLA
SS
ICA
L A
NA
LYS
IS
INC
OM
PLET
E A
TTA
CK
O
F SA
MPL
E
(Fro
m
an
un
pu
blis
he
d
proc
edur
e by
C
. 0.
In
gam
ells
)
Som
e m
inera
ls
whi
ch re
sis
t N
a?03
a
tta
ck
are
chro
mite
, kya
nite
, m
agnetit
e,
ilme
nite
, to
urm
alin
e,
be
ryl,
zirco
n,
and
sillim
anite.
A g
ritt
y re
sid
ue
d
urin
g fu
sio
n-le
ach
ing
with
H
£0
or
aci
d
indic
ate
s
that
the
analy
sis
sho
uld
be
sta
rte
d
agai
n w
ith
a m
ore
fin
ely
gr
ound
sa
mpl
e an
d/or
a
lon
ge
r or
hotter
fusi
on
or
a st
ronger
oxid
ant.
Sod
ium
p
ero
xid
e
in
pla
tinum
may
be
us
ed.
1. 2. 3. 4. 5. 6.
Pro
cedu
re
Tar
e on
a
pla
tform
ba
lanc
e th
e cru
cib
le
conta
inin
g
the
sa
mpl
e;
quic
kly
ad
d 3-4
gr
ams
of
Naz
O?
and
mix
w
ith
a pla
tinum
or
silic
a ro
d.
Wei
gh
1 gr
am
Na£
C03
on
w
eig
hin
g
pape
r an
d cl
eanse
th
e
rod
by
rota
ting it
in
the
carb
onate
.
Sp
rin
kle
th
e cru
cib
le.
Cov
er
hour.
over
th
e
conte
nts
of
the
an
d he
at
in
a 50
0°C
m
uff
le
for
one
Cool,
plac
e th
e cru
cib
le
in
the
dis
h
or
cass
ero
le
whi
ch
is
to
be
used
fo
r th
e silic
a
de
term
ina
tion
, co
ver,
an
d ad
d 50
ml
of
War
m
ca
utio
usly
if
so
lutio
n
is
slow
.
Whe
n th
e
solu
tion
beco
mes
q
uie
sce
nt,
acid
ify w
ith
HC1
to lim
it
the
attack
on
th
e
vess
el
by t
he h
ot
alk
ali,
pro
cee
din
g
as
in
a N
a£C
03 fu
sio
n s
ee
Cla
ssic
al
Analy
sis-
Main
P
ort
ion
.
1.
Com
men
ts
is
hyg
rosc
opic
an
d a
pow
erf
ul
oxid
izin
g
flu
x
to
be
used
w
hen
Na£
C03
is
in
eff
ective
. A
lso,
ore
m
inera
ls
of
met
als
such
as
C
u,
Pb,
A
g,
As,
etc
. m
ight
allo
y w
ith
the
pla
tinum
d
urin
g
a fu
sio
n.
3.
Tem
pera
ture
m
ust
be care
fully
co
ntr
olle
d
beca
use
abov
e 50
0°C
N&
2®2
att
ack
s p
latin
um
rapid
ly e
ven
mor
e se
vere
ly if
muc
h Mn
or
C
r ar
e pre
sent.
The
fusi
on
can
neve
r be
do
ne
by
flam
e.
Onc
e solu
tion
be
gin
s, it
proc
eeds
ra
pid
ly w
ith
bo
ilin
g
and
evolu
tion
of
oxyg
en.
Com
pile
d by
M.
Cre
mer
78
TOTAL
SULF
UR
Sulf
ur is determined gr
avim
etri
call
y as BaS04.
Most of th
e sulfur o
ccur
s as su
lfid
e in
th
e form o
f py
rite
or
pyrrhoti
te (F
e7S3
).
Sulf
ur-b
eari
ng silicates
are
more ra
re;
smal
l am
ount
s of su
lfat
es m
ay b
e pr
esen
t in th
e fo
rm o
f barite,
celestite, gy
psum
, al
unit
e.
Elemental
sulfur or organic
compounds
containing su
lfur
ar
e un
usua
l,
that
all
sulf
ur-b
eari
ng portions are
attacked an
d oxidized,
the
sample is
fused
in an
alkali flux.
The
melt
is
leached, filtered,
and
the
filt
rate
is rendered ac
idic
. Ba
rium
chl
orid
e is added
to th
e fi
ltra
te;
the
resulting
prec
ipit
ate
is ig
nite
d an
d we
ighe
d as BaS04.
Cr c
an be
de
term
ined
colorimetrically on
th
e fi
ltra
te be
fore
ac
idif
icat
ion.
Th
e re
sidu
e from
the
filtrate contains ba
rium
, nickel,
zircon
ium,
hafnium, an
d th
e rare ea
rths
.
Procedure
Comments
So
1. Weigh
0.5
g sa
mple
in a
Zr crucible.
Mix
well
3.
5 g
N320
2 an
d sprinkle a
small
amou
nt of
ov
er t
he m
ixture.
with
With a
Tirr
ill
burn
er,
begin
to gently h
eat
the
crucible.
Then gradually
heat
the
cruc
ible
to b
otto
m re
dnes
s while
swir
ling
no
w an
d then to
check
for
undecomposed lu
mps.
The
inner
core
of the
flame
shou
ld fo
rm a
bu
tton
on
th
e bo
ttom
of
the
crucible.
1. Th
e sa
mple
shou
ld no
t be ground to
o fine o
r th
ere
is
danger of
oxidizing
sulf
ide
to sulfur dioxide.
N32C03 sl
ows
down th
e ra
pid
oxidation
proc
ess.
Zr crucibles
are
used be
caus
e N3202
atta
ck on
Pt
is severe at temperatures gr
eate
r then
450-500°C.
In addition,
if mu
ch su
lfur
is pr
esen
t,
platinous
sulf
ide
forms
on th
e crucible.
2. Na
^Op
send
s fo
rth
smal
l ho
t grains if he
ated
to
o quickly.
If m
uch
orga
nic
material is
pr
esen
t, th
e mi
xtur
e may
even
ca
tch
fire
wit
h attendant
loss of
sa
mple
. In addition,
care
mus
t be
ta
ken
to ex
clud
e flame
gases.
The
comb
usti
on products of ga
s co
ntai
n ox
ides
of
sulf
ur avidly t
aken
up b
y alkaline f
luxe
s an
d solutions.
79
3. When th
e fusion is co
mple
te,
cool th
e cr
ucib
lesomewhat and
place
it in
a
150
ml be
aker
co
vere
d with
a watch
glass.
Cautiously add, a
little at
a
time,
appr
ox.
25 m
l ^0.
Place
on st
eam
bath until
reac
tion
is
qu
iet.
Remove t
he crucible,
rins
ing
it
well with H
20 and
policing t
he in
teri
or.
The
volume
in th
e beaker is approx.
less than 50 m
l.
4. Re
turn
beaker t
o steam
bath w
here it
should remain fo
r ap
prox
imat
ely
an ho
ur.
Remove from s
team b
ath
and
let
stand
overnight.
Next
morning,
filter th
roug
h no.
42
filter paper
within which
is folded 4
1H paper.
Use
a 400
ml beaker.
Wash w
ell
with 1
percent
NaOH
. If
other
elements ar
e to
be
de
term
ined
, qu
anti
tati
vely
transfer the
residue
to th
e paper
and
set
it aside.
Add
a few
drops
of m
ethy
l re
d to th
e filtrate.
5. Calculate
the
amount of 1+
1 HC
1 necessary
to re
nder
the
filt
rate
just
acid an
d pr
ovid
e a
1-2
perc
ent
exce
ss.
Add
the
entire amount o
f ac
id at o
nce.
The
tota
l vo
lume
in
th
e be
aker
will be
ab
out
200
ml.
Place
a small
piece
of 41H
filt
er paper
under
the
stir
ring
rod
in th
e beaker.
6. Begin
heat
ing
the
filt
rate
with
a small
Tirrill
burn
er
flam
e.
When it
is
bo
ilin
g ge
ntly
, ad
d dr
opwi
se
thro
ugh
the
cent
er hole in th
e watchglass ap
prox
. 15
ml of
10 p
erce
nt
BaCl2
solu
tion
. Pause
in the
addi
tion
of
the BaCl2
while
precipitation
is
occurring.
If th
e methyl re
d de
comp
oses
, ad
d more to
be
sure solution is
ac
id.
7. Digest on t
he steam
bath
. Re
move
an
d let
stand
overnight.
Stir
oc
casi
onal
ly.
3. Alternatively, h^O ma
y be ad
ded
to th
e co
vere
acr
ucib
le w
hile
it
is
ho
t.
The
reaction is
usually
so
swif
t th
at the
cruc
ible
mus
t be
pl
aced
qu
ickl
y in co
ld
H20
to quench th
e reaction an
d avoid
overflow.
4. The
filt
rate
contains sulfur and
chromium.
The
resi
due
cont
ains
ba
rium
, zirconium, an
d nickel.
5.
If HC
1 is
ad
ded
drop
wise
, Si wi
ll precipitate
in great
quan
titi
es re
nder
ing
the
filt
rati
on of
BaS04
impo
ssib
le.
Filter paper
beneath
the
stir
ring
rod
prevents bu
mpin
g as the
solu
tion
boils.
6. Do
no
t boil too
long.
Si will precipitate.
80
8. Filter through
no.
42 paper
contained
with
in a
41H
pape
r.
Wash
thoroughly w
ith
cold H?
0, us
ing
very
smal
l po
rtio
ns,
as BaStty is sparingly
soluble
in
H20.
9. Burn of
f paper
and
ignite to
consta
nt we
ight
at
ab
out
700°C
in a we
ighe
d Pt crucible.
10.
To the
cruc
ible
containing t
he BaSC
^, ad
d a
drop o
f H2S04
plus
a
few
drops
of HF
. Ev
apor
ate
to
dryn
ess
on a
hot
plate.
Reignite and
reweigh.
8. BaS04
is solu
ble
to th
e extent o
f 2.
4 mg
/lit
er at
20°C.
It is so
lubl
e to th
e extent of 6 mg
/100
ml
in
3 percent
HC1.
9. Th
e pr
ecip
itat
e is
easily r
educ
ed to su
lfid
e by
carbon
formed in
filter paper
char
ring
. Th
eref
ore,
paper
should b
e ch
arre
d very slowly at
low
temperature
with
free access of
ai
r.
10.
Some
silica m
ay h
ave
sepa
rate
d with the
8380
4.
After
HF t
reatment,
one
igni
tion
of th
e BaS04
is
suff
icie
nt.
For
a discussion on th
e me
thod
s of
reporting
sulfur,
see
reference
1, pp
. 235-236.
Compiled by
M.
Crem
er
81
CONVERSION FA
CTOR
S
so2
^
°'50
0^ s
so
3 M
8S»
s so
4 c
-333
8>s
1.9981
2.49
71
2.9959
7.28
07
3.64
38
2.9156
2.42
99
82
REFERENCES
Kolthoff,
I. M.
, Sandell, E. B.,
Meeh
an,
E. J.
, Br
ucke
nste
in,
Stanley, 1969,
Quantitative Ch
emic
al Analysis,
4th
ed
New
York,
Macmillan
Co., p.
602-617.
Maxwell, John A.
, 1968,
Rock an
d Mi
nera
l Analysis:
New
York
, Interscience P
ublish
ers,
p.
234-243.
Scot
t, Wi
lfre
d W.
, 1939,
Stan
dard
Met
hods
of
Chemical Analysis,
5th
ed.:
New
York
, D.
Va
n No
stra
nd Co
., Inc.,
p. 90
3-94
1.
83
SULF
UR
TRIO
XID
E
(Quo
ted
verb
atim
fr
om
Sys
tem
atic
A
na
lysi
s o
f S
ilicate
s,
p.
82,
Geolo
gic
al
Sur
vey
Bu
lletin
11
70,
by
Lee
C.
Pec
k)
Wat
er
is
adde
d to
a
1.00
00-g
ram
port
ion
of
the
sa
mpl
e.
The
wat
er
is
bo
iled
, an
d a
fte
r hydro
chlo
ric
aci
d is
ad
ded,
boili
ng
is
contin
ued
for
an
ad
ditio
na
l 15
m
inute
s.
The
solu
tion
is filte
red
, an
d th
e filtra
te
is
neutr
aliz
ed w
ith
amm
oniu
m h
ydro
xide
and
then
re
acid
ifie
d w
ith
hydro
chlo
ric acid
. S
ulfa
te
ion
s ar
e pre
cip
itate
d
by t
he additi
on
of
bariu
m chlo
ride.
The
solu
tion
is filte
red
, an
d th
e pa
per
con
tain
ing
th
e pre
cip
itate
is
bu
rned
o
ff
in
a w
eigh
ed
pla
tinu
m cru
cib
le.
The
cru
cib
le
and
its
conte
nts
ar
e ig
nite
d
and
wei
ghed
.
Su
lfid
e su
lfu
r is
de
term
ined
by
diffe
rence a
fte
r se
pa
rate
dete
rmin
atio
ns
for
tota
l su
lfu
r an
d fo
r sulfur
trio
xid
e.
Pro
cedu
re
1.
Tra
nsf
er
a 1.
0000
-gra
m
port
ion of
the
sa
mpl
e in
to
a 25
0-m
l E
rlenm
eyer
flask.
Pla
ce
a sp
ray
tra
p
(fig
. 6)
in
th
e
neck
o
f th
e fla
sk.
Add
80 m
l o
f w
ate
r,
and
bring it
to
a gentle
b
oil
over
a
Tirrill
bu
rne
r.
Bo
il th
e w
ate
r fo
r 1
min
ute
; th
en
add
20 m
l o
f 1
-to
-l
hydro
chlo
ric
aci
d
thro
ugh
the
fun
ne
l,
slow
ly
enou
gh
so
that
the so
lutio
n
does
not
sto
p
boili
ng.
Con
tinue
boili
ng g
en
tly fo
r 15
m
inute
s.
2.
Was
h off th
e
insi
de
and
ou
tsid
e of
the
fu
nnel
tra
p,
and
rem
ove
it
from
th
e fla
sk.
Add
0.25
gr
am o
f pa
per
pulp
, an
d filter
the so
lutio
n
thro
ugh
a 9-
cm fine-p
oro
sity
pape
r in
to
a 40
0-m
l b
ea
ker.
U
se
a sh
ort
stirr
ing r
od
, w
hich
sh
ould
be
ke
pt
in
the fu
nnel,
to
mak
e th
e tr
an
sfe
r.
Was
h do
wn
the
in
side o
f th
e fla
sk
thre
e
times
w
ith l-to
-19
hydro
chlo
ric
acid
, an
d tr
ansfe
r th
e w
ashe
s to
th
e filter.
F
ina
lly,
was
h th
e pa
per
five
times
w
ith
the
sam
e solu
tion,
and
dis
card
it.
3. 4.
Add
five
drop
s of
brom
cr
eso
l p
urp
le
indic
ato
r to
th
e filtra
te.
Add
1-t
o-l
hydro
chlo
ric
aci
d b
y dr
ops
un
til
the
ind
ica
tor
turn
s 20
0 m
l.
Ne
utr
aliz
e
the so
lutio
n
with
am
mon
ium
hyd
roxi
de,
yello
w;
then
ad
d 2
ml
mor
e.
Dilu
te
the solu
tion
to
Add
5 m
l of
a 10-p
erc
ent
bariu
m ch
lorid
e solu
tion.
Hea
t th
e so
lutio
n
for
2 ho
urs
on
the w
ate
r bath
, an
d stir
it
occasio
nally
d
urin
g th
is
period;
then
le
t it
sta
nd
ove
rnig
ht
at
room
te
mpera
ture
.
5.
Filte
r th
e so
lutio
n
thro
ugh
a 7-
cm fin
e-p
oro
sity
pape
r in
to
a cl
ean
150-
ml
be
ake
r.
Dis
card
ea
ch
50-m
l p
ort
ion
ot
the
filtra
te
as it
co
llects
, p
rovi
de
d it
is
cle
ar;
b
ut if
a port
ion o
f th
e filtra
te
is
turb
id,
refilter
it.
Tra
nsf
er
the
pre
cip
itate
to
th
e
pape
r usi
ng w
ate
r,
and
was
h th
e
pape
r five
tim
es
with
w
ate
r.
84
6.
Bur
n o
ff
the
pa
per
in
a w
eigh
ed
25-m
l p
latin
um
cru
cib
le ..
. H
eat
the
cru
cib
le w
ith
the
cove
r part
ially
open
ov
er
a T
irrill
bu
rne
r a
t a
du
ll-re
d
heat
for
15
min
ute
s.
Coo
l th
e cru
cib
le
in
a desi
ccato
r fo
r 30
m
inute
s,
and
wei
gh it.
(Altern
atively
, b
urn
o
ff
pape
r in
a
muffle
fu
rnace
an
d ig
nite
to
const
ant
we
igh
t a
t ~
700°
C.)
7.
Calc
ula
tions:
Wei
ght
BaS0
4 x
34.3
= p
erc
en
t $6
3.
Dis
cuss
ion
Pyrite
an
d so
me
rela
ted
min
era
ls
do
not
dis
solv
e
in
hyd
roch
loric
aci
d.
Oth
er
su
lfid
e
min
era
ls
dis
solv
e
and
libera
te
hydr
ogen
su
lfid
e,
in
som
e re
actio
ns,
pre
cip
ita
te sulfur.
Th
e ad
ded
wat
er
is firs
t b
oile
d
to
expe
l a
ir.
The
hyd
roch
loric
aci
d
is
adde
d,
and
hydr
ogen
sulfid
e,
if lib
era
ted,
is
exp
elle
d
by b
oili
ng
, w
ith
ou
t da
nger
o
f b
ein
g oxi
diz
ed
to
the
su
lfa
te.
Pyrite
an
d an
y pre
cip
itate
d su
lfu
r ar
e filtere
d
from
th
e so
lutio
n.
With
out
consi
dera
ble
kn
owle
dge
of
the
min
era
logy
of
the
sam
ple,
a
relia
ble
analy
sis
for
sulfur
trio
xid
e
cann
ot
be
mad
e.
Su
lfur
trio
xid
e
is
ge
ne
rally
p
rese
nt
as
one
or
mor
e o
f th
e
calc
ium
su
lfa
te m
inera
ls,
whi
ch
dis
solv
e re
ad
ily
in
hydro
chlo
ric acid
, an
d if
they
are
the o
nly
su
lfa
te
min
era
ls
pre
sent,
the
analy
sis
is
acc
ura
te.
Barite
an
d sca
po
lite
do
n
ot
dis
solv
e
in h
yd
roch
loric a
cid
, an
d if ro
utine
pro
cedure
s fo
r th
e d
ete
rmin
atio
n o
f sulfur
are
fo
llow
ed,
the
ir
sulfur
will
be re
port
ed
as
sulfid
e sulfur.
Th
e su
lfa
te
in
ce
lestite
is
pro
bably
in
com
ple
tely
d
isso
lve
d.
The
sulfate
co
nta
ine
d
in
alu
nite
an
d so
me
rela
ted su
lfa
te
min
era
ls
is
on
ly p
art
ly e
xtra
cte
d
by b
oili
ng
th
e
sam
ple
with h
yd
roch
loric acid
. A
lunitic
su
lfa
te
is
alm
ost
com
ple
tely
ext
ract
ed
by
bo
ilin
g
the
sa
mpl
e w
ith
5-p
erc
ent
sodi
um
hyd
roxi
de,
bu
t th
is
treatm
ent
does
not
dis
solv
e
calc
ium
su
lfa
te.
If
a m
ixtu
re of
alu
nite
and
calc
ium
su
lfa
te
min
era
ls
are
pre
sent,
the
sa
mpl
e m
ust
be b
oile
d firs
t w
ith
sodi
um h
ydro
xide
and
then
w
ith h
yd
roch
loric
aci
d
in
ord
er
to re
cove
r all
of
the
sulfate
. If
the
analy
sis
is
mad
e by
bo
ilin
g w
ith
sodi
um h
ydro
xide,
the
so
lutio
n
is filtere
d,
and
the
filtra
te
is a
cid
ifie
d w
ith hydro
chlo
ric a
cid
; th
e su
lfa
te
is
pre
cip
ita
ted
as
b
ariu
m s
ulfate
. O
nly
a fe
w
analy
ses
have
be
en
mad
e by
u
sin
g th
is
pro
ced
ure
, an
d ho
w sulfid
e
min
era
ls
are
aff
ecte
d
by
treatm
ent
with
so
dium
hyd
roxi
de
is
not
know
n.
Alth
ough
proc
edur
es
can
be
plan
ned
by
whi
ch
the va
rio
us
su
lfa
tes
and
sul f
ides
can
be
dete
rmin
ed
separa
tely
, it
is
rare
ly
ad
visa
ble
to
attem
pt
such
se
pa
ratio
ns.
Th
e to
tal
amou
nt of
sulfur
is
ge
ne
rally
so
sm
all
tha
t th
e
err
ors
in
th
e
ind
ivid
ua
l dete
rmin
atio
ns
wou
ld
be
larg
er
than
th
e sulfur
con
ten
t o
f a
part
icula
r m
ine
ral.
If
sma
ll am
ount
s of
su
lfu
r are
pre
sent, it
is
best
to
dete
rmin
e
and
report
to
tal
sulfur
and
to
allo
w
the
p
etr
og
rap
he
r to
est
imate
its
min
era
log
ica
l dis
trib
ution.
85
FIOURK 6. Spray trap. This trap, made from a transfer funnel, prevents loss spraying if a solution must be boiled.
00
TOTA
L W
ATER
-
PE
NFI
ELD
M
ETH
OD
Tota
l w
ate
r -
hyg
rosc
opic
or
su
rface
an
d oc
clud
ed
or
chem
ically
bou
nd -
is
dete
rmin
ed
gra
vim
etr
ica
lly.
The
pow
dere
d sa
mpl
e is
m
ixed
w
ith
a P
bOiP
bCrO
^CuO
flu
x
and
heat
ed
in
a M
eker
bu
rner
fla
me
. Th
e co
nden
sed
wa
ter
is
co
llecte
d
in
the
cool
p
ort
ion
of
the P
en
field
tu
be
and
wei
ghed
.
Rea
gent
s (a
ll ch
em
ica
ls-r
ea
ge
nt
gra
de):
Pre
pare
a
10+
l+l:P
bO:P
bCr0
4:C
uO f
lux
by m
ixin
g in
tim
ate
ly
and
ignitin
g
(unco
vere
d)
at
400°
C fo
r th
irty
min
ute
s.
Sto
re
in
a d
esic
ca
tor.
Pro
cedu
re
In
a sm
all
porc
ela
in
cru
cib
le,
wei
gh
0.5
0
g of
the
sam
ple
and
2.0
g
flu
x.
Mix
th
oro
ug
hly
.
Penfie
ld
tube:
dS
ampl
e b
ulb
Con
dens
atio
n bulb
2.
To
a cl
ean
dry
P
en
field
tu
be,
intr
oduce
th
e
sam
ple
and
1 flu
x m
ixtu
re w
ith
the
aid
of
a lo
ng-s
tem
fu
nnel.
The
fun
ne
l tip
shou
ld
ext
end slightly
(6-7
m
m)
into
th
e sa
mpl
e bulb
. Ta
p th
e
fun
ne
l g
en
tly
to
insu
re
a q
ua
ntita
tive
tr
ansfe
r.
3.
Rem
ove
funnel;
then
cl
ose
th
e tu
be w
ith
a sp
eci
al
ca
pill
ary
sto
pper.
C
are
mus
t be
ta
ken
so
tha
t no
ne of
the
pow
der
adhe
res
to
the
tube
w
alls
.
4.
Aro
und
the
co
ndensa
tion
bulb
, w
rap
a da
mp
clo
th
and
ca
refu
lly
pla
ce
the
tube
horizonta
lly in
to
the
sp
eci
al
ice
bath
. Th
e sa
mpl
e bu
lb
shou
ld
be
as
far
away
fr
om
the
ice
ba
th
as
poss
ible
. P
lace
a
Mek
er
bu
rne
r d
ire
ctly u
nder
th
e
sam
ple
bu
lb.
Com
men
ts
The
ratio
o
f flux
to
sam
ple
should
be
appro
xim
ate
ly
4:1
. Th
e flu
x
serv
es
to
deco
mpo
se
the
sa
mpl
e an
d re
tain
th
e vo
latile
s.
Sin
ce
the
flu
x
is slig
htly
hyg
rosc
opic
, it
shou
ld
be
ignited
eve
ry t
wo
to
thre
e
days
or
w
hen
a bla
nk
exce
eds
0.00
09
g in
w
eig
ht.
Th
e bl
ank
(consis
tin
g of
flux only
) m
ust
be
dete
rmin
ed at
reg
ula
r in
terv
als
, an
d a
fte
r ea
ch
ign
itio
n
period.
The
Pe
nfie
ld
tube
s sh
ould
be
cl
eane
d an
d st
ore
d
in
an
oven
at
105°
C.
Allo
w
the
tu
bes
to
cool
fo
r th
irty
m
inut
es
prio
r to
w
eig
hin
g
and
loadin
g th
e
sam
ple.
A
max
imum
of
fou
r dete
rmin
atio
ns
can
be
perf
orm
ed
sim
ulta
ne
ou
sly.
4.If
a su
pp
ly o
f dry
ic
e
is re
ad
ily availa
ble
, it
may
be
su
bstitu
ted
fo
r co
nve
ntio
na
l ic
e.
In
that
eve
nt,
om
it th
e
dam
p clo
th.
87
5.
Sta
rtin
g w
ith
the
sa
mpl
e bu
lb
well
abov
e th
e
flam
e (~
10
inch
es
to
1 ft.)
>
heat
g
en
tly fo
r five
min
ute
s.
Ne
xt,
low
er
the
ice
bath
an
d tu
be
ap
pro
xim
ate
ly
on
e-q
ua
rte
r th
e h
eig
ht
betw
een
the
sam
ple
bulb
an
d fla
me.
Contin
ue th
is
proc
ess
at
five
min
ute
inte
rva
ls
un
til
the
sa
mpl
e bulb
is
ju
st
abov
e th
e
blu
e
flam
e.
Thr
ough
out
the h
ea
tin
g,
lightly
tap
th
e tu
be w
ith
the
tip
s
of
a p
air
of
tongs
while
ro
tating
the
tu
be
slo
wly
to
sp
read
th
e
sam
ple
eve
nly
ar
ound
th
e
sam
ple
bu
lb.
Rep
leni
sh
ice
to
keep
th
e
cond
ensa
tion
bulb
co
vere
d a
t all
times.
Th
e to
tal
he
atin
g
proc
ess
shou
ld
be
ap
pro
xim
ate
ly th
irty
min
ute
s.
6.
Whe
n th
e pr
oces
s is
co
mple
te,
the
sa
mpl
e an
d flu
x
sho
uld
be
in
a
mol
ten
sta
te.
Usi
ng
a ga
s-ox
ygen
ha
nd
torc
h,
heat
the
sam
ple
bulb
w
hile
rota
ting
the
tube
slo
wly
. D
raw
o
ff
the
sam
ple
bulb
w
ith
a p
air of
tong
s an
d heat
the
re
ma
inin
g
end
of
the
tube
to
in
sure
pro
per
sealin
g.
Tur
n o
ff
the
Mek
er
bu
rne
r.
Do n
ot
dis
pose
o
f th
e
sam
ple
bu
lb.
7.
Allo
w
the
tube
to
co
ol
mom
enta
rily
in
th
e ic
e bath
. Ta
ke
the
tube
fr
om
the
bath
, re
mov
e th
e clo
th
and
capill
ary
sto
pper.
Im
me
dia
tely
p
lace
a
spe
cia
l d
ry
gla
ss
rod
into
th
e tu
be
and
rep
lace
th
e st
opper.
A
lway
s handle
th
e
tube
so
th
e
sto
pp
ere
d
end
poin
ts
up.
8.
Dry
th
e tu
be w
ith
a cl
ea
n
clo
th,
pla
ce it
near
th
e b
ala
nce
, an
d a
llow
th
e
tube
to
equili
bra
te
for
thirty
m
inu
tes.
H
an
dlin
g
the
tube
w
ith
cham
ois,
re
mov
e th
e st
op
pe
r an
d w
eig
h.
9.
Pla
ce
the
un
sto
pp
ere
d
tube,
conta
inin
g th
e ro
d,
in
the
ov
en
at
105°
±
5°C
fo
r a
pe
rio
d o
f a
t le
ast
two
ho
urs
.
10.
Rem
ove
the
tube
an
d ro
d
from
th
e ov
en,
pla
ce
near
th
e
ba
lan
ce,
allo
w
to equili
bra
te
for
thirty
min
ute
s,
and
weig
h.
11.
The
sam
ple
bu
lb
draw
n fr
om
the
tube
sh
ould
be
cr
acke
d op
en
and
chec
ked
for
com
plet
e d
eco
mp
osi
tion
o
f th
e sa
mpl
e (i.e
. g
lass
y su
rfa
ce
, no
lu
mps...)
.
5.
He
atin
g
the
sa
mpl
e to
o ra
pid
ly
caus
es
the
surf
ace
w
ate
r, if it
is
too
hig
h,
to
esca
pe
from
th
e
tub
e.
The
hand
to
rch
m
ay b
e us
ed
anyt
ime
aft
er
fift
ee
n
min
utes
in
to
the
h
ea
ting
pr
oces
s to
pr
omot
e m
elti
ng
o
f th
e
pow
der.
W
hen
the
to
rch
is
us
ed,
be
sure
to
ro
tate
th
e
tube
to
ke
ep th
e re
d-h
ot
gla
ss
fro
m
sagg
ing
and
to
avo
id ru
ptu
rin
g th
e
sam
ple
bulb
.
7.
The
gla
ss
rod
sh
ou
ld fit
the
tu
be
snu
gly
bu
t perm
it th
e
repla
cem
ent
of
the
st
op
pe
r.
The
rod
se
rves
to
dis
pla
ce
C02
fr
om
th
e
tub
e.
9.
Ove
rnig
ht
is
conve
nie
nt.
10.
The
diffe
ren
ce
in
th
e
two
weig
hts
o
f th
e
tube
(w
eig
ht
in
ste
p
no.
8 -
we
igh
t in
st
ep
no.
10)
rep
rese
nts
(t
he
ore
tica
lly)
the to
tal
wa
ter
con
ten
t o
f th
e
sam
ple
(less
th
e H
£0
in
the bla
nk).
P
erc
en
t to
tal
H20
=
(diffe
rence
in
weig
ht
- bl
ank
H20
w
eig
ht)
(10
0 perc
ent)
Wei
ght
of
Sam
ple
Com
pile
d by
J.
R
ivie
llo88
REFE
RENC
ES
1.
Hill
ebra
nd,
W.
F.,
L
un
de
ll,
G.E
.F.,
B
right,
M.
S.,
an
d H
offm
an,
1953
, A
pplie
d
Inorg
anic
A
naly
sis,
2n
d e
d.:
Ne
w Y
ork,
Jo
hn
Wile
y an
d S
ons,
In
c.,
p.
814-8
35.
2.
Ko
lth
off
, I.
M.,
Sandell,
E.
B
.,
Mee
han,
E.
0
.,
and
Bru
ckenst
ein
, S
tan
ley,
19
69,
Quantita
tive
Che
mic
al
Analy
sis,
4th
e
d.:
T
oro
nto
, C
olli
er-
Ma
cm
illa
n C
anad
a,
Ltd
.,
p.
573-
579.
89
AC
ID
DE
CO
MP
OS
ITIO
N
FOR
ATO
MIC
A
BS
OR
PTI
ON
A
NA
LYS
IS
An
aci
d
brea
kup
of
rock
s an
d m
ine
rals
is
p
refe
rre
d
whe
n tr
ace
s ar
e to
be
anal
yzed
by
ato
mic
abso
rptio
n.
The
tota
l d
isso
lve
d so
lids
are
decr
ease
d w
ith
conco
mita
nt
dim
inutio
n
of
vario
us
inte
rfere
nces.
The
sam
ple
is
heat
ed in
itia
lly
in
equa
l vo
lum
es
of
HNOQ
, H
C10
4,
and
H/F
. Th
e so
lutio
n
is
eva
pora
ted
to
dry
ne
ss,
take
n up
in
eq
ual
volu
mes
of
HNO?
an
d H
C10
4,
and
agai
n eva
pora
ted
to
dry
ness
. Th
e d
rie
d solid
s
are
heat
ed
in
1+1
HC1
and
mad
e to
vo
lum
e.
Pre
limin
ary
run
s of
the r
eq
ue
ste
d
elem
ents
on
th
e
ato
mic
abso
rptio
n
are
mad
e to
de
term
ine
if dilu
tion
is
ne
cess
ary
.
Pro
cedu
re
1.
Wei
gh
1.0
0
g ea
ch
prem
ixed
sa
mpl
es
and
transfe
r to
te
flon
cru
cib
les.
At
the
sa
me
time,
pre
pa
re
3 or
4 ro
ck
sta
nd
ard
s co
vering
a sp
an
of
conce
ntr
atio
ns.
2.
Add
in
the
follo
win
g
ord
er:
10 m
l 10
ml
10 m
l
HN0
3H
C10
4HF
At
the
sa
me
time
, p
rep
are
an
a
cid
bla
nk.
3.
Cov
er
and
pla
ce
on
hot
pla
te w
ith
surf
ace
te
mp
era
ture
se
t a
t ~1
00°C
. Le
t st
and overn
ight.
4.
Cool.
Rem
ove
cove
rs
and
was
h do
wn
sides
and
cove
rs
with
a m
inim
um o
f w
ate
r.
Ret
urn
the
cru
cib
les
to
the
ho
t p
late
. G
radually
in
cre
ase
th
e
surf
ace
te
mp
era
ture
to
~2
25°C
.
5.
Co
ntin
ue
heatin
g u
ntil
cruci
ble
s ce
ase
fum
ing
. C
ool
and
was
h do
wn
the
si
des
of
the
cru
cib
les
with
a
min
imum
of
wa
ter.
Ad
d 10
ml
HN
03
and
10 m
l H
C10
4.
6.
Ret
urn
cru
cib
les
to
hot
pla
te.
Take
to
th
e ce
ssatio
n
of
fum
es
again
.
7.
Co
ol.
Was
h do
wn
the
sid
es
of
the
cru
cib
les
with
H
20.
Add
10 m
l o
f 1+
1 HC
1 to
ea
ch.
Tra
nsf
er
the
con
ten
ts quantita
tively
to
pv
rex
beak
ers
and
pla
ce
on
stea
m b
ath
to
com
plet
e d
isso
lutio
n.
Che
ck
for
resi
dues.
Com
men
ts
1.
The
sam
ple
size
m
ay b
e re
duce
d w
ith
a co
rre
spo
nd
ing
de
crea
se
in
volu
me
depe
ndin
g up
on
the
num
ber
of
ele
me
nta
l an
alys
es
request
ed.
Roc
k st
andard
s ar
e us
ed
to
chec
k th
e calib
ration
curv
e,
or
mig
ht
even
be
ne
eded
to
co
nst
ruct
th
e
curv
e.
2.
HN03
m
ust
alw
ays
be
adde
d firs
t to
oxid
ize
any
org
anic
m
ate
rial
pre
sent.
HC
104
can
be h
igh
lye
xplo
sive
in
th
e
pres
ence
of
org
anic
mate
rial.
4.
Teflo
n
has
rath
er
poor
d
ime
nsi
on
al
sta
bility
even
at
room
te
mp
era
ture
. As
te
mpera
ture
is
ra
ised,
its
resi
stance
to
d
efo
rma
tion
de
crea
ses
rap
idly
. A
t te
mpera
ture
s ab
ove
285°
C,
it m
ay
be
gin
to
de
com
pose
.
5.
Heatin
g to
fu
me
cess
atio
n
resu
lts
in
the r
emov
al
of
Si
as
gase
ous
SiF
4.
7.
Ofte
n th
e re
sid
ue
, w
hen
filtere
d,
was
hed,
an
d w
eigh
ed
is neglig
ible
; e
.g.
< a
few
m
illig
ram
s;
i.e
. a
few
p
art
s in
a
thousa
nd.
8.
Coo
l an
d m
ake
to
100
ml
in
volu
metr
ic flasks.
9.
Run
th
e so
lutio
ns
on
the
ato
mic
a
bso
rptio
n
to
de
term
ine
w
hat
dilu
tio
ns
are
required.
10.
Pre
pare
th
e
nece
ssary
d
ilutio
ns
endeavo
ring
to h
ave
the
co
nce
ntr
atio
ns
pro
vid
e b
etw
een
30
and
50 perc
ent
abso
rptio
n.
Als
o
pre
pare
st
an
da
rds
from
"p
ure
" solu
tions
matc
hin
g
the
de
nsi
ty
to
the
sa
mpl
es
by
usi
ng
th
e
ap
pro
pria
te
aci
ds.
11.
Aft
er
de
term
inin
g
abso
rban
ce
on
the
AA
, pre
pare
a
ca
libra
tio
n
curv
e
by
the
least
squa
res
met
hod
usi
ng
th
e
"pu
re"
standard
s d
ata
. C
ompu
te
the
co
nce
ntr
atio
n
in
ppm
(m
icro
gram
pe
r gr
am)
in
the
ro
ck
sta
nd
ard
solu
tions.
Che
ck
the
co
nce
ntr
atio
ns
again
st
the
re
com
men
ded
valu
es.
12.
If
the
co
nce
ntr
atio
ns
of
rock
st
andard
s do
no
t ag
ree
with
in
±10
pe
rce
nt
with
th
e
reco
mm
ende
d va
lue
s,
pre
pare
a
ca
libra
tio
n
curv
e usi
ng
the
w
eig
ht-
co
rre
cte
d ro
ck
sta
nd
ard
s d
ata
.
13.
If th
e
rock
st
an
da
rd
data
do
not
prod
uce
a re
aso
nably
str
aig
ht
line
no
r an
a
cce
pta
ble
cu
rve
, th
e m
etho
d of
standard
additio
ns
mus
t be
us
ed.
9.
An e
ffo
rt
sho
uld
be
m
ade
to
redu
ce
the
nu
mbe
r of
dilu
tions
for
the diffe
rent
elem
ents
to
as
fe
w
as
po
ssib
le.
10.
The
upta
ke ra
te
on
the
AA is
dete
rmin
ed b
y th
evis
co
sity o
f th
e solu
tions.
A d
iffe
ren
ce
>
1 p
erc
en
t be
twee
n st
an
da
rds
and
sam
ples
le
ads
to err
or.
12.
If
agre
emen
t is
no
t w
ith
in
±10
perc
ent,
there
are
m
atr
ix
inte
rfere
nces.
"Pu
re"
solu
tion
standard
s ca
nnot
be
us
ed fo
r th
at
ele
me
nt.
13.
See
An
aly
tica
l M
etho
ds
For
Fl
ame
Spect
rosc
opy,
V
aria
n
Tech
tron,
pp.
14
-15
.
Mic
ro p
ipe
tte
s
sho
uld
be
us
ed.
Vol
ume
chan
ges
are
ne
glig
ible
th
en,
and
the
met
hod
seem
s to
pr
oduc
e b
ett
er
resu
lts.
Var
ian
reco
mm
ends
th
is.
Com
pile
d by
M
. C
rem
er
91
DETERMINATION
OF BORON
IN SILICATES
(From
Determination
of Bo
ron
in Silicates
after
Ion
Exchange Separation,
Henr
y Kramer,
Anal
. Chem., v.
27,
no.
-1,
Janu
ary
1955
, p. 144-145.
The
sample is fused
with so
dium
carbonate,
acid
ifie
d with hydrochloric ac
id,
filtered,
neut
rali
zed
with sodium
hydroxide, an
d the
solu
tion
el
uted
from an io
n ex
chan
ge column.
Boro
n is
determined ti
trim
etri
call
y in th
e presence
of m
anni
tol
usin
g a
pH m
eter
to
indicate the
end
poin
t.
Reagents (a
ll ch
emic
als-
reag
ent
grad
e):
Mann
itol
, ne
utra
l, boron-free.
Ambe
rlit
e IR
120(H) -
exchange c
apacity
of th
e dr
y resin
appr
oxim
atel
y eq
ual
to 5
mg
per
gram
.
Sodium h
ydro
xide
, 20
per
cent
w/v
carbonate free.
Sodium h
ydroxide,
0.05
N st
anda
rdiz
ed w
ith
KH(1
03)2
, and
methyl red
as indicator.
Proc
edur
e
Fill with wa
ter
a borosilicate chromatograph
tube
20 x
400
mm.
Add
slowly a
slur
ry o
f th
e resin
to a
colu
mn le
ngth
of
10 in
ches
. The
column should be
free
of
air
spaces.
2.
Before using, wash the
column with 100
ml of
hydrochloric acid an
d follow w
ith
50 m
l portions of
water
until
effl
uent
gi
ves
a negative te
st for
chlorides.
Comm
ents
The
resin
may
be r
egenerated after
use
by
tran
sfer
ring
accumulated
resin
from
a number o
f de
term
inat
ions
to
a
larg
e glass
tube an
d washing
with
1+9
HC1
unti
l the
rins
es give a
nega
tive
test
for
adsorbed ions.
HC1
is re
move
d by
washing w
ith
wate
r.
A si
lver
ni
trat
e cr
ysta
l may
be us
ed to
test
for
chlo
ride
s.
92
3. 4. 5.
Weigh
suff
icie
nt sa
mple
no
t to ex
ceed
1
gram b
ut
which
contains no m
ore
than
20
mg
6203
in
to a
plat
inum
crucible.
Also w
eigh a
portion
of NBS
93,
a borosilicate gl
ass,
as
a control.
Add
six
time
s th
e sa
mple
weight o
f anhydrous
sodium
carbonate
and
mix
intimately.
Cover
the
crucible,
fuse
, co
ol,
and
plac
e th
e crucible in a
150-ml be
aker
co
ntai
ning
20
ml of
wat
er.
Cover
the
beaker wi
th a
watch
glas
s an
d ad
d co
ncen
trat
ed HC1
down
th
e si
de o
f the
beak
er un
til
there
is an ex
cess
of 1
ml over the
theoretical
amou
nt ne
eded to decompose
the
carbonate.
When
th
e re
acti
on ha
s ceased,
diss
olve
an
y carbonate
adhering t
o the
cruc
ible
or
cove
r with dilute HC1.
Remove an
y ad
heri
ng m
aterial
with
a ru
bber
policeman
and
rinse
into the
beak
er w
ith
a stream o
f H2
0.
Filt
er th
e mi
xtur
e th
roug
h 9
cm W
hatman 4
1H f
ilte
r pa
per
and
wash with ho
t H2
0 to a
volu
me o
f ab
out
50
ml.
Neut
rali
ze the
above
solution until
a precipitate
just
beg
ins
to fo
rm.
Add
concentrated HC1
dropwise
until
the
prec
ipit
ate
just di
ssol
ves.
NBS
93 co
ntai
ns 12.76
perc
ent
8203.
Ther
efor
e,
wher
e x
= samp
le we
ight
, solve
the
following
equation
for
x. (0
.1
276)
(x m
g) =
20 m
g B2
03;
x =
156.
7 mg
, a weight not
to be exceeded.
0.05
N
NaOH is to
be
us
ed subsequently in th
e titration.
Since
1 ml
0.
05 N
NaOH =
1.741
mg 6203,
and
a microburet
cali
brat
ed to
0.
02 m
l (1
0 ml
capacity)
is to
be used,
it is
wise to calculate
samp
le weight m
ore
exactly
as
foll
ows:
x =
samp
le w
t.
(.1276)(x
mg)
= 9.
5 ml
1.741
mg/ml
x =
129.
6 mg
NBS93
or less depending
upon th
e volume of
Na
OH desired.
This ca
lcul
ation
insu
res
that
th
e microburet ne
ed not
be fi
lled
twice.
Also,
this
amount of
sa
mple
mee
ts
the
requirement
of <2
0 mg
6203.
5.
Na2C
03H2
0CO
2'
93
9.
Pou
r th
e so
lutio
n
thro
ug
h
the
ion
exch
ange
co
lum
n in
to
a 40
0-m
l be
aker
an
d fo
llow
w
ith
fou
r 50
-ml
port
ions
of
wa
ter,
ad
ding
mor
e w
ash
wa
ter
whe
n th
ere
is
0.5
in
ch
of
sup
ern
ata
nt
solu
tion
in
the
re
sin
. A
dju
st
the
flow
ra
te
so
that
the
tota
l el
apse
d tim
e
for
the
solu
tion
and
4 w
ashi
ngs
is
15
min
utes
or
16.7
m
l pe
r m
inu
te.
10.
Add
2 or
3
drop
s of
met
hyl
red
ind
ica
tor
to
the
solu
tion
and
mak
e a
lka
line
w
ith
20
perc
ent
sodi
um
hyd
roxi
de
and
then
bare
ly
aci
d w
ith
conce
ntr
ate
d
HC
1.
11.
Cov
er
the
be
aker
w
ith
a w
atch
g
lass
an
d b
oil
for
3 to
5
min
utes
to
re
mov
e C
02.
Coo
l to
ro
om
tem
pera
ture
in
a
wate
r bath
.
12.
Pla
ce
the
pH
met
er
ele
ctro
de
s an
d a
stirr
er
into
th
e
beak
er
and
ad
just
th
e
pH o
f th
e so
lutio
n
to 7.0
with
0.
05
N Na
OH.
13.
Add
40
gram
s o
f m
an
nito
l an
d,
with
a
mic
rob
ure
t,
titr
ate
ra
pid
ly w
ith
0.0
5
N Na
OH u
ntil
the
pH
appr
oach
es
7 an
d th
en
slo
wly
nea
r th
e en
d p
oin
t,
thus
allo
win
g fo
r an
y slig
ht
lag
in
m
eter
re
spo
nse
.
14.
Whe
n th
e re
adin
g
rem
ains
st
eady
at
7.0
for
at
lea
st
10
seco
nds,
re
cord
th
e
volu
me
of
standard
ba
se
used
.
15.
Pre
pare
an
d dete
rmin
e
the
rea
ge
nt
bla
nk.
S
ubtr
act
th
e
bla
nk
titr
atio
n
from
th
e
sam
ple
titr
ation.
Calc
ula
te
perc
ent
8203
u
sin
g
1 m
l 0.0
5
N Na
OH
= 1.
741
mg
6203
.
At
the
co
ncl
usi
on
of
the
fin
al
was
hing
, th
e efflu
ent
should
be
o
nly
slightly
aci
d
to
pH
pa
pe
r.
12.
The
readout
sho
uld
be
st
ea
dy
at
7.0
.
13.
Mannito
l w
ith
its
mu
ltip
le
hyd
roxy
l gr
oups
co
nve
rts
the
wea
k boric
aci
d
into
a
rela
tive
ly st
ron
g
acid
, th
us
perm
itting
a m
ore
acc
ura
te titr
atio
n.
15.
The
bla
nk
is
usu
ally
<
0.10
m
l o
f 0.
05
N Na
OH,
Com
pile
d by
M.
Cre
mer
REFERENCES
Hill
ebra
nd,
W. F.,
Lund
ell,
G.E.F.,
Bright,
H. A.,
Hoffmann,
J. I.,
1953,
Appl
ied
Inorganic
Analysis,
2nd
edition,
John
Wiley
a Sons,
Inc.,
New
York
.
Kolt
hoff
, I.
M.
, Sandell, E. B.,
Meehan,
E. J.,
Bruckenstein,
Stan
ley,
19
69,
Quan
tita
tive
Che
mica
l An
alys
is,
4th
edition,
The
Macmillan
Company, Collier-Macmillan
Cana
da,
Ltd.
, To
ront
o, Ontario, p.
78
3, 78
7-78
8.
95
CAR
BON
ATE
CARB
ON
IN
SIL
ICA
TE
S,
CAR
BON
ATES
, AN
D PH
OSP
HAT
ES
Car
bona
te
carb
on,
als
o re
ferr
ed
to
as
aci
d
solu
ble
or
inorg
anic
ca
rbo
n,
is
dete
rmin
ed
usi
ng
a C
02
coulo
mete
r.
The
coul
omet
er ce
ll is
filled w
ith
a p
art
ially
aque
ous
med
ium
co
nta
inin
g
mon
oeth
anol
amin
e an
d a
col c
rim
etr
ie
indic
ato
r.
Whe
n th
e lib
era
ted
a
cid
-so
lub
le
C02
is
pa
ssed
th
rou
gh
th
e solu
tion,
C02
is quantita
tively
ab
sorb
ed
and,
up
on
rea
ctio
n w
ith
mon
oeth
anol
amin
e,
is
con
vert
ed
to
a
stro
ng titr
ata
ble
acid
, ca
usi
ng
the
blu
e
indic
ato
r co
lor
to
fad
e.
The
coulo
mete
r ele
ctr
ically
gene
rate
s ba
se
to re
turn
th
e co
lor
to
its
origin
al
inte
nsity.
The
coul
omet
er
dis
pla
ys
un
its
of
yg
C02»
Th
e ac
cura
cy is
0.
1 perc
ent
for
sam
ples
co
nta
inin
g
ove
r 1
mg
carb
on.
A m
ore
com
plet
e description
and
insta
llatio
n
proc
edur
e ca
n be
fo
und
in
man
ual}.
Pro
cedu
re
1.
Fre
shly
fill
the
pe
rtin
en
t tu
bes
as
follo
ws:
A.
Fill
air
scru
bb
er
tube
w
ith
ap
pro
x.
12
ml
of
45
pe
rce
nt
KOH.
B.
Fill
sam
ple
scru
bb
er
tube
with
ap
prox
. 3
ml
of
1 perc
ent
AgC
104
and
0.3
m
l H
202-
2.
Cell
Filling:
A.
Pla
ce
appro
xim
ate
ly 7
0 m
l of
coulo
mete
r so
lutio
n
in
the
cell
body
(b
eake
r).
The
entire
lig
ht
beam
m
ust
pass
th
rou
gh
so
lutio
n.
Mak
e su
re suffic
ient
so
lutio
n
is
used
so
th
at
the stirr
ing v
ort
ex
will
not
be
in
the
lig
ht
beam
.
B.
Add
stirr
ing
bar.
C.
Be
sure
ce
ll ca
p is
a
pp
rop
ria
tely
as
sem
bled
(Fig
ure
II
re
prod
uced
fr
om
the
instr
uction
man
ual
and
attach
ed).
D.
Pla
ce
a fe
w
cry
sta
ls
of
KI
insid
e
the
an
ode
com
part
men
t.
E.
Pla
ce
cell
cap
on
the ce
ll bo
dy
and
add
anod
eso
lutio
n
to
the
anod
e co
mpa
rtm
ent
so
that
whe
n th
e
silv
er
ele
ctro
de
is
in
pla
ce,
the
an
ode
so
lutio
n
leve
l w
ill
be
the
sam
e as
th
e solu
tion
leve
l in
th
e ce
ll bo
dy,
and
the
e
lect
rod
es
are
tilte
d
back
to
war
d th
e
lab
elin
g
on
the
ce
ll bo
dy.
Comm
ents
1. Th
e KO
H removes
C02
from t
he c
arri
er ai
r.
Ifexcessive
foaming
occu
rs,
add
a fe
w dr
ops
of H2
0 or
re
plac
e th
e KO
H.
96
F. Pl
ace
cell in
cou
lome
ter
cell holder w
ith
the
electr
odes to t
he b
ack.
G. Be s
ure
cell cu
rren
t sw
itch
is off.
coulom
eter
.Tu
rn o
n
H. The
anod
e compartment
frit
an
d gas
inle
t tu
be
shou
ld b
e po
siti
oned
so t
hat
they
are j
ust
abov
e th
e stirrer
but
in b
ack
of the
ligh
t be
am.
This
ma
y be c
heck
ed b
y ro
tati
ng the
cell until
maxi
mum
Perc
ent
T is o
bser
ved.
The
Pt e
lectrode s
houl
d project
out
and
just
in the
light
beam f
or the
highest
sens
itiv
ity.
I. The
Perc
ent
T kn
ob sh
ould
be
adjusted t
o gi
ve ab
out
100
perc
ent
T (this
sett
ing
is no
t hi
ghly
cri
tica
l,
but
must
no
t be c
hang
ed d
uring
analysis).
If th
e Pe
rcen
t T
mete
r is not
stea
dy,
check
to s
ee t
hat
the
gas
stre
am is
bu
bbli
ng a
way
from t
he light
beam
,
J. Plug in
electrodes
noti
ng po
lari
ty (c
atho
de-b
lack
, anode-red).
3. Fill ac
id dispenser
bott
le w
ith
2N H
C104
; ch
eck
delivery s
yrin
ge f
or 2
ml.
4. Tu
rn o
n cell current, heater (a
2:00
o'clock
sett
ing)
, an
d air
pump (s
et rotometer
at 10
0 cc/min).
5. Allow
the
coulometer to
titrate
to t
he e
nd po
int
and
to s
tabi
lize.
Chec
k for
leak
s if
stabilization does
not
occur.
6. Reset
coun
ter.
7. Weigh
a sample in
a
porc
elai
n bo
at o
r ot
her
carbonate
free
samp
le c
arrier an
d dr
op e
ntire
carrier
into
samp
le t
ube.
Norm
ally
sam
ple
size
is selected so
th
at
1 to
3 m
g of
carbonate ca
rbon
is
evo
lved
(i.e., 100
mg
SCo-1
gives
2500
yg
C0£
or 2
.50
percent
acid-soluble
C02)
.
3. Pe
rchl
oric
acid is
no
n-ox
idiz
ing
in d
ilut
e solution.
Care
sho
uld
be e
xercised t
o avoid
concentrating
the
acid
.
5. Ty
pica
lly
this takes
2-5
minutes
and
depends
upon
the
am
ount
of
C0£
abs
orbe
d by
the
system
and
the
solu
tion
s, as
th
e equipment
was
bein
g pr
epar
ed for
oper
atio
n.
7. At
hig
h cu
rrent
(100 m
a),
750
micrograms/minute
of
carbon is ti
trat
ed.
97
8. Reconnect
the
sample tube an
d allow
syst
em t
o purge
the
C02
whic
h en
tere
d while
the
samp
le tube w
as
disconnected.
9. Reset
coun
ter.
10.
Press
plun
ger
to dispense about
2 ml
acid.
11.
Rota
te tube onto h
eater.
12.
Allo
w samp
le to purge
until
coul
omet
er g
ives a
relatively s
table
reading.
Reco
rd r
eadi
ng and
disp
ose
of s
ample
and
acid.
13.
Reset
coul
omet
er an
d run
next
sa
mple
(s
tep
No.
7).
14.
Calculation:
(Mic
rogr
ams
C -
blank) x
100
Micrograms sample
= Percent
carb
onat
e ca
rbon
(C02
)
14.
Norm
ally
the
blank value
is ne
glig
ible
(4pg C0
2 in
2500 yg
), but
should b
e recorded fo
r low-level
work
.
15.
Cell
Changing an
d Clean-up:
The
cell so
luti
ons
shou
ld b
e ch
ange
d daily
even when
use
is light.
Cell solutions
should b
e re
plac
ed if
over 100 mg o
f carbon have been ti
trat
ed.
A. Turn of
f cell cu
rren
t an
d coulometer power.
B. Unplug electrodes an
d re
move
cell fr
om h
older.
C. Di
spos
e of c
oulo
mete
r so
luti
on an
d rise cell bo
dy.
D. Re
move
silver el
ectr
ode
and
rinse
with w
ater
.
E. Rinse
outside
of a
node
compartment, gas
inle
t tu
be,
and
Pt el
ectr
ode
with w
ater
.
F. Rinse
out
the
anod
e co
mpar
tmen
t with ac
eton
e.
Use
test
tube brush
to r
emove
KI and
depo
sits
on
top
of
the
glass
frit if
necessary.
15.
The
valv
e on
the
flow m
eter
sh
ould
be
closed (flow
turn
ed o
ff)
before the
pump is
tu
rned
of
f.
This wi
ll
elim
inat
e the
possibility
of K
OH b
eing f
orce
d back
into
th
e pump.
98
G. Pull ac
eton
e through
frit
with aspirator
or ot
her
vacu
um s
ource.
If ac
eton
e do
es no
t fl
ow t
hrou
gh
the
frit rapidly, the
frit sh
ould
be
more
thoroughly c
leaned or r
eplaced.
Anode
depo
sits
ca
n be
rem
oved w
ith
a saturated
KI so
luti
on.
H. If a
deposit
is eyident
on the
plat
inum
ele
ctro
de,
this should be
di
ssol
ved
in 1:1
HN03.
Prev
ent
depo
sits
by n
ot leaving
the
cell assembly s
tand
ing
unused o
vernight o
r for
extended periods
when it is
filled.
I. Dry
all
comp
onen
ts.
16.
When an
alys
is is co
mple
te:
A. Drain
air
scrubber,
rinse
with h^O, then 1+1
HC1,
then finally
with h^O
again.
B. Drain
sample sc
rubb
er,
rins
e with h^
O, then wa
rm
usin
g wa
ter
bath
with NfyOH
in sc
rubb
er (t
o clean
frit),
and
finally
rinse
with
H2
0 again.
Compiled b
y P.
Klock
99
FIG
UR
E II
C
OU
LOM
ETER
C
ELL
DE
TE
1C
TO
R
CE
LL
LIG
HT
50
UR
CE
a.
Ce
ll bo
dyb
. C
ell
cap
c.
Gas
in
let
d.
Gas
outlet
e.
Ano
de
com
part
men
tf.
S
tirr
erg.
P
latin
um
e
lect
rod
e
(cath
ode)
h.
Silv
er
ele
ctro
de
(ano
de)
i.
Lig
ht
path
100
REFE
RENC
ES
1.
Coulo
metr
ics
Inco
rpo
rate
d
Instr
uctio
n
Man
ual,
P.O
. Bo
x 54
4,
Whe
at
Rid
ge,
Col
orad
o 80
033.
101
TOTA
L CA
RBO
N C
ON
TEN
T O
F G
EOLO
GIC
M
ATE
RIA
LS
A Le
co
WR
-12
with
an
in
duct
ion
furn
ace
is
us
ed
in
a co
mbust
imetr
ie
de
term
ina
tion
of
tota
l ca
rbon
in
ro
cks^
. A
ther
mal
conductivity cell
is
the
sensi
ng
devi
ce,
with
tw
o in
stru
me
nt
rang
es
of
0.00
5 p
erc
en
t -
0.2
0
pe
rce
nt
C an
d 0.
01
pe
rce
nt
- 5
.0 p
erc
en
t C
. Up
to
1.0
gra
m o
f po
wde
red
sam
ple
(<10
0 m
esh)
m
ay b
e us
ed,
depe
ndin
g on
th
e
amou
nt of
carb
on
.
Appro
xim
ate
ly 2
0-25
sa
mpl
es
can
be
anal
yzed
in
4
ho
urs
. A
deta
iled
dis
cuss
ion
o
f eq
uipm
ent
may
be
foun
d in
R
efer
ence
s 2
and
3.
1.
Pre
pare
pr
emix
ed
-100
mes
h sa
mpl
e so
th
e w
eig
ht
corr
espo
nds
to
the
expe
cted
pe
rcen
tage
of
carb
on
in
the
sa
mpl
e (u
se
Tab
le
1).
2.
Qu
an
tita
tive
ly
load
th
e w
eigh
ed
sam
ple
into
a
'Le
co'
cru
cib
le
and
cove
r w
ith
a la
bele
d w
atch
gla
ss.
To
min
imiz
e
con
tam
ina
tion
, ha
ndle
'L
eco
' cru
cib
le w
ith
ton
gs.
3.
Per
form
an
ele
ctr
on
ic
chec
kout
of
the
in
stru
me
nt.
A.
Che
ck
to
see
that
Pow
er
On lig
ht
is
on.
It
mus
t ha
ve b
een
on fo
r 4
ho
urs
.
B.
Clo
se
the positiv
e-lockin
g tr
ay o
f th
e
induct
ion
furn
ace
.
C.
Tur
n on
ox
ygen
ta
nk.
S
et
Re
gu
lato
r at
35 psi.
Dep
ress
02
sw
itch
. S
et
the
ox
ygen
flo
w
at
1.5
on
the
roto
mete
r.
Oxy
gen
mus
t be
on
fo
r 10
min
ute
s.
D.
Tur
n th
e C
arbo
n R
ange
sw
itch
to
0.
0050
to
0.
200
pe
rce
nt
C p
ositio
n
and
turn
th
e B
lank
sw
itch o
ff
(not
glo
win
g).
E.
Tur
n th
e fu
nction
Sele
ct
Sw
itch
to
DVM
Zer
o p
ositio
n
and
with
a
sma
ll sc
rew
d
rive
r a
dju
st
the
DVM
to
re
ad
0.00
0 ±
0.0
01.
(The
adju
stm
ent
is
acc
ess
ible
th
roug
h a
smal
l hole
in
th
e
DVM
win
dow
.)
F.
Ope
n th
e
ele
ctr
onic
s
dra
wer.
G.
Plu
g te
st
lead
in
to
Tex
t Ja
ck
sock
et
of
the
DV
M;
plu
g
the oth
er
end
(red w
ire)
into
th
e
+15
and
the
com
mon
te
st
poin
ts.
DVM
sh
ould
rea
d B
etw
een
+0.1
475
and
+0.
1525
. If
not,
ad
just
R
14
on
the
± 15
VD
C ca
rd.
H.
Plu
g te
st
lead
in
to
-15
(Red
w
ire)
and
com
mon
te
st
po
int.
DV
M sh
ou
ld
read
be
twee
n -0
.14
75
an
d -0
.1525.
If
no
t,
adju
st
R13
lo
cate
d
on
the
* 15
vo
lt
card
.
102
I.
Dep
ress
th
e
Sta
nd-b
y sw
itch
. P
lug
test
lea
d
into
B
ridge
te
st
po
ints
. DV
M sh
ou
ld
rea
d
betw
een
± 0.
0580
an
d ±
0.0
620.
If not,
ad
just
the
Brid
ge
Cu
rr.
contr
ol
loca
ted
on
the
function
ad
just
p
an
el.
If
ad
just
me
nt
need
ed,
wa
it 10
min
utes
fo
r sta
biliz
ation.
J.
Rem
ove
test
lead
from
te
st
po
ints
an
d te
st
plu
g
from
T
est
Ja
ck.
Clo
se ele
ctr
onic
d
raw
er.
K.
Dep
ress
S
tand-b
y sw
itch
. T
urn
Fu
nct
ion
S
ele
ct
switc
h
to
Pre
-am
p Z
ero
po
sitio
n.
DVM
sh
ould
re
ad
betw
een
+0.
006
and
-0.0
06.
If not,
ad
just
P/A
B
al
co
ntr
ol
on
the
fu
nctio
n
ad
just
p
an
el.
L.
Dep
ress
th
e S
tand-b
y sw
itch.
Tur
n th
e F
un
ctio
n
Se
lect
sw
itch
to
th
e T
/H
Bal
ance
p
ositio
n.
Obs
erve
DV
M fo
r a
t le
ast
one
min
ute
. It
sho
uld
re
ad
betw
een
+0.
006
and
-0.0
06.
If n
ot,
se
t th
e
T/H
B
al
contr
ol
on
the fu
nctio
n
adj.
pane
l as
se
t fo
rth
on
p.
4-1
, no
. 7
of
instr
uctio
n
man
ual
.2
M.
Dep
ress
th
e S
tand-b
y sw
itch.
Turn
th
e F
unct
ion
Se
lect
sw
itch
to
th
e In
teg
Bal
p
ositio
n.
DVM
sh
ould
re
ad
be
twee
n +
0.00
6 an
d -0
.00
6.
If
no
t,
ad
just
Int-
Ba
l co
ntr
ol
on
fun
ctio
n
ad
just
pa
nel
un
til
0.00
0 is
ach
ieve
d.
N.
Tur
n F
un
ctio
n
Se
lect
sw
itch
to
Brid
ge
positio
n.
DVM
sh
ould
re
ad
betw
een
+0.
0020
an
d -0
.00
20
. If
not,
ad
just
B
rid
ge
B
al
contr
ol
loca
ted
on
fu
nct
ion
ad
just
p
an
el,
If
ad
just
me
nt
need
ed,
wait
10 m
inut
es
for
sta
biliz
atio
n.
0.
Dep
ress
S
tand
-by
switc
h.
Set
R
ange
sw
itch
to hig
h
rang
e p
ositio
n.
Tur
n F
un
ctio
n
Sele
ct
switc
h
to
Ope
rate
positio
n
for
ap
pro
xim
ate
ly
30
seco
nds.
No
w tu
rn
Fu
nct
ion
S
ele
ct
switc
h
to
Inte
g
Che
ck
positio
n
and
note
tim
e.
At
end
of
one
min
ute
, note
re
ad
ing
. DV
M m
ust
not
chan
ge
mor
e th
an
±0
.00
1.
4'
Dep
ress
F
ilam
ent
Volta
ge.
5.
Rot
ate
Funct
ion
Sele
ct
switc
h
to C
alib
rate
p
ositio
n.
6.
Aft
er
one
min
ute
, de
pres
s H
igh
Volta
ge.
7.
Po
sitiv
e-lo
ckin
g tr
ay o
f in
duct
ion
furn
ace
sh
ould
still
be
clo
sed
.
8.
Che
ck
tha
t co
mbu
stio
n tim
e
is
70
seco
nds.
9.
Sam
ple
we
igh
t co
mpe
nsat
or
shou
ld
read
1.0
00
gram
s.
10.
Dep
ress
st
an
db
y.
Tur
n o
ff
Bla
nk
switc
h if it
is
on
(off=
not
glo
win
g).
11.
Load
in
to
'Lec
o1
cru
cib
le
one
scoo
p o
f Cu
a
cce
lera
tor
and
one
scoo
p o
f Fe
ch
ips
(Cu
on
bottom
).
Pre
pare
severa
l;
thes
e w
ill
be
the b
lanks
.
12.
Pla
ce
a b
lan
k on
p
ed
est
al;
clo
se
and
lock
p
ositiv
e-lo
ckin
g lo
ad
ing
tr
ay.
103
13.
For
lo
w-s
cale
opera
tion
(0.0
05-0
.20
pe
rce
nt
C),
pr
ocee
d directly to
N
o.
31.
14.
Car
bon
Ran
ge
switc
h
shou
ld
be
on
0.0
10
to
5.0
00
pe
rce
nt
C positio
n.
15.
Aft
er
appro
xim
ate
ly
30
sec,
de
pres
s th
e
gree
n analy
ze
switc
h.
16.
Aft
er
the
carb
on
indic
ato
r tu
rns
white
an
d th
e
Ana
lyze
go
es off,
unlo
ad
the
ho
t cru
cib
le
and
pla
ce
anoth
er
bla
nk
on
the
pedest
al;
close
an
d lo
ck
the
positiv
e-lockin
g
loadin
g tr
ay.
17.
Rec
ord
DVM
whe
n C
arbo
n in
dic
ato
r tu
rns
gree
n.
18.
Aft
er
both
C
arbo
n an
d A
naly
ze
are
gr
een,
de
pres
s A
na
lyze
. W
hole
cy
cle
re
pe
ats
on
th
e
seco
nd
bla
nk.
19.
Pro
ceed
w
ith
bla
nks
u
ntil
two
in
a ro
w r
ead
ap
pro
xim
ate
ly £
0.0
07
.
20.
Nex
t bu
rn
a 0.
350
pe
rce
nt
sta
nd
ard
in
th
e
abov
e m
anne
r.
DVM
sho
uld
re
ad
±1
perc
ent
of
C va
lue
o
r ±
0.00
2 perc
ent
C,
whic
heve
r is
gre
ate
r.
(To
lera
nce
is
on
th
e r
ing
standard
b
ott
le).
21.
If
readin
g is
no
t w
ith
in
tole
ran
ce
, ru
n anoth
er
as
abov
e.
Not
e DV
M re
ad
ing
.
22.
If
step
21
is
not
with
in
tole
rance,
run
anoth
er
standard
. W
hen
Car
bon
lig
ht
turn
s gre
en,
unlo
ck
and
ad
just
H
igh
Perc
ent
Car
bon
co
ntr
ol
un
til
DVM
is
within
to
lera
nce
.
23.
Run
one
mor
e st
andard
to
be
su
re
DVM
is
repeate
d.
24.
Now
pre
pa
re
and
run
a se
ries
of
a bla
nk
plu
s st
an
da
rds
in
the
O
pera
te p
ositio
n.
If all
is w
ell,
pr
ocee
d w
ith
unkn
owns
, ru
nn
ing
th
e
sam
e se
rie
s o
f st
an
da
rds
at
the
end
of
the
sam
ple
run.
Dur
ing
each
ru
n,
wat
ch
the
pla
te
cu
rre
nt
met
er
on
the
fu
rna
ce.
It
shou
ld re
gis
ter
>500
ma.
V
isu
ally
ch
eck
each
sa
mpl
e fo
r co
mpl
ete
com
bu
stio
n.
If
the
met
er
neve
r re
ache
s 50
0 m
a,
wei
gh
a sm
alle
r p
ort
ion
of
the
sam
ple.
R
un
3 rin
g
standard
s fo
r a
4 pt.
calib
ration
curv
e.
If
standard
va
lue
s fa
ll
off,
lan
ce
mig
ht
be
clo
gg
ed
.
25.
At
the
end
of
the
sequ
ence
(s
tandard
s-sa
mple
s-st
andard
s),
depr
ess
Sta
ndby
sw
itch.
26.
Tur
n o
ff:
Hig
h vo
ltag
e,
Fila
me
nt
volta
ge
, B
lank
S
witc
h,
and
Oxy
gen
Tan
k.
27.
Aft
er
oxyg
en
blee
ds
dow
n,
depr
ess
Q£
switc
h
(lig
ht
no
t glo
win
g).
28.
Tur
n F
un
ctio
n
sele
ction
switc
h
to
Pre
-Am
p ze
ro.
Set
R
ange
to
hig
h
scale
.
29.
Dus
t tr
ap
and
com
bust
ion
tube
area
m
ust
be
clea
ned
aft
er
20-2
5 sa
mpl
es.
Sam
ple
entr
ain
ed
Mag
nesi
um P
erc
hlo
rate
m
ust
be
chan
ged
eve
ry 4
ho
urs
of
sam
ple
usag
e.
For
g
en
era
l m
ain
tenance
, se
e p.
7-
1 of
instr
uctio
n
man
ual2
.10
4
30.
Ave
rage
th
e
DVM
resu
lts
of
the
standard
rings
and
pe
rfo
rm
a lin
ea
r re
gre
ssio
n
of
the
data
. S
tand
ard
rings
are
assu
med
to
be
1
gram
ea
ch.
31.
Car
bon
Ran
ge
switc
h
shou
ld
be
on
0.0
05
0-0
.10
00
perc
ent
C p
ositio
n.
32.
Aft
er
appro
xim
ate
ly
30
seco
nds,
de
pres
s th
e
gree
n A
naly
ze sw
itch.
33.
Car
bon
lig
ht
will
eve
ntu
ally
tu
rn
wh
ite
and
Ana
lyze
lig
ht
will
turn
g
ree
n.
Whe
n A
naly
ze lig
ht
turn
s o
ff,
rem
ove
cru
cib
le.
Load
a
no
the
r bla
nk
imm
edia
tely
.
34.
Whe
n C
arbo
n lig
ht
turn
s g
ree
n,
reco
rd
DVM
. DV
M
shou
ld
no
t be
>
0.00
10
pe
rce
nt
C.
35.
Dep
ress
B
lank
sw
itch
(g
low
s w
hite
).
36.
Unl
ock
the
B
lank
A
dju
st
Co
ntr
ol
(while
C
arbo
n is
still
gree
n)
and
ad
just
to
0.00
0 on
DV
M.
37.
Onl
y w
hen
both
C
arbo
n an
d A
naly
ze
are
gree
n,
depr
ess
Analy
ze.
Sec
ond
bla
nk
shou
ld
read
<
0.00
10.
If it
does
n
ot,
a
dju
st
as
in
step
36.
38.
Bur
n a
ring
standard
of
appro
xim
ate
ly
0.17
0 p
erc
en
t C
. R
eadi
ng m
ust
be w
ithin
to
lera
nce
th
at
is
state
d
on
the
Rin
g st
andard
b
ott
le
(+ o
r -
1 perc
ent
of
C va
lue
).
If
no
t,
ad
just
Lo
w
pe
rce
nt
C contr
ol
wh
ile
carb
on lig
ht
is
white
.
39.
Rep
eat
0.17
0 ring
sta
nd
ard
u
ntil
acc
ep
tab
le
DVM
rea
din
g
is
ob
tain
ed
; a
dju
st
as
nece
ssary
.
40.
Rep
eat
a b
lan
k an
d a
dju
st
Bla
nk
Ad
just
if
nece
ssary
; if
adju
sted,
the
0.1
70
rin
g
mus
t be
bu
rned
an
d ch
ecke
d.
41.
Che
ck
back
an
d fo
rth
be
twee
n lo
w
and
hig
h u
ntil
no
ad
just
me
nt
is
nece
ssary
.
42.
Pro
ceed
d
ire
ctly
to
No.
24
ab
ove
and
con
tinu
e
thro
ug
h
No.
30
.
Com
pile
d by
P.
Klo
ck10
5
REF
EREN
CES
1.
Leco
C
orp
ora
tion,
St.
Jo
seph
, M
I.,
WR
-12
Instr
uctio
n
Man
ual.
2.
Leco
C
orp
ora
tion
, S
t.
Jose
ph,
MI.,
Induct
ion
Fur
nace
(m
odel
76
3-20
0)
Instr
uctio
n
Man
ual.
3.
Till
man,
John
H
. 19
77,
A C
om
bu
stim
etr
ie
Met
hod
for
Dete
rmin
ing
the
Tota
l C
arbo
n C
onte
nt of
Geo
logi
c M
ate
ria
ls:
Jou
rna
l R
esea
rch
U.S
. G
eol.
Sur
vey,
v.
5
, no
. 5
, p.
58
3-58
7.
106
TABL
E 1
Gen
eral
cla
ssific
ation o
f so
me
geolo
gic
m
ate
ria
ls
for
tota
l ca
rbon
d
ete
rmin
atio
nusi
ng th
e
WR
-12
carb
on
dete
rmin
ato
r
Ma
teria
l
Basa
lts,
horn
ble
nde,
dio
rite
Hornblendes,
rhyo
lite
s,
andesites,
peri
dotite,
granites,
gnei
ss,
diabase,
basa
lt
Gran
odio
rite
, syenites,
gabbro,
granites
Sulf
ides
, phyllites,
syen
i te
s
Mari
ne se
dime
nts,
phosphate
rocks,
clay
s,tu
ff,
1ime
ston
es
Percent
total
C
0.005-0.010
.010
-0.2
00
.100-0.500
.500-1.00
>1.0
0
Samp
le Wt
.
0.75
-1.0
.50-1.0
.100
-0.5
.100-0.5
.100-0.5
Type
Acce
lera
tor
Fe/Cu
Fe/Cu
Fe/Cu
Fe/Cu
Fe/Cu
107
POW
DER
DE
NS
ITY
O
F R
OC
KS
(Con
dens
ed
from
L.
S
ha
piro
, US
GS P
rof.
Pap
er
650-
B)
Fin
ely
cr
ushe
d ro
ck
<£ 8
0 m
esh)
si
nks
or
flo
ats
in
a
heav
y liquid
, if
not
ag
ita
ted
, as
la
rge
aggr
egat
es
of
the
constitu
ent
min
era
ls r
ath
er
than
as
dis
crete
g
rain
s.
The
aver
age
de
nsi
ty o
f th
e cl
umpe
d,
crus
hed
mate
rial
clo
se
ly
appr
oxim
ates
th
at
of
the r
ock
po
wde
r an
d m
ay b
e de
term
ined
by
a
sim
ple
sin
k-f
loat
tech
niq
ue.
Sm
all
sam
ples
o
f po
wde
red
rock
ar
e ce
ntr
ifuged
in h
eavy
liq
uid
s
in
a se
quen
ce
desi
gned
to
b
rack
et
the
ir
de
nsitie
s w
ith
in
narr
ow
lim
its.
Onl
y ~1
00 m
g o
f sa
mpl
e is
re
qu
ire
d
to
obta
in
a densi
ty d
ete
rmin
atio
n
within
±
0.0
4
Rea
gent
s (a
ll ch
em
icals
-reagent
gra
de):
Pro
cedu
re
Fre
shly
p
rep
are
eig
ht
heavy-liq
uid
mix
ture
s acc
ord
ing t
o
the
pro
po
rtio
ns
give
n in
T
ab
le
1.
Met
hyle
ne
iod
ide
m
ixtu
res
store
d
in
ambe
r bottle
s
con
tain
ing
a
smal
l pie
ce of
copp
er
wire
m
inim
izes
light-
induced
deco
mposi
tion
and
the
altera
tion
of
the
d
en
sity
by
iod
ine
re
lea
se
.
Liq
uid
d
esi
gn
atio
n
Bottle
s
Tab
le
1.
Prim
ary
M
ixtu
res
Car
bon
Te
tr a
chlo
ride
(Sp.
gr.
1.5
9)
25 20 14.3 8.3
2
ml.
Bro
mof
orm
(S
p.
gr.
2.8
9)
Met
hyle
nelo
di d
e (S
p.
gr.
3.3
2)
Resu
ltant
Sp
eci
fic G
ravity
22 29 35 43,
50 33,
20
5 m
l.
7 7
11.5
m
l.33
.350
20 36 52 68 84 00 163.
32
108
2.
To
fam
iliarize .y
ours
elf
with
th
e m
etho
d,
run
two
or
thre
e
standard
s (i.e
. W
-l an
d S
ierr
a Q
uart
z;
de
nsitie
s
3.0
0
and
2.64
re
sp
ective
ly).
3.
With
a
smal
l sp
atu
la,
tra
nsfe
r 40
-50
mg
of
pre
-mix
ed
sam
ple
(<80
mes
h) to
tw
o 10
ml
con
ica
l ce
ntr
ifu
ge
tu
be
s.
Usu
ally
ea
ch
sam
ple
requires
fou
r (4
) tu
be
s.
4.
Add
0.3
m
l of
liqu
id
D to
on
e o
f th
em.
Do
no
t a
gita
te,
bu
t ce
ntr
ifu
ge
fo
r on
e m
inut
e an
d ex
amin
e.
5.
Cla
ssify
the r
esu
lts
as
follo
ws:
a.
The
en
tire
sam
ple
floats
, or
b.
The
en
tire
sa
mpl
e sin
ks,
orc.
Th
e sa
mpl
e splits
to
fo
rm o
ne
laye
r on
to
p
and
one
laye
r on
b
ott
om
, or
d.
The
sam
ple
is
dis
pers
ed
thro
ug
ho
ut
the liq
uid
in
w
hich
ca
se it
has
the
sa
me
de
nsity
as
liquid
D
.
Whe
n ca
teg
orizin
g,
ignore
appro
xim
ate
ly 5
perc
ent
or
less
w
hich
m
ay
go
in
the d
ire
ctio
n
opposi
te
to
that
of
the
bu
lk
of
the
sa
mpl
e.
6.
If
(a)
occ
urs
, ad
d 0.3
m
l liq
uid
C
to
the
se
cond
tu
be
.If
(b
) occ
urs
, ad
d 0.
3 m
l liq
uid
E
inst
ea
d
to
the
seco
nd
tub
e.
If
(c)
occ
urs
, ad
d 0
.3 m
l liq
uid
C to
th
e
seco
nd
tub
e,
and
add
0.3
m
l liq
uid
E
to
a th
ird
tu
be
to
whi
ch
has
been
adde
d an
othe
r port
ion of
sam
ple.
7.
Centr
ifuge
the
tube
s fo
r on
e m
inut
e an
d ca
teg
orize
as
in
st
ep 5
.
8.
If n
ece
ssa
ry,
rep
ea
t w
ith
ad
ditio
na
l port
ions
of
sam
ple
until
two
adjo
inin
g liq
uid
s
in
table
1
are
foun
d in
w
hich
th
e sa
mpl
e flo
ats
in
on
e an
d si
nks
in
th
e n
ext
.
9.
Whe
n th
e
two
ad
join
ing
liq
uid
s
are
loca
ted,
pour
th
e
conte
nts
of
the
tw
o tu
bes
back
an
d fo
rth
to
m
ix t
hem
p
rod
uci
ng
a
liq
uid
of
inte
rme
dia
te
density,
e.g
. D
E,
who
se specific
g
ravity o
r d
en
sity
is
2
.76
. C
en
trifu
ge
fo
r on
e m
inute
an
d ca
teg
orize
.
109
For
exa
mple
, deci
de
upon
th
e
density
as
follo
ws:
______________If
The
Sam
ple
:______________
dis
pers
es
or
floats
in
: si
nks
in
: T
he re
su
lta
nt
sp
lits
in
: density is
;
D E
C .
2.6
8CD
D
C 2.
60CD
2
.64
CD
2.5
6
If
a sa
mpl
e fo
rms
two
dis
cre
te
laye
rs
in
two
ad
join
ing
prim
ary
mix
ture
s,
or
if it sin
ks
in
the
heavie
st
liq
uid
, th
e
density
cannot
be
dete
rmin
ed
by th
is
met
hod.
REFE
RENC
ES
1.
Shapiro,
L.,
1975
, R
apid
a
na
lysi
s of
silic
ate
, ca
rbo
na
te,
and
phos
phat
e ro
cks,
revis
ed
e
ditio
n,
USGS
B
ulletin
1401
, p
. 71
.
2.
Shapiro,
L.,
19
69
, R
apid
dete
rmin
atio
n
of
pow
der
de
nsity of
rock
s by
a
sin
k-f
loat
tech
niq
ue
, US
GS
Pro
f.
Pap
er
65
0-B
, p
. 140-1
42.
Com
pile
d b
y P
. K
lock
an
d M
. C
rem
er
110
DIG
ES
TIO
N
MET
HO
D
FOR
FLU
OR
INE
IN
S
ILIC
AT
ES
(Ada
pted
fr
om
De
term
ina
tion
o
f F
luo
rid
e
in
Sili
cate
R
ocks
W
itho
ut
Se
pa
ratio
n
of
Alu
min
um
Usi
ng
a S
pe
cific
Io
n E
lect
rode,
Bla
nche
L.
In
gram
, A
nal.
Che
m.,
v.
42,
no.
14,
Dec
. 19
70)
Sam
ples
ar
e sin
tere
d w
ith
sodi
um
carb
onate
an
d zi
nc
oxi
de
, th
en
dig
est
ed
ove
rnig
ht
at
stea
m-b
ath
tem
pera
ture
. Th
e re
sidue
is
filtere
d o
ff
and
is
reje
cte
d.
Nitric
aci
d
is
adde
d to
th
e filtra
te
whi
ch
is
mad
e to
vo
lum
e w
ith
wate
r.
Equ
al
aliq
uo
ts
of
filtra
te
and
bu
ffe
r ar
e m
ixed
, an
d th
e p
ote
ntia
l o
f th
e so
lutio
n
is
mea
sure
d w
ith
a specific
io
n ele
ctr
ode.
Sta
ndar
ds
are
prep
ared
fr
om
a so
dium
flu
orid
e
solu
tion
and
are
m
atch
ed
to
the
sam
ples
w
ith
sodi
um
carb
on
ate
an
d nitric a
cid
. A
plo
t o
f th
e
log of
the
flu
orid
e
conce
ntr
atio
n
as
ord
inate
an
d EM
F as
a
bci
ssa
pr
oduc
es
curv
e lin
ea
r to
appro
xim
ate
ly
0.4
pp
m w
ith
a n
eg
ativ
e
slo
pe
.
Rea
gent
s (a
ll ch
em
icals
-reagent
gra
de):
0.2
M
sodi
um citra
te -
0.2
M
pota
ssiu
m nitra
te
solu
tion.
Dis
solv
e
59
gram
s o
f so
dium
citra
te
dih
ydra
te
and
20
gram
s of
pota
ssiu
m n
itra
te
in
wate
r.
Dilu
te
to
one
lite
r.
Sta
ndar
d flu
orid
e so
lutio
n.
Hea
t Na
F in
a
pla
tinum
cru
cib
le
at
low
re
d
heat
(640
°C)
for
1-2
hours
. C
oo
l, w
eigh
1.
105
gram
s,
dis
solv
e
in
wa
ter,
an
d d
ilute
to
50
0 m
l. T
ransf
er
to
a p
oly
eth
yle
ne
bo
ttle
fo
r st
ora
ge.
1 m
l =
1000
yg
flu
orid
e.
Pro
cedu
re
1.
Wei
gh
a 10
0 m
g sa
mpl
e in
a
smal
l pla
tinum
cru
cib
le.
Mix
with
0.
5 g
of
anhy
drou
s so
dium
ca
rbonate
an
d 0.
1 g
of
zin
c oxi
de.
2.
Sin
ter
at
900°
C fo
r 30
min
ute
s.
Pla
ce
the
cool
ed
cru
cib
le
in
a g
lass
beake
r,
add
30 m
l of
H20
, co
ver
the
b
ea
ker,
an
d dig
est
on
th
e
stea
m b
ath
ove
rnig
ht.
3.
Rem
ove
the cru
cib
le,
catc
h
rinse
s in
b
ea
ker,
br
eak
up
any
lum
ps,
and
allo
w
the
so
lutio
n
to
cool
to
roo
m
tem
pera
ture
.
4.
Use
W
hatm
an
No.
42
filter
pape
r to
filter
the so
lutio
n
into
a
100
ml
volu
me
tric
fla
sk.
Was
h th
e re
sidue
seve
ral
times
w
ith
smal
l port
ions
of
0.1
pe
rce
nt
sodi
um
carb
on
ate
so
lutio
n.
Re
ject
th
e r
esi
due.
Com
men
ts
1.Z
inc
oxi
de
is
ad
ded
to
pro
vid
e
a m
ore
gra
iny
resi
due
whi
ch
tra
ps
mor
e silic
on.
4.
Ch
lorin
e
is
retu
rne
d
and
foun
d in
th
e filtra
te.
It
may
be
dete
rmin
ed co
lorim
etr
ica
lly.
See
proc
edur
e fo
r co
lorim
etr
ic ch
lorin
e.
Ill
5.
Slo
wly
ad
d 1.5
m
l 1
+ 1
nitric
aci
d
to
the
so
lutio
n,
shaki
ng vig
oro
usly
to
ex
pel
CO
?.
Dilu
te
to
volu
me
with
wa
ter.
M
ix w
ell.
6.
Pre
pa
re
a se
ries
of
Sta
ndar
ds
as
follo
ws:
To
a 50
0 m
l vo
lum
etr
ic
fla
sk,
add
2.5
0
gra
ins
sodi
um
carb
onate
. Ad
d w
ate
r to
d
isso
lve
. C
are
fully
ad
d to
th
e fla
sk
7.5
m
l o
f 1
+ 1
HN
03.
Dis
pel
as
muc
h C
02
as
po
ssib
le
by sh
aki
ng
. M
ake
to
volu
me
with
H20
. M
ix.
To
a se
ries
of
five
10
0-m
l vo
lum
etr
ic fla
sks,
add
0.4
m
l an
d 0
.8
ml
of
100
ppm
F
- solu
tion;
0.2
m
l, 0
.4
m.,
and
0.8
m
l of
1000
pp
m
F~
solu
tion
resp
ective
ly.
Mak
e to
vo
lum
e w
ith
the
pre
vio
usly
pr
epar
ed
NaC
03 -
HN
03 so
lutio
n.
7.
Be
gin
nin
g w
ith
the
low
est
st
andard
, i.e
. 0.
4 pp
m,
pip
ette
5.0
ml
of
the
solu
tion
into
a
smal
l p
lastic
cap.
Ad
d 5
.0 m
l o
f th
e
sodi
um citra
te-p
ota
ssiu
m
nitra
te solu
tion.
Mix
w
ell.
Im
mer
se
the
ele
ctro
de
s in
th
e solu
tion.
Co
ntin
ue
sl
ow m
ixin
g.
Rea
d an
d re
cord
th
e p
ote
ntia
l after
5 m
inute
s.
In
the
sam
e m
anne
r,
dete
rmin
e th
e
pote
ntial
of
the
rem
ain
ing
standard
s as
w
ell
as
that
of
the
sa
mpl
e so
lutio
ns.
8.
Tre
atin
g m
illivolts
as
the
inde
pend
ent
variable
an
d th
e
log
of
the
con
cen
tra
tion
s as
th
e
depe
nden
t va
ria
ble
, pre
pare
an
equatio
n
by
the
met
hod
of
lea
st
square
s.
Use
th
e
equatio
n
to
calc
ula
te
the
conce
ntr
atio
ns
of
the
kn
owns
. R
epor
t in
p
erc
en
t F~
to
tw
o de
cim
al
pla
ces.
It
is
ext
rem
ely
d
ifficu
lt
to
expe
l all
the
C02
-M
uch
care
m
ust
be
take
n a
fte
r dilution
to
volu
me.
Th
evo
lum
etr
ic
sto
pp
er
shou
ld
be
rele
ase
d periodic
ally
.
The
proc
edur
e pro
vides
for
a se
ries
of
0.4
, 0
.8,
2,
4,
and
8 pp
m
F~
standard
s,
to
be
used
fo
r a
ca
libra
tio
n
curv
e.
Thes
e st
andard
s ca
n be
us
ed
ove
r a
period of
seve
ral
wee
ks.
7.
Pot
assi
um n
itra
te
is
used
in
th
e citra
te
solu
tion
to
pre
ven
t ele
ctro
de
fatig
ue
. Th
e pH
of
the
sa
mpl
e solu
tions
aft
er
dilu
tio
n
with
th
e citra
te-n
itra
te
solu
tion
is
~6
.3.
With
th
is
solu
tion,
alum
inum
do
es
no
t in
terf
ere
a
t th
e
28 perc
ent
A12
03
leve
l in
so
lutio
ns
with
0.0
04
to
0.0
8
perc
ent
F~.
If
mor
e th
an
0.0
8 p
erc
en
t F~
is
p
rese
nt,
as
m
uch
as
38
pe
rce
nt
A12
03
does
n
ot
inte
rfe
re.
8.
A le
ss
rigoro
us
met
hod
may
be
used
by
p
lott
ing
th
e
data
on
se
mi-lo
g
pape
r an
d re
ad
ing
th
e
unkn
own
conce
ntr
atio
ns
fro
m
the
grap
h. Com
pile
d by
M
. C
rem
er
112
REF
EREN
CES
1.
Ingr
am,
B.
L.,
19
70,
De
term
ina
tion
o
f fluoride
in silic
ate
ro
cks
with
ou
t se
pa
ratio
n o
f al
umin
um
usi
ng
a
specific
io
n e
lect
rod
e:
An
al.
Che
m.,
v.
42,
no.
14,
p.
1825
-182
7.
2.
Orio
n In
str
uctio
n
Man
ual
flu
orid
e
ele
ctro
de
s m
odel
94-0
9,
mod
el
96-0
9,
1977
.
113
STANDARD A
DDIT
ION
METH
OD FOR
FLUO
RINE
IN
SILICATES
(Ada
pted
from D
eter
mina
tion
of
Fluorine in Si
lica
tes
by Use
of an Ion-selective
Elec
trod
e Following
Fusi
on w
ith
Lithium
Metaborate,
J. B. Bodkin,
The
Analyst, v. 102, no
. 12
15)
Samples
are
fused
with lithium
meta
bora
te an
d di
ssol
ved
in ni
tric
acid.
A complexing b
uffe
r is
added, an
d the
potential
of t
he s
olution
is determined w
ith
a pH
met
er w
ith
a ab
solu
te m
illivolt scale.
A known
volume of
standard
fluo
ride
solution is added; the
potential
is again
chec
ked;
and
the
concentration
of fluoride in th
e sample is
computed us
ing
the
pote
ntia
l difference an
d th
e Nernst e
quation.
Samp
les
containing as
much
as 2.7
perc
ent
fluo
rine
may
be analyzed.
Reag
ents
(a
ll chemicals-reagent
grad
e):
Lith
ium
metaborate.
Anhy
drou
s Li
Nitric acid,
2.56
percent
v/v,
ar
rang
ed f
or delivery f
rom
a 50 m
l teflon stopcock type au
toma
tic
pipe
t.
Standard f
luoride
solution.
Heat
NaF
in
a' pl
atin
um c
rucible
at low
red
heat (6
40°C
) for
1-2
hour
s.
Cool
, we
igh
1.10
5 gr
am,
dissolve in H
20 a
nd d
ilut
e to
500 m
l.
Transfer to
a
poly
ethy
lene
bottle
for
stor
age.
1
ml =
1,00
0 yg
fl
uori
de.
Comp
lexi
ng b
uffer
solution.
Add
18.2 g
of DCTA (l,2-diaminocyclohexane-NNN'N'-tetraacetic ac
id),
also known
as DCYTA
(1,2
-cyc
lohe
xyle
nedi
nitr
ilo-
tetr
acet
ic ac
id)
to 1.
5 li
ter
of H2
0 and
then
40 p
ercent m
/v NaOH so
luti
on dr
opwi
se
unti
l th
e DC
TA d
issolves.
Add
300
g so
dium
citrate d
ihydrate an
d 60
g Na
Cl,
adju
st th
e pH t
o 6.85 w
ith
HC1
and
dilute to 2
li
ter
with
H20.
Arra
nge
for
delivery f
rom
a 50
ml
teflon stopcock-type
automatic
pipet.
Proc
edur
e
1. Mi
x 80
mg
sample w
ith
320
mg L
iB02
. Tr
ansf
er th
e mi
xtur
e to a
graphite cr
ucib
le an
d fuse in a mu
ffle
fu
rnac
e at 1050°C fo
r 10
minutes.
At th
e same time,
fuse a
blan
k an
d a
stan
dard
roc
k in
the
same m
anne
r.
Carr
y them,
together w
ith
the
sample,
thro
ugh
the
proc
edur
e.
2. Wh
ile
the
sample is fusing,
add
to a
4 1/
2 oz
(1
10 m
l)
poly
prop
ylen
e container
(Falcon),
a magnetic st
irri
ng
bar
and
50 m
l of 2
.56
percent
HN03
with
the
automatic
pipe
t.
Comm
ents
1. At
th
is te
mper
atur
e, some e
lements
are
not
quan
tita
tive
ly r
etained; e.
g.,
the
alka
lis,
chlorine,
and
sulf
ur.
2. Th
e containers m
ust
be la
rge
enough to
ac
como
date
100
ml pl
us th
e subsequent ad
diti
on.
114
3. Begin
stir
ring
the
solution m
agne
tica
lly
as the
fusi
on
nears
comp
leti
on.
Remove th
e cruc
ible
fr
om t
he
muffle,
swirl
it,
and
then pour the
molt
en bead in
to
the
containe
r.
4. Cover
the
cont
aine
r an
d continue stirring u
ntil th
e sample is
di
ssol
ved
usua
lly
abou
t 15
minutes.
5. Wh
en so
luti
on is
complete,
add
50 m
l of
buf
fer
from
the
auto
mati
c pipet.
Stir
well.
Cove
r.
Set
asid
e.
3. Swirling t
he h
ot c
ruci
ble
insures
more
com
plet
e co
ales
cenc
e of t
he m
olten
subs
tanc
e.
5. DC
TA b
uffe
rs t
he solution to
a
pH o
f approximately
5.5.
At
a
pH b
elow 5
, hydrogen co
mple
xes
fluoride as
the
undissociated
acid HF an
d the
ion
HF2«
At a
pH >7
, hy
drox
ide
ion
interferes when the
leve
l of
hydroxide
is gr
eate
r than 1/10 t
he level
of fluoride
ion
pres
ent.
DC
TA c
ontrols
Al and
Fe in
terf
eren
ce.
6. Fr
om th
e standard Na
F solution prepare
10 a
nd 100
ppm
fluoride so
luti
ons.
7. Use
the
blank
solution to pr
epar
e a
cali
brat
ion
curve
as follows:
Add
0.2
ml of 10 p
pm Na
F solution to
the
blank,
stir and
immerse
the
electrodes in th
e st
irri
ng
solu
tion
. When a constant po
tent
ial
read
ing
is
obtained (u
sual
ly 5
minutes), record th
e millivolts.
Cont
inue
in
the
same
man
ner
with th
e ad
diti
on to
the
same solution o
f th
e following
increments:
0.5
ml
0.8
ml
0.2
ml
0.5
ml
0.8
ml
0.2
ml
0.5
ml
0.8
ml
of 1
0 ppm
of 10
ppm
of 1
00 p
pm
of 10
0 ppm
of 1
00 p
pm
of 1000 p
pm
of 1
000
ppm
of 1000 p
pm
6. These
solutions
are
used
to p
repare a
cali
brat
ion
curv
e as we
ll as to ad
d increments to
the
samp
le
solu
tion
s.
7. Th
e accumulated
concentrations in
yg/ml
are
0.02
, 0.
07,
0.15
, 0.34,
0.83
, 1.60,
3.54
, 8.34,
and
15.93,
The
very small
volume changes
do n
ot af
fect
the
sign
ific
ant
figures
shown.
115
8. Using
semi-log paper, pl
ot th
e concentration
in pp
m on
the
vert
ical
or lo
g ax
is and
the
mv readings on the
horizontal axis.
Draw a
st
raig
ht li
ne from t
he
high
est
concentration
to 0.
15 ppm.
Dete
rmin
e the
slop
e by s
ubtracting m
illi
volt
read
ings
a
deca
de apart
in co
ncen
tration.
9. Im
mers
e th
e el
ectr
odes
in th
e sample solution,
stir
ring
-as
befo
re.
Reco
rd t
he m
illivolt re
adin
g after
5 minutes.
10.
Use
the
foregoing
read
ing
with the
graph
to determine
the
apparent concentration
in ppm
of the
unkn
own.
Ap
prox
imat
ely
double the
appa
rent
co
ncen
trat
ion;
add
that
am
ount
of standard fl
uori
de to the
solution,
stir
, and
again
reco
rd t
he p
otential after
5 mi
nute
s.
This procedure
should le
ad to
a
A£ o
f -1
5-30
mV.
8. The
graph
is to
be
used to r
ead
an approximate
concentration
of t
he un
know
n wh
ich
must be
at le
ast
doubled
when
the
addition is made to t
he un
know
n.
The
theoretical
slope
vari
es with temperature, but
betw
een
20 a
nd 25
°C,
it is
approximately
58 m
v fo
r a
univ
alen
t el
ectrode.
The
slope
must be
ch
ecke
d ea
ch
time
fl
uori
ne is determined.
Only
two
so
luti
ons
a decade ap
art
in c
once
ntra
tion
are
prep
ared
and
the
potentials de
term
ined
.
10.
If an
un
cert
aint
y of -
0.5
mV in
AE an
d -1
.0 m
V in
slope
is as
sume
d, a minimum
erro
r re
sult
s at a
A£ o
f ap
prox
imat
ely
15-3
0 mV.
116
11.
Calc
ula
te
the
exac
t co
nce
ntr
atio
n
of
the in
itia
l so
lutio
n
usin
g th
e fo
llow
ing
form
of
the
Ner
nst
equatio
n:
C=C
* [(
Vs/
(Vx
+ V
s)]
__________
(antilo
g
AE
/S)-
[Vx/
(Vx
+ V
s)]
C=S
ampl
e co
nce
ntr
atio
nC*
Conce
ntr
atio
n
of
additi
on
befo
re
addi
ngto
sa
mpl
e V
x=S
ampl
e vo
lum
e V
s=vo
lum
e of
ad
diti
on
A
E=
pote
ntia
l diff
ere
nce
bet
wee
n in
itia
l an
dfin
al
millivolt
valu
es
with
additi
on
of
standard
. S
=*n
illiv
olt
span
o
f e
lect
rod
e
for
deca
deo
f in
tere
st;
i.e.,
the
slope.
The
units
o
f C
are
ng/m
l. T
he
refo
re,
Per
cent
F
=
[yg/
ml
(i.e
. Q
] (1
00 m
l)
(100
p
erc
en
t)
(100
0 ng
/mg)
(w
t.
in m
g)
Rep
ort
the v
alue
s to
tw
o de
cim
al
pla
ces.
A
com
pute
r pr
ogra
m is
a
vaila
ble
fo
r th
e ab
ove
calc
ula
tions
on
both
th
e T
ekt
ronix
40
51
and
the
HP
-97.
12.
Whe
n mv
re
adin
gs
appr
oach
ze
ro o
r cr
oss
to
the
ne
ga
tive
a
xis
, m
ake
anot
her
fusi
on
in
th
e us
ual
man
ner.
Add
an
aliq
uot
of
the
solu
tion
to
an
othe
r be
aker
an
d d
ilute
with
an
aliq
uot
of
aci
d
to
50 m
l. C
ontin
ue w
ith
the
de
term
ina
tion
as
usu
al.
The
calc
ula
tions
are
alte
red
by co
nsi
de
rin
g t
he s
ampl
e w
eig
ht
in
mg
pres
ent
in
the
aliq
uo
t,
Com
pile
d by
M
. C
rem
er
117
REFERENCES
1.
Beck
man
Scie
ntif
ic In
stru
ment
s Di
visi
on P
rodu
ct Da
ta Sh
eet
EC-8148, Standard Ad
diti
on Nomograph
for
use
with
Beck
man
Selection
Electrodes.
2.
Bodk
in,
J. B.,
1977,
Dete
rmin
atio
n of
flu
orin
e in siliates by
use of
an
ion-selective
electrode
following
fusi
on
with li
thiu
m me
tabo
late
: The
Anal
yst,
v. 102, no.
1215,
p. 40
9-41
3.
3.
Orio
n Instruction
Manu
al fl
uori
de el
ectr
odes
model
94-0
9, model
96-0
9, 19
77.
118
DIGE
STIO
N ME
THOD
FOR
FLUO
RINE
IN PHOSPHATE
(Ada
pted
fr
om
De
term
inin
g
Flu
orid
e
in
Roc
ks
with
a
Sp
ecific
Io
n E
lect
rode,
Bla
nche
L.
In
gram
and
Ir
vin
g
May
, U
.S.
Ge
olo
gic
al
Sur
vey
Pro
fess
ion
al
Pap
er
750-
B,
p.
B18
0-B
184)
The
phos
phat
e ro
ck
sam
ple
is
deco
mpo
sed
by
dig
est
ion
in d
ilute
n
itric
aci
d.
The
so
lutio
n
is filtere
d;
the
re
sidue
is
was
hed
with
1
perc
ent
HN
03;
and
the
re
su
ltin
g f
iltr
ate
is
m
ade
to
volu
me
with
w
ate
r.
An
aliq
uo
t is
tr
an
sfe
rre
d
to
anot
her
volu
me
tric
flask,
a so
dium
citra
te-p
ota
ssiu
m n
itra
te solu
tion
is
adde
d,
and
the
com
bin
atio
n
mad
e to
vo
lum
e w
ith
wate
r.
Sta
ndar
d flu
orid
e
so
lutio
ns
conta
inin
g th
e
sam
e buffer
are
prep
ared
fo
r a
ca
libra
tio
n
curv
e.
Flu
oride
in all
solu
tions
is
mea
sure
d w
ith
a specific
io
n ele
ctro
de.
Rea
gent
s (a
ll
che
mic
als
-re
ag
en
t g
rad
e):
0.6
M so
dium
citra
te
dih
ydra
te -
0.2
M
pota
ssiu
m n
itra
te
solu
tion.
Dis
solv
e
177
g o
f so
dium
citra
te
dih
ydra
te
and
20
g KN
03
in
wat
er
and
dilu
te
to
one
lite
r.
0.3
M
sodi
um citra
te -
0.1
M
pota
ssiu
m nitra
te
solu
tion.
Dis
solv
e
88.5
g
of
sodi
um citra
te
dih
ydra
te
and
10
g KN
03
in
wate
r;
add
2.5
ml
I +
1 H
N03
an
d d
ilute
to
1
lite
r.
Sta
ndar
d fluoride so
lutio
ns.
Pre
pare
st
an
da
rds
con
tain
ing
0.4
, 0
.6,
1,
2,
3,
and
4 pp
m
F fr
om
10
00 p
pm st
ock
st
andard
F
so
lutio
n
usi
ng
th
e 0
.3 M
so
dium
citra
te -
0.1
M
pota
ssiu
m nitra
te
so
lutio
n
as d
ilu
ten
t.
Bef
ore
mak
ing
to
volu
me,
ad
d 1+
1 HN
03
to
mat
ch
the
unkn
owns
; e
.g.
if
100
ml
flasks
are
used
, ad
d ~
0.3
m
l to
ea
ch
flask.
Pro
cedu
re
1.
Digest 1
00 m
g sample w
ith
5 ml
of 1
+
1 HN
03 f
or a
few
minu
tes
on the
stea
m ba
th to
de
comp
ose
the
samp
le
2.
Filter th
e so
luti
on into a
100
ml vo
lume
tric
fl
ask.
Wash th
e paper
and
resi
due
with 1
perc
ent
HN03.
Dilute to v
olume
with wa
ter.
Mi
x we
ll.
3.
Transfer a
5 ml aliquot
of t
he s
ample
solu
tion
to
a
100
ml volumetric fl
ask.
Add
50 m
l of
0.6
M
sodium c
itrate - 0.2
M KN03
solution an
d dilute to v
olum
e with w
ater.
Mix
well
Comments
Generally, fluorine in phosphate
equals ap
prox
imat
ely
0.1
the
phosphorus concentration.
Ther
efor
e, this
aliquot
prov
ides
ad
equa
te fluorine 0.4 to 4
.0 p
pm.
This
provides a
sample s
olut
ion
in 0.
3 M
sodium
citrate
- 0.1
M KN03 m
edium
to m
atch the
standards.
Aluminum in
terference is co
ntro
lled
by
the
citr
ate. 119
5.
Sta
rtin
g w
ith
the
lo
west
st
an
da
rd
and
pro
cee
din
g t
o
5.
The
se
lective
io
n
ele
ctro
de
su
ffe
rs
fro
m m
emor
yhig
her
con
cen
tra
tion
s,
mea
sure
th
e
solu
tion
po
ten
tia
ls
eff
ects
. T
here
fore
, if
a dilu
te solu
tion
is
mea
sure
d as
fo
llow
s:
aft
er
a co
nce
ntr
ate
d o
ne,
equili
bra
tion
time
ism
easu
reab
ly
incr
ease
d.
Rin
se
the
ele
ctro
de
s w
ith d
istille
d
wate
r an
d b
lot
dry
. In
to
a sm
all
pla
stic
cap
co
nta
inin
g
a sm
all
stirr
ing
b
ar,
po
ur ~
10
ml
so
lutio
n.
Imm
erse
th
e
ele
ctro
de
s an
d ch
eck
for
and
dis
lodge
any
air
bubble
s.
Sta
rt
gentle
m
agne
tic stirr
ing.
After
5 m
inute
s,
read
an
d re
cord
th
e pote
ntial.
Con
tinue
with
th
e
sam
ple
solu
tions
in
this
m
anne
r.
6.
Pre
pare
a
lea
st
squa
res
curv
e
from
th
e st
an
da
rds'
6
. Th
e m
illivolt re
ad
ing
s ar
e tr
eate
d
as
the
in
depe
nden
t d
ata
. C
ompu
te
pe
rce
nt
F~
in
the
un
know
ns.
va
ria
ble
. Th
e lo
g o
f th
e
F~ c
once
ntr
atio
n
in
ppm
is
the
depe
nden
t va
ria
ble
.
Com
pile
d by
M.
Cre
mer 12
0
FeO
IN SILICATES, CA
RBON
ATES
, AND
PHOS
PHAT
ES,
USING
THE
METR
OHM
TITR
ATOR
Ferr
ous
oxide
(FeO)
is de
term
ined
by
titration
with
sta
ndar
d di
chro
mate
solution us
ing
diphenylamine
sulf
onic
ac
id as
th
e indicator.
A probe
colo
rime
ter
is used. 6
The
sample is
de
comp
osed
by
boi
ling
with
HF-H
^SO^
The
mixture
is ad
ded
to a
phosphoric-boric-sulfuric
acid solution to c
ompl
ex f
erri
c an
d fl
uori
de io
ns.
The
dissolution
method on
ly partially
atta
cks
pyrite,
chromite,
siderite,
tourmaline,
organic
matter^, and
other
rela
ted
mate
rial
s. 5»?
in
th
e ab
senc
e of
comp
lica
tion
s, precision
is within 0.1
perc
ent
(absolute),
accuracy is
±
1 pe
rcen
t (r
elat
ive)
, an
d detection
limit
is
0.02
pe
rcen
t FeO.
Disc
ussi
on of t
he procedure
may
be found
in Re
fere
nces
1, 4, an
d 7.
Reag
ent
(all
ch
emic
als-
reag
ent
grade):
1:1:
1 H20, 48
pe
rcen
t HF,
98 percent
H2S0
4 (300 m
l ea
ch in a
polyethylene bo
ttle
)
5 pe
rcen
t H3P0
4 -
2 pe
rcen
t H2
S04
- 0.8
perc
ent
H3B0
3 -
(780
0 ml H2
0, 390
ml H3
P04
, 20
0 ml
, 65
g
H3B0
3 mi
xed
in a
larg
e Pyrex
dispenser
bott
le)
Sodi
um D
iphenylamine Su
lfon
ate:
0.
1 percent
aqueous
solu
tion
Potassium
Dichromate:
0.1
N solution,
prepared from N
BS Standard No.
13bb,
at 20
°C (9
.806
3g m
ade
to 2
000
ml
with H2
0)
FeO
Spik
e:
0.1
N solution (~39.20
to 39.25
g Fe(NH4
)2(S
04)2-6H2
0, 5
ml H2
S04
, ma
de to 10
00 m
l wi
th water)
Procedure
Comm
ents
1.
Weig
h a
0.5
gram p
ortion o
f th
e thoroughly m
ixed
1.
If the
samp
le is gr
ound
much
finer, su
rfac
e ar
ea is
samp
le gr
ound
to
pa
ss 10
0 mesh.
Transfer to
a
50 m
l increased
whic
h re
sult
s in m
ore
exposure to th
e platinum c
ruci
ble
which
has
a ti
ghtl
y fi
ttin
g cover.
atmosphere.
Some
fe
rrou
s oxide
can
be oxidized to
ferr
ic o
xide
.
121
2. 3. 5.
6. 7.
In
a fu
me
hood
, an
d w
ith
a p
lastic
gra
duate
, ad
d 13
-14
ml
HF-
H2$
04 m
ixtu
re
to
the cru
cib
le
and
imm
edia
tely
co
ver.
Qu
ickl
y p
lace
th
e co
vere
d cru
cib
le
on
a silic
a
tria
ngle
o
ver
a ve
ry
sma
ll B
unse
n burn
er
with
a
flam
e ab
out
one-h
alf
inch
hig
h.
To
bring th
e solu
tion
to
a b
oil
pro
mptly
, heat
the
cru
cib
le w
ith
a h
an
d-h
eld
T
irrill
bu
rne
r,
dire
ctin
g
the
fla
me
tow
ard
the
botto
m
and
side,
un
til
a sm
all,
but
steady
flow
of
stea
m
esca
pes
from
th
e cru
cib
le.
Rem
ove
the
T
irrill
flam
e an
d co
ntin
ue
to b
oil
ge
ntly
for
seve
n (7
) m
inu
tes.
Th
e sm
all
flow
o
f st
eam
sh
ou
ld
con
tinu
e
thro
ughout.
While
sa
mpl
e is
b
oili
ng
, ad
d 30
0 m
l o
f th
e
H3P
04-H
3B03
-H2S
04
solu
tion
to
a 60
0 m
l be
aker
co
nta
inin
g
a K
el-F
stirr
ing
ba
r.
Usi
ng
a stirr
ing
rod
to
secu
re
the
lid
, re
mov
e th
e
cru
cib
le
from
th
e
flam
e w
ith B
lair
ton
gs;
im
mer
se
the
cru
cib
le
and
cove
r in
th
e
beak
er conta
inin
g th
eH3
P04_
H3B
03-H
2S04
so
lutio
n.
2.
Hydro
fluoric
aci
d
is
a st
ron
g ca
taly
st
for
the
oxid
ation
of
ferr
ous
sulfate
in
air.
Th
ere
fore
, th
e
so
lutio
n
mus
t be
b
rou
gh
t to
a
boil
as
soon
as
p
oss
ible
so
th
at
the a
ir
in
the cru
cib
le
is
dis
pla
ced
by
stea
m.
The
ind
ica
tor
may
a
lso
be
p
art
ially
oxi
diz
ed
in
th
e
abov
e so
lutio
n.
This
co
nd
itio
n
prod
uces
an
in
dis
tin
ct
end
poin
t w
hich
oc
curs
befo
re
the
equiv
ale
nce
poin
t.
The
prob
lem
is
ov
erco
me
with
phosp
horic
aci
d
whi
ch
low
ers
the oxid
ation
po
ten
tia
l o
f th
e fe
rric
-ferr
ous
iro
n
syst
em
by
com
plex
ing
with
fe
rric
io
ns.
H3B
03
conve
rts
HF
to flu
ob
oric
aci
d
whi
ch
rem
oves
th
e cata
lytic oxid
ation
pow
er
of
HF.
A
lso
attack
on
th
e
glas
swar
e is
m
inim
ize
d.
122
8.
Usi
ng th
e stirr
ing
ro
d or
pla
tinum
to
ng
s,
rem
ove
and
rinse
th
e cru
cib
le,
its
cove
r,
the
tongs,
an
d ro
d.
9.
Add
8-10
dro
ps o
f di
phen
ylam
ine
sulfo
na
te
ind
ica
tor
solu
tion.
10,
11.
12.
13.
14.
Turn
on
th
e fo
ur
pow
er
switc
hes.
B
lock
th
e pr
obe
lig
ht
path
by
pa
cing
th
e tip o
f a
penci
l be
twee
n th
e m
irro
r an
d th
e m
etal
pr
obe
post
, "T
RANS
MIT
TANC
E ZE
RO"
knob
until
perc
ent
tra
nsm
itta
nce
.
Turn
th
e th
e m
eter
re
ads
0
Pla
ce
the
beak
er
on
the
Met
rohm
S
tirr
er
(E
549)
. Im
mer
se
the
prob
e tip
to
a de
pth
beyo
nd
the
rect
an
gu
lar
ho
le,
but
not
beyo
nd
the
top
of
the
prob
e tip
. If air
bubb
les
appe
ar
in
the
prob
e tip o
peni
ng,
slightly agita
te
the
prob
e si
dew
ays.
Po
sitio
n
the
I^C
^Oy
disp
ense
r tip
so
th
at
the
prob
e re
spon
ds ra
pid
ly
to
the
colo
r o
f th
e stirr
ed
solu
tion after
each
ad
ded
drop
.
Turn
th
e "A
BSO
RBAN
CE
ZERO
" fc
nob
until
the
met
er
read
s ze
ro
on
the
abso
rban
ce s
cale
. P
ress
ST
ART
on
the
Titra
tor
(E
526)
. Th
e re
d pilot
ligh
t go
es
out,
and
auto
mat
ic titr
atio
n
be
gin
s.
Not
e th
e stirr
ing
sp
eed
and
ad
just
if
nece
ssar
y.
Rec
ord
the d
igita
l re
adou
t w
hen
the
red
pilot
light
com
es
on.
Then
co
ntin
ue w
ith
step
s 15
an
d 16
. If
th
e r
eado
ut
is
exc
ess
ive
ly s
mal
l or
th
e re
d p
ilot
lig
ht
neve
r co
mes
on
, pr
ocee
d to
st
ep
17
.
8. 9. 10.
12.
13.
14.
The
pla
tinum
-tip
ped
tong
s sh
ould
not
be
imm
erse
d in
th
e so
lutio
n
so
deep
ly th
at
the
ste
el
port
ion
of
the
tong
s is
in
th
e liq
uid
.
At
this
poin
t,
the titr
atio
n
may
be
cont
inue
d m
anua
lly w
ith
a su
bje
ctiv
e
deci
sion
as
to
the
end
po
int.
T
his
is
de
fin
ite
ly pre
ferr
ed
whe
n th
e Fe
O
con
cen
tra
tion
is
lo
w,
for
the
syst
em
tend
s to
overt
itra
te
in
this
in
sta
nce
. O
nly
the
titr
ato
r an
d stirr
er
need
be
act
ivate
d.
A 52
0 nm
filte
r is
us
ed
in
the
open
ing
at
the
front
of
the
prob
e co
lorim
ete
r (P
C/6
00).
The
disp
ense
r tip
shou
ld
be
plac
ed
as
near
as
poss
ible
up
stre
am
(with
re
fere
nce
to
th
e stirr
ing
d
ire
ctio
n)
from
th
e pr
obe.
The
stirr
ing
sp
eed
mus
t ne
ver
be fa
st
enou
gh
to
sca
tte
r air
bubb
les
from
th
e vo
rtex
into
th
e so
lutio
n
The
purp
le
colo
r sh
ould
pers
ist
for
at
least
30
se
cond
s.
How
ever
, th
e pilot
light
has
com
e on
a
fte
r th
e tim
e d
ela
y se
t on
th
e titr
ato
r (3
0 se
cond
s).
If
the
end
poin
t is
re
ache
d ve
ry
soon
or
is
ne
ver
reac
hed
(the
red
light
did
no
t co
me
on
), e
ith
er
there
is
ve
ry litt
le
or
no
FeO
or
so
muc
h th
e titr
atio
n
take
s a
very
lo
ng
time.
See
Ste
p 17
.
123
15.
Rem
ove
and
rin
se
dis
pense
r an
d pr
obe;
in
spe
ct
the
solid
s
in
the
bo
ttom
of
the
be
ake
r.
A w
hite
po
wde
r is
no
rmal
(S
iO?,
C
aF),
b
ut
bla
ck
spec
ks
and
gritty
part
icle
s
are
evi
dence
o
f un
deco
mpo
sed
sam
ple.
If
this
occ
urs
, th
e
de
term
ina
tion
sh
ould
be
re
pe
ate
d,
usi
ng
a
sma
ller
po
rtio
n
or
one
whi
ch
has
been
m
ore
fin
ely
gr
ound
. F
loating
bla
ck
pa
rtic
les
ind
ica
te
org
anic
m
ate
rial.
In
the
abse
nce
of
unde
com
pose
d sa
mpl
e,
redu
ce
the
da
ta
as
follo
ws:
15.
The
dis
pense
r sh
ould
al
way
s be
re
mov
ed
imm
ed
iate
ly
to
avo
id a
lte
ratio
n
of
the
titr
ant
by diffu
sio
n.
In
the
even
t o
f un
deco
mpo
sed
sam
ple
and/o
r org
anic
m
ate
rial,
the
fo
llow
ing
note
sh
ould
be
ad
ded
at
the
end
of
the
report
: "S
ulfid
es,
refr
acto
ry m
inera
ls,
and
org
an
ic
mate
rials
, if
pre
sen
t,
pre
vent
the
a
ccu
rate
d
ete
rmin
atio
n
of
FeO
".
ml
0.1
N x
71.8
4 x
100
pe
rce
nt
sam
ple
Wei
ght
(mill
igra
ms)
= P
erc
ent
FeO
Sim
plif
ied:
ml
K2C
r20?
x 718.4
= P
erc
ent
FeO
Sam
ple
Wei
ght
(mill
igra
ms)
Un
its: (m
l)
(meg
/ml)(
mg/
meq
)100
p
erc
en
t =
FeO
m
g
16.
If
the
analy
st
choo
ses,
he
m
ay b
egin
a
no
the
r sa
mpl
e (s
tep
2)
betw
een
steps
13
and
14.
17.
With
an
othe
r port
ion
of
the
sa
me
sam
ple,
re
pe
at
ste
ps
1 th
rough 9
, o
nly
if
the la
st
sent
ence
of
step
14
is
ob
tain
ed
.
18.
Add
5.0
ml
of
the
Fe
O sp
ike solu
tion
and
proc
eed
with
ste
ps
10
thro
ugh
15.
18.
The
spik
e so
lutio
n
guar
ante
es
an
end
po
int.
124
19.
Sta
nd
ard
ize
th
e
spik
e solu
tion
thre
e
times
by
add
ing
19.
Bec
ause
th
e
che
mis
try
is
no
t exactly m
atch
ed,
the
5
ml
to
300
ml
of
the
^0
4-^
60
3-^
50
4
(FeO
) sp
ike
m
ay e
xcee
d (F
eO)
spik
e
plu
s (F
eO)
so
lutio
n
to
whi
ch
indic
ato
r is
ad
ded
(see
st
eps
6 an
d sa
mpl
e.
In th
is
case
, it
is
assu
med
(F
eO)
sam
ple
is
9).
P
roce
ed
thro
ugh
the
rem
aind
er o
f th
e
aver
age
in
belo
w
the
dete
ctio
n lim
it,
mille
lite
rs
I^C
^Oy
of
the
th
ree titr
atio
ns
from
th
e m
illilite
rs
used
fo
r th
e
spik
e
plu
s sa
mpl
e.
Pro
ceed
with
th
e calc
ula
tions
in
step 1
5.
Com
pile
d by
P.
Klo
ck
and
M.
Cre
mer 125
REFERENCES
1.
Hill
eb
ran
d,
W.
F.,
Lundell,
G
. E.
F
.,
Bright,
H.
A.,
Hof
fman
, J.
I.
, 19
53,
Ap
plie
d
Inorg
anic
A
naly
sis
: 2n
d e
d.,
Ne
w Y
ork
, Jo
hn
Wile
y an
d S
ons,
p.
90
7-92
2.
2.
Instr
uctio
n fo
r U
se
E5
26
/Titra
tor
3.
Instr
uction
for
Use
E
535/
Dos
imat
4.
Kolthoff
and
Sa
nd
ell,
19
69,
Tex
tboo
k of
Quantita
tive
Inorg
anic
A
naly
sis,
3
rd ed.;
1952
p.
71
1-71
3.
5.
Nic
ho
lls,
G.
D.,
1960
, T
echn
ique
s in
S
edim
enta
ry
Geoch
em
istr
y:
Jou
rna
l o
f S
edim
enta
ry P
etr
olo
gy,
v.
30
, no
. 4
p.
603-
612.
6.
Op
era
ting
In
str
uctio
ns
for
Brin
kman
n P
C-6
00
Pro
be C
olo
rim
ete
r.
7.
Pec
k,
Lee,
19
64,
Sys
tem
atic
A
naly
sis
of
Sili
ca
tes:
U.S
. G
eo
log
ica
l S
urve
y B
ulle
tin
11
70,
p.
39-4
2.
8.
Shapiro,
Leon
ard,
19
75,
Rap
id
Analy
sis
of
Sili
cate
, C
arbo
nate
an
d P
hosp
hate
R
ocks
(R
evis
ed e
ditio
n):
U
.S.
Geolo
gic
al
Sur
vey
Bulle
tin
1401
, pg
. 57
-58.
126
DET
ERM
INAT
ION
OF
TOTA
L M
n W
ITH
(f
rom
K
olthoff
and
Sa
nd
ell,
p.
677)
This
m
etho
d is
re
port
ed
to
be
the m
ost
acc
ura
te fo
r th
e d
ete
rmin
atio
n
of
man
gane
se
whe
n pre
sent
in
maj
or
con
cen
tra
tion
s (>
1 perc
ent)
. Th
e sa
mpl
e is
fu
sed
with
N
ap02
an
d ta
ken
into
solu
tion
with
H
N03
an
d ^O
o.
Fo
llow
ing
p
relim
ina
ry t
rea
tme
nt
with
N
aBi0
3 to
dest
roy
reduci
ng
sub
sta
nce
s,
the
M
n**
is
oxi
diz
ed
to
M
n'*
with
b
ism
uth
ate
. A
mea
sure
d ex
cess
o
f fe
rrous
sa
lt
is
adde
d to
re
act
w
ith
the
Mn?
"1",
and
the
exce
ss
of
Fe"1"
1" is
th
en
de
term
ine
d
by t
itra
tio
n
with
st
an
da
rd
KMn0
4 so
lutio
n.
Rea
gent
s (a
ll
che
mic
als
-re
ag
en
t g
rad
e):
, po
wde
red.
HN
03,
con
cen
tra
ted
, b
oile
d
to
rem
oval
of
yello
wis
h
tinge o
f liq
uid
an
d va
por
phas
e.
Nitr
ous
aci
d
mus
t be
abse
nt.
Pre
pare
fr
esh
d
aily
.
1:30
H
N03
, p
rep
are
d
fresh
d
aily
, usi
ng boile
d,
coo
led
co
nce
ntr
ate
d
HN03
an
d b
oile
d
and
coo
led
d
istille
d
H20
.
NaB
i03,
po
wde
r.
Ava
ilab
le
oxyg
en
sho
uld
co
rre
spo
nd
to
a
t le
ast
75
pe
rce
nt
NaB
i03-
C
hlo
rid
e
and
man
gane
se
should
be
abse
nt.
Sta
ndar
d so
lutio
ns:
0.10
00
N K
2Cr2
0y.
Pre
pare
d by
dis
so
lvin
g 4
.903
5 g
NBS
sam
ple
No.
13
6c
in b
oile
d,
coo
led
d
istille
d
wate
r an
d diluting
to
1000
m
l at
20°C
.
0.1
N F
e(N
H4)
2(S
Oa)
2'6H
20.
Pre
pare
d fr
om
re
agent
grad
e cry
sta
ls.
Dis
solv
e
39.2
g
in
1 lite
r o
f 5
pe
rce
nt
(v/v
) ^$
84.
Mus
t be
st
an
da
rdiz
ed
daily
u
sin
g th
e
0.10
00
N K
gC^O
y.
0.1
N K
Mn0
4.
Pre
pare
d fr
om r
ea
ge
nt
grad
e KM
n04-
S
tan
da
rdiz
ed
fr
eq
ue
ntly
by titr
atin
g w
ith re
ce
ntly
(sam
e da
y)
sta
nd
ard
ize
d
Fe(
NH
4)2(
S0
4)2
'6H
20
(ab
ove
).
Pro
cedu
re
Com
men
ts
1.
Wei
gh
a 50
-rog
sa
mpl
e in
to
a zi
rco
niu
m cru
cib
le.
2.
Add
0.5
g
Na2
02
and
mix
by
gently sh
aki
ng.
3.
Fuse
ov
er
a sm
all
Tirrill
flam
e,
taki
ng
care
to
a
void
spattering.
Set
on
a
porc
ela
in
pla
te
to
cool.
127
Pla
ce
cru
cib
le
in
a 25
0-m
l be
aker
an
d co
ver
with
a
wat
ch
gla
ss.
5.
With
th
e b
eake
r co
vere
d,
add
seve
ral
ml
dis
tilled
H20
by s
quirting it
into
th
e cru
cib
le
from
a
was
h b
ott
le
thro
ugh
the
be
aker
sp
ou
t.
6.
After
vig
oro
us
react
ion
has
sub
sid
ed
, re
mov
e w
atch
gl
ass
and
qu
ickly
add
5
ml
boile
d
con
cen
tra
ted
HN
03
and
a sq
uirt
of
30 perc
ent ^2.
Rep
lace
w
atch
gl
ass
.
7.
Dig
est
at
stea
m b
ath
tem
pe
ratu
re fo
r ab
out
2 hours
. C
ool
to r
oom
te
mp
era
ture
.
8.
Add
0.5
g N
aBi0
3 (if n
eith
er
a pre
cip
itate
no
r a
pink
co
lor
is
prod
uced
, ad
d 0.
5 g
mor
e b
ism
uth
ate
).
9.
Add
drop
wis
e a
6 p
erc
en
t solu
tion of
sulfu
rous
aci
d
(H2S
03)
un
til
colo
r or
p
recip
ita
te
dis
appears
.
10.
Add
seve
ral
gla
ss boili
ng b
eads
an
d b
oil
4-5
min
utes
11.
Rem
ove
from
heat
and
ch
ill
to
10°C
in
an
ic
e bath
. Ad
d 10
ml
of
the
boile
d,
conce
ntr
ate
d
HN
03.
12.
Add
1 g
NaB
i03
and
stir
for
1-2
m
inute
s.
Som
e o
f th
e b
ism
uth
ate
sh
ould
re
mai
n u
nd
isso
lve
d.
13.
Add
50 m
l co
ld
1:30
HN
03
and
mix
.
14.
Filte
r th
roug
h tw
o or
m
ore
thic
kne
sse
s of
glas
s fib
er
pape
r in
to
a w
ide-
mou
th
500-
ml
Erle
nmey
er fla
sk.
8.
Bis
mut
hate
is
ad
ded
to oxid
ize
any
red
uci
ng
su
bst
an
ces.
9.
Sulfu
rous
aci
d is
ad
ded
to
redu
ce all
the
man
gane
se
pre
sen
t to
Mn
++.
11.
Oxi
da
tion
of
the
Mn
w
ill
no
t be
quantita
tive u
nle
ss
the
sam
ple
is
quite
cold
an
d th
e
conce
ntr
atio
n
of
the
HN
03
is
at
lea
st
10
pe
rce
nt
and
pre
fera
bly
20
pe
rce
nt
by v
olum
e.
HC1
and
HF m
ust
be
abse
nt.
12.
The
oxid
atio
n
rea
ctio
n
of
man
gane
se
to
perm
anga
nate
is
:
2Mn+
2+
5 N
aBi0
3 +
14H
+-» 2
M
n04~
+
5 Na
+ +
5 B
i+3
+ 7
H0
.
14.
To
rem
ove
exce
ss
bis
muth
ate
filter
the s
ampl
e by
pla
cing t
he
pa
per
in
a B
uchn
er
funnel
whi
ch
empt
ies
into
th
e E
rlenm
eyer
flask w
ith
in
a bell
jar,
w
hich
is
attach
ed
to
a va
cuum
pu
mp.
A
ll co
nta
ct o
f th
e
sam
ple
with
o
rga
nic
m
att
er
(suc
h as
pa
per
or
rub
be
r)
mus
t be
avo
ided.
15.
Was
h th
e p
recip
ita
te
tho
rou
gh
ly w
ith
1:3
0
16.
Add
3 m
l co
nce
ntr
ate
d
17.
Usi
ng
a b
ure
tte
or
a vo
lum
etr
ic
pip
ett
e,
add
an
exce
ss of
the
st
an
da
rd
ferr
ou
s am
mon
ium
sulfate
18.
Titra
te
the
exce
ss
Fe++
with
th
e st
andard
KM
nCty
to
the
firs
t pe
rman
ent
pink
tinge.
15.
Bis
mut
hate
sh
ows
a g
rea
t te
nden
cy to
re
tain
pe
rman
gana
te.
16.
H3P
04
is
adde
d to
co
mpl
ex t
he
Fe
+3
form
edd
urin
g
the
titr
atio
n.
Thus
th
e o
xid
atio
n
pote
ntial
of
the
iron
syst
em is
re
du
ced
, re
sultin
g in
a
sharp
en
d p
oin
t.
17.
A 50
mg
sam
ple
whi
ch
con
tain
s 74
p
erc
en
t M
iO w
ill
require 3
0-40
ml
0.1
N Fe
( ̂4)2
(504)
2 6
H20
. Th
e re
du
ctio
n
rea
ctio
n
of
perm
anga
nate
to
m
anga
nous
salt
is
^104
" +5
Fe+2
+8H
"1'
Mn+
2+5F
e+3
+4 H
20.
129
Calc
ulat
ions
:
I.
From
the
normality
of t
he Fe
(NH.
)9(
$0,)
9.6H9
0 solution,
calculate
the
FeO
equi
vale
nt of
one m
l Fe
(NH4
)2(S
04)2
.6H2
0:
^
**
<L
mg
FeO
_
N 7
, ,)
0(S
OJ
0.6
H00
"
lTe(
NH
/1)0
(SO
j0.6
H00
x "''
ml
Fe(N
H4
)2(S
04
)2.6
H20
II.
Ca
lcu
late
th
e
FeO
equiv
ale
nt
of
one
ml
KMnO
. so
lutio
n:
mg Fe
O N.,
.. n
x 71.8
4 ml
KMn0
4 "
III.
C
alc
ula
te
the
M
nO e
qu
iva
len
t of
the
KM
nO,
so
lutio
n:
ml
KMn0
4 =
NKM
n04
x 70
'94
IV.
Qml Fe(NH4
)2(S
04)2
.6H2
0 adde
d x
m] Fe
(NH^
2(go
4)2
.6H2
o]-
(m1
KMn°
4 X ^^] X
70'94
= m*
M"°
71.8
4 x
5
V.
mg M
nO x
10
0 .
samp
le w
t in m
g
Comp
iled
by
S.
Neil
REFE
RENC
ES
Kolt
hoff
, I.M.t
and
Sandell, E.B.,
1952
, Te
xtbo
ok o
f Quantitative Inorganic
Analysis,
3d ed
: New
York,
The
Macmillan
Co., 75
9 p.
130
MER
CURY
IN
R
OC
KS
AND
MIN
ER
ALS
(Ada
pted
fr
om
De
term
ina
tion
o
f S
ub-m
icro
gram
quantities o
f m
ercu
ry b
y a
tom
ic
abso
rptio
n
spe
ctro
ph
oto
me
try
by
W.
R.
Hat
ch
and
W.
L.
Ott
, A
naly
tical
Chem
istr
y, v.
40,
no.
14,
Dec
embe
r 19
68,
p.
20
85
-20
87
.)
The
sam
ple
is
tre
ate
d w
ith su
lfu
ric
and
nitric a
cid
. P
otas
sium
pe
rman
gana
te,
pota
ssiu
m pers
ulfate
, an
d so
dium
ch
loride-h
ydro
xyla
min
e
su
lfa
te
are
ad
ded.
L
astly,
stan
nous
sulfate
is
ad
ded,
an
d th
e v
esse
l is
im
media
tely
attach
ed
to
a cl
ose
d
syst
em a
ppara
tus.
M
ercu
ry
gas
is
libera
ted
and
carr
ied
by n
itro
ge
n
thro
ugh
a q
ua
rtz
win
dow
ed
tube.
Abs
orba
nce
of
the
em
itted lig
ht
from
a
hollo
w
cath
ode
mer
cury
lam
p o
ccu
rs
at
253.
7 nm
and
is
re
ad w
ith
an
atom
ic
abso
rptio
n
unit.
Rea
gent
s (a
ll ch
em
icals
-reagent
gra
de):
Gla
ssw
are
used
fo
r th
e fo
llow
ing m
erc
ury
sta
ndard
s m
ust
be
conditi
oned fo
r appro
xim
ate
ly
two
wee
ks
whe
n th
e so
lutio
ns
are
dis
card
ed
an
d re
mad
e in
th
e
sam
e gla
ssw
are
, rin
sed
o
nly
with
d
istille
d w
ate
r.
Mer
cury
sto
ck
so
lutio
n-d
isso
lve
0.
1354
g
of
merc
uric
ch
lorid
e
(HgC
l2)
in
a m
ixtu
re o
f 75
m
l H
20
and
10 m
l H
N03
. D
ilute
to
10
0 m
l w
ith
H20
. 1
ml
= 1
mg
Hg
= 10
00 p
pm.
Mer
cury
in
term
ed
iate
so
lutio
n-p
i pe
t 2
ml
of
the
st
ock
m
ercu
ry so
lutio
n
into
a
mix
ture
of
~150
ml
of
wat
er
and
0.4
ml
HN
03.
Dilu
te
to
200
ml.
Pre
pare
fr
esh
d
aily
. 1
ml
= 10
pg
Hg
=
10
ppm
.
Mer
cury
wo
rkin
g solu
tion-p
i pet
2 m
l o
f th
e
inte
rmedia
te
mer
cury
so
lutio
n
into
a
mix
ture
of
~150
ml
of
wate
r an
d 0.4
m
l H
N03
. D
ilute
to
20
0 m
l. P
repa
re
fre
sh
da
ily.
1 m
l =
0.1
pg
Hg
=
0.1
pp
m.
Pot
assi
um
perm
anga
nate
solu
tion-d
issolv
e w
ith
heat
5 g
pota
ssiu
m
perm
anga
nate
in
w
ate
r.
Dilu
te
to
100
ml
with
w
ate
r.
Pot
assi
um pers
ulfate
solu
tion-d
issolv
e w
ith
heat
5 g
1^2
03
in
H20
. D
ilute
to
10
0 m
l.
Sod
ium
ch
lorid
e-h
ydro
xyla
min
e sulfate
so
lutio
n-d
isso
lve
12
g
of
sodi
um
chlo
ride
and
12
g hyd
roxy
lam
ine su
lfa
te
in
H20
. D
ilute
to
10
0 m
l w
ith
wate
r.
Su
lfu
ric acid
, 0.
5N-1
4 m
l co
nce
ntr
ate
d
H2S
04
to
one
lite
r H
20.
Sta
nnou
s sulfate
so
lutio
n-a
dd
25
g st
anno
us
su
lfa
te
to
250
ml
0.5N
H
2S04
. T
his
mix
ture
is
a
susp
ensi
on
and
mus
t be
stirr
ed
contin
uousl
y d
urin
g
use.
Su
lfu
ric-n
itric m
ixtu
re-a
dd
two
pa
rts
con
cen
tra
ted
H
2S04
to
on
e p
art
co
nce
ntr
ate
d
HN
03.
An
tifo
am
B
-sili
cone
em
uls
ion.
131
App
arat
us:
Ato
mic
a
bso
rptio
n
spe
ctro
ph
oto
me
ter.
V
arie
n AA
6 eq
uipp
ed w
ith
a re
cord
er
set
at
0.5
inch
es/
min
.
Mer
cury
hollo
w
cath
ode
lam
p,
Wes
tingh
ouse
, ar
gon
fille
d.
Abso
rptio
n
ce
ll w
ith
c^ua
rtz
win
dow
s.
Obt
aine
d fr
om V
arien.
Flo
wm
eter
ca
libra
ted
in
SC
FH air
un
its
from
0
to
10.
Nitr
ogen hig
h-p
urity
ca
rrie
r ga
s.
U tu
be filled w
ith
CaS
04.
Gas
was
hing
bo
ttle
-25
0 m
l ca
pa
city
-eq
uip
pe
d w
ith
a specia
lly m
odifi
ed
sto
pp
er
to
whi
ch
is
att
ach
ed
a
12-m
m
dia
mete
r fr
itte
d cylin
der.
Tygo
n tu
bin
g.
132
Pro
cedu
reC
omm
ent
1.
Wei
gh
and
tra
nsfe
r 0.
2 to
1.0
g
pow
der
to
a 25
0 m
l E
rlenm
eyer
fla
sk
equi
pped
with
a
wat
ch
gla
ss.
2.
Add
to
the flask
7.5
m
l 2:
1 H2
S04-
HN
03
mix
ture
.R
eflu
x^on
a
ho
tpla
te
set
at
a te
mpera
ture
bet
wee
n 50
°C
and
95°C
fo
r tw
o h
ou
rs.
Sw
irl
the
flask
occasio
nally
.
3.
Coo
l. W
ith
a g
rad
ua
te,
add
100
ml
H20
dow
n th
e
watc
hgla
ss
as
well
as
down
th
e
sides
of
the
flask.
4.
Add
1 m
l K
Mn0
4, sw
irl,
and
wait at
lea
st
15m
inu
tes.
If
the
pu
rple
co
lor
fad
es,
ad
d m
ore
KMn0
4
5.
After
the
purp
le co
lor
pe
rsis
ts,
add
2 m
l S
et
asi
de overn
ight.
6.
Nex
t m
orn
ing
, pr
epar
e th
e fo
llow
ing
sta
nd
ard
s in
duplic
ate
in
25
0 m
l E
rlenm
eyer
fla
sks:
ml
0.1
ppm
Hg
so
lutio
nm
l H
20 100 98
%
94
Pre
pare
on
e 10
ml-0.1
pp
m
Hg
+ 90
ml-H
^O to
us
e to
se
ason
th
e
equi
pmen
t.
7.
Add
to
each
st
andard
7.
5 m
l 2:
1 H
2S04
-HN
03
' m
ixtu
re,
1 m
l K
Mn0
4,
and
2 m
l K2
S20Q
.
1.
The
we
igh
t is
p
red
ica
ted
upo
n th
e a
nticip
ate
d
Hg
co
nce
ntr
atio
n,
the h
ighest
st
andard
be
ing
0.
6 yg
.
2.
Hg
in
org
an
ic m
ate
ria
ls
is
report
ed
to
be st
able
at
tem
pe
ratu
res
£
50°C
. In
in
org
anic
mate
rials
, it
is
report
ed
to
be st
ab
le at
tem
pe
ratu
res
_< 95
°C.
3.
Vol
umes
th
roughout
are
ke
pt
at
appro
xim
ate
ly
100
ml
exc
lusi
ve of
adde
d re
agents
.
4.
Som
e sa
mpl
es
con
tain
ing
org
an
ic m
ate
ria
l st
ubborn
ly
fade
ev
en
with
10
ml
KMn0
4 an
d a
paus
e of
seve
ral
ho
urs
. T
his
ha
s be
en
foun
d to
re
su
lt
in
a solu
tion
whi
ch
foam
s u
nco
ntr
olla
bly
whe
n th
e carr
ier
gas
is
appl
ie
d.
5.
The
additio
n
of
K2$2
®8
in
ad
ditio
n
to
oxi
da
nt
KMn0
4 gu
aran
tees
th
e oxi
datio
n
of
orga
no
mer
cury
co
mpo
unds
. M
ercu
ry
is
sta
ble
in
a
cid
so
lutio
n
and
in
the
pres
ence
of
KMn0
4.
6.
Even
fo
r th
e
sta
nd
ard
s,
volu
mes
ar
e o
nly
ap
prox
imat
e be
caus
e st
an
da
rds
and
unkn
owns
ar
e tr
ea
ted
exactly th
e
sam
e.
Mic
rogr
ams
of
mer
cury
are
plo
tted
as
ab
ciss
a
and
abso
rban
ce
as
ord
inate
. T
here
fore
, vo
lum
es
ao
not
ente
r in
to
ca
lcu
latio
ns.
Gla
ss
pip
ettes
are
used
be
caus
e m
ercu
ry a
dher
es
to
pla
stic.
133
8.
On
the
AA p
eak
at
253.
7 nm
, alig
n
the
ce
ll,
the
lam
p,
etc
.,
usin
g abso
rptio
n,
A ga
in
and
slit
0.5
nm.
Zero
an
d calib
rate
th
e r
eco
rder.
9.
Bef
ore
be
gin
nin
g t
he a
na
lysi
s,
turn
on
th
e N2
ga
san
d se
t th
e re
gu
lato
r to
20
psi.
With
th
e st
opco
ck
at
bypa
ss,
the
flow
met
er
shou
ld
read
5
SCFH
whi
ch
conv
erts
to
3
SCFH
w
hen
the
ca
rrie
r ga
s flo
ws
thro
ugh
the so
lutio
n
in
the
bottle
.
10.
Pou
r th
e co
nten
ts of
the
hig
he
st
stan
dard
(i.e
.,
the
1 ng
) in
to
the
gas
was
hing
bottle
. R
inse
th
e E
rlenm
eyer
flask
spa
rin
gly
th
ree
time
s.
Pou
r th
e rinsi
ngs
into
th
e bottle
. Ad
d 2
ml
NaC
l- (N
H20
H)2
^$0
4.
Rapid
ly s
wirl
the
bottle
. C
heck
th
at
the
stop
cock
on
th
e st
oppe
r is
tu
rned
to
by-
pass
. In
sert
th
e st
oppe
r in
th
e bottle
an
d se
cure
th
e ball
join
ts-o
ne
to
th
e N£
ca
rrie
r ga
s,
the
oth
er
to
the
dry
ing
tube.
11.
Imm
edia
tely
add
5
ml
SnS0
4 an
d cl
ose
the
syst
em w
ith
a pe
nny
sto
pp
er.
12.
Sta
rt
a st
op w
atch
. A
fter
75
seco
nds,
tu
rn
the
stop
cock
to
d
ire
ct
the
ca
rrie
r ga
s th
roug
h th
e so
lutio
n
in
the
bottle
.
8.
A w
ide
slit
is
acce
ptab
le b
ecau
se r
educ
ed m
ercu
ry
vapo
r in
th
e abso
rptio
n
cell
has
very
little
sp
ect
ral
inte
rfe
ren
ce.
Lig
ht
ou
tpu
t is
in
crea
sed
and
pre
cisi
on
is
im
prov
ed.
10.
Upon
be
ing
sw
irle
d,
the so
lutio
n
beco
mes
co
lorle
ss.
NaC
l-(N
H20
H)2
H2$
04
redu
ces
exce
ss
Mn0
2 ~
and
assu
res
tha
t fr
ee
chlo
rine
is
abse
nt
befo
re
mer
cury
is
re
duce
d.
11.
The
reduct
ion
react
ions
are:
Bec
ause
th
e co
uple
Hg^
^-H
q4"
is
a st
ron
ge
r oxid
izin
g
coup
le
than
H
g+*-
H9.
the r
ed
uci
ng
ag
ent
Sir*
-*,
pres
ent
in
exce
ss,
firs
t re
duce
s th
e m
erc
uric
ion
and
then
th
e m
ercu
r iou
s io
n.
12.
The
red
uct
ion
re
act
ion
is
report
ed
to
com
men
ce
from
60
to
90
seco
nds
aft
er
the
ad
diti
on
of
SnS0
4.
134
13 14 15
Not
e on
th
e r
eco
rder
tra
ce
the
m
axim
um a
bso
rptio
n
valu
e.
Whi
le w
aitin
g fo
r th
e r
eadin
g
to
desc
end
to
zero
, tr
an
sfe
r th
e 0.6
yg
sta
nd
ard
to
th
e
seco
nd
gas
was
hing
bo
ttle
. C
heck
th
at
the
re
adin
g is
ze
ro
or
the
rea
bo
uts
. Th
en
turn
st
opco
ck
to b
y-pa
ss
to v
ent
any
furt
her
mer
cury
fu
mes
. D
isas
sem
ble
the
ap
para
tus
and
rin
se
th
e
SnS0
4 p
ort
, th
e stick,
and
the
bo
ttle
th
ree
times
w
ith dis
tilled
Pro
ceed
with
th
e
stan
dard
s an
d un
know
ns
in
the
fore
goin
g
man
ner,
tr
ea
tin
g
the
standard
s in
o
rde
r o
f de
scen
ding
co
nce
ntr
atio
n.
Ave
rage
duplic
ate
ab
sorb
ance
va
lue
s.
If
the so
lutio
n of
an
unkn
own
form
s an
d th
rea
ten
s to
ove
rflo
w,
turn
st
opco
ck
to
by-p
ass
until
the
foam
ing
subsi
des.
A
gain
pa
ss
ca
rrie
r ga
s th
rou
gh
th
e so
lutio
n.
Sw
itch
the
st
opco
ck
back
an
d fo
rth
to
vent
the
mer
cury
up
the h
ood.
D
isas
sem
ble
the
ap
para
tus
as
desc
ribed
in
step 1
3.
Pre
pare
a
seco
nd
ord
er
eq
ua
tion
by
th
e
least
squa
res
met
hod,
p
lott
ing
pg
mer
cury
as
a
bsc
issa
an
d ab
sorb
ance
as
o
rdin
ate
. U
se
the
equatio
n
to
ca
lcu
late
th
e m
ercu
ry c
once
ntr
atio
n
in
mic
rogr
ams
of
the
un
know
ns.
Con
vert
to
pp
m r
emem
berin
g th
at
the
u
nits
o
f pp
m
are
mic
rogr
ams
per
gram
.
13.
The
readin
g o
n th
e
AA c
limb
s to
a
max
imum
whe
re it
paus
es
and
then
de
scen
ds
to
zero
.
14.
If
the
so
lutio
n
thre
ate
ns
ove
rflo
w,
abso
rban
ce
cann
ot
be
de
term
ine
d.
The
sam
ple
and
sta
nd
ard
s m
ust
be
red
on
e.
One
dr
op o
f a
ntif
oa
m
B is
ad
ded
to
both
sa
mpl
e an
d st
an
da
rds
just
befo
re
the
sto
pp
er
is
aff
ixe
d
to
the bottle
.
15.
Dete
ctio
n
lim
it
= 0
.00
5
ppm
. P
erha
ps
the
dete
ctio
n
lim
it
could
be
im
prov
ed if u
ltra
pu
re
aci
ds
wer
e us
ed
Com
pile
d by
M.
Cre
mer
135
REF
EREN
CES
Cas
as,
A.,
and
Vaq
uer,
R
.,
1979
, P
relim
inary
re
su
lts of
mer
cury
in
CR
PG
and
ANRT
ro
ck
and
min
era
l st
andard
s:
Geo
stan
dard
s:
New
sletter,
v.
3,
no.
1,
p.
53
-55
.
ERA
Met
hod
Stu
dy 8
-Ap
pe
nd
ix,
Tota
l m
ercu
ry
in
wate
r:
U.S
. D
ept.
of
Com
mer
ce,
PB
266-
270,
p.
4
7-5
7.
Hat
ch,
W.
R.,
and
Ott
, W
. L
.,
1968
, D
ete
rmin
atio
n
of
sub-
mic
rogr
am q
uantities
of
mer
cury
by
ato
mic
a
bso
rptio
n
spect
rophoto
metr
y:
Anal.
Chem
istr
y,
v.
40,
p.
2085
-208
7.
Hw
ang,
J.
H
., an
d oth
ers
, 19
71,
Dete
rmin
atio
n
of
merc
ury
by
a fla
mele
ss
ato
mic
abso
rptio
n
tech
niq
ue:
Can
adia
n S
pect
rosc
opy,
v.
16
, no
. 4
, p.
2-8
.
Kalb
, G
. W
., 19
70,
The
dete
rmin
atio
n
of
mer
cury
in
w
ater
an
d se
dim
ent
sam
ples
by
fla
mele
ss
atom
ic
abso
rptio
n:
Ato
mic
A
bso
rptio
n
New
sletter,
v.
9,
no.
4,
p.
84
-87
.
Kop
p,
J.
F.,
an
d o
the
rs,
1972
, "C
old
Vap
or"
met
hod
for
de
term
inin
g m
erc
ury
: Jo
urn
al
AWW
A,
Wat
er
Tech
nolo
gy/
Qualit
y,
p.
20-2
5.
Man
ning
, D.
C
.,
1970
, N
on-f
lam
e m
etho
ds
for
mer
cury
de
term
ina
tion
by
ato
mic
abso
rptio
n,
a re
view
: A
tom
ic
Abso
rptio
n
New
sletter,
v.
9,
no.
5,
p.
97
-99
.
__
_1
97
0,
Com
pens
atio
n fo
r br
oad-
band
abso
rptio
n
inte
rfe
ren
ce
in
th
e
flam
ele
ss
atom
ic a
bso
rptio
n
de
term
ina
tion
of
me
rcu
ry:
Ato
mic
A
bso
rptio
n
New
sletter,
v.
9,
no.
5,
p.
109-
110.
Mitte
lhauser,
H
. M
., 19
70,
Mer
cury
an
aly
sis
by f
lam
ele
ss
atom
ic
abso
rptio
n:
Ato
mic
A
bso
rptio
n
New
sletter,
v.
9,
no.
6,
p.
134.
Om
ang,
S.
H
.,
and
Pau
s,
P.
E.,
1971
, T
race
dete
rmin
atio
n
of
mer
cury
in
g
eo
log
ica
l m
ate
rials
by
fla
me
less
at
omic
abso
rptio
n
spe
ctro
sco
py:
A
nal.
Che
mic
a A
cta,
v.
56,
p.
393-
398.
Sig
hin
olfi,
G.
P.,
an
d G
org
oni,
C.,
1980
, A
tom
ic
ab
sorp
tion
dete
rmin
atio
n
of
ultra
trace
elem
ents
in
geolo
gic
al
ma
teria
ls
by v
ap
or,
hyd
ride-f
orm
ing
tech
niq
ue
s.
I M
ercu
ry:
Geo
stan
dard
s N
ew
sletter,
v.
4
, no
. 2,
p.
22
3-22
7.
136
AN
EXTR
ACTI
ON
-
COLO
R M
ET
RIC
PR
OCE
DURE
FO
R M
OLY
BDEN
UM
(A m
odific
ation of
the
proc
edur
e of
B.
F.
Qui
n an
d R.
R.
B
rook
s,
publis
hed
in
An
aly
tica
Chi
mic
a A
cta
74
(1
975)
7
5-8
4,
whi
ch
in
turn
w
as
a m
odific
ation
of
the
pr
oced
ure
of
R.
E.
Sta
nto
n,
pu
blis
he
d
in
the P
roc.
A
ust
. In
st.
Min
. M
et.
, no
. 23
5,
Sep
t. 1
97
0.)
The
pow
dere
d sa
mpl
e is
de
com
pose
d w
ith
HN
03,
HC
104,
an
d H
F;
take
n
to
dry
ness
; an
d b
rou
gh
t up
in
H
C1.
Th
e solu
tion
is
transfe
rred
to
a se
pa
rato
ry
fun
ne
l,
and
shak
en
with
an
asc
orb
ic a
cid
-citric
aci
d
reduci
ng solu
tion.
Sod
ium
io
did
e,
thio
gly
collic
acid
, an
d zi
nc
dith
iol
are
adde
d.
The
solu
tion
is
mix
ed.
The
gree
n m
olyb
denu
m
com
plex
is
extr
acte
d
into
is
oam
yl
ace
tate
, w
ashe
d w
ith
a H
Cl-citric
aci
d so
lutio
n,
and
the
abso
rban
ce
rea
d at
680
nm.
The
pro
cedure
a
llow
s fo
r th
e
de
term
ina
tion
of
0.1
ppm
m
olyb
denu
m.
Rea
gent
s (a
ll
chem
icals
-reagent
gra
de):
Red
ucin
g so
lutio
n.
dis
tilled w
ate
r.P
repa
re
a so
lutio
n
con
tain
ing
15
perc
ent
(w/v
) asc
orb
ic
aci
d
and
2 perc
ent
citric
aci
d
in
Sod
ium
Io
did
e so
lutio
n,
asc
orb
ic
aci
d.
Pre
pare
a
33
perc
ent
(w/v
) solu
tion
of
Nal
in
d
istille
d w
ate
r.
Add
0.5
pe
rce
nt
(w/v
)
Zin
c d
ith
iol
susp
ensi
on.
Add
5 m
l of
eth
anol
to
0.5
g zin
c dithio
l.
Add
3 p
elle
ts
NaOH
(~
1 g
),
5 m
l h^
O,
and
0.5
thio
gly
co
llic
aci
d.
Mix
well
usi
ng
a
stirr
ing
ro
d
to
brea
k up
la
rge
pie
ces
of
zin
c dithio
l,
and
dilu
te
to
100
ml
with
H
20.
The
resultin
g
susp
ensi
on
mus
t be
pr
epar
ed
fresh
d
aily
.
2N h
yd
roch
loric
aci
d -
10
perc
ent
citric
aci
d solu
tion.
Thio
gly
colli
c
aci
d
(~48
p
erc
en
t).
Isoa
myl
ace
tate
.
1000
pp
m m
olyb
denu
m
standard
so
lutio
n.
Dis
solv
e
250
mg
spec
pu
re
mol
ybde
num
po
wde
r in
a
mea
sure
d vo
lum
e of
con
cen
tra
ted
H
N03
. Le
t st
and o
ve
rnig
ht
at
room
te
mp
era
ture
. Ad
d co
nce
ntr
ate
d
HC1
so th
at
the
ra
tio
H
N03
:HC
1 is
is
3:1
. E
vapo
rate
to
d
ryn
ess
. Ta
ke
up w
ith
heat
in
a m
easu
red
volu
me
HC
1.
Co
ol.
Mak
e to
25
0 m
l vo
lum
e w
ith
and
HC1
if
nece
ssary
, so
th
at
the
so
lutio
n
is
20
pe
rce
nt
HC
1.
Pro
cedu
re
1.
Tra
nsf
er
0.50
0 gr
ams
pow
dere
d sa
mpl
e to
te
flo
n
cru
cib
les.
2.
Pre
pare
a
series
of
standard
s 0.0
to
5
.0
ygm
olyb
denu
m b
y tr
an
sfe
rrin
g
each
st
an
da
rd
to
a te
flon
cru
cib
le.
Com
men
ts
137
4. 5.
8. 9.
10.
Add
to
each
cru
cib
le 1
m
l H
ClC
ty,
5 m
l H
N03
, an
d15
m
l HF
. E
vapo
rate
th
e so
lutio
n
to
dryn
ess
on
a hot
pla
te
set
at
ap
pro
xim
ate
ly 1
50°C
.
Add
15
ml
3N
HC
1,
cove
r,
and
heat
a
t 10
0*C
u
ntil
the
salts
ar
e dis
solv
ed.
Tra
nsf
er
the
solu
tion
to
a
60-m
l se
pa
rato
ry f
unnel,
add
1.5
ml
red
uci
ng
solu
tion,
mix
th
oro
ughly
, an
d le
t st
and
for
5 m
inute
s.
3.
Add
3 m
l so
dium
io
did
e so
lutio
n
follo
we
d b
y 0.
05
ml
thio
gly
colli
c aci
d.
Add
1 m
l o
f zi
nc
dithio
l su
spen
sion
, m
ix,
and
let
stan
d fo
r 5
min
ute
s.
Add
5.0
ml
isoa
myl
ace
tate
an
d e
xtr
act
the
gree
n m
olyb
denu
m
com
plex
by
shak
ing
the
separa
tory
fu
nnel
fo
r a
pp
roxi
ma
tely
3
min
utes
. D
rain
an
d d
isca
rd
the
aque
ous
layer.
Was
h th
e is
oam
yl
ace
tate
la
yer
twic
e
(~30
sec
onds
ea
ch)
with
5
ml
po
rtio
ns
of
the H
Cl-citric
aci
d
solu
tion,
and
dis
card
th
e w
ashe
s.
Rin
se
the
tip o
f th
e fu
nnel
w
ith
HzO
, in
surin
g t
hat
the h
^O is
dr
aine
d fr
om
the
tip
com
ple
tely
.
Let
the so
lutio
ns
stan
d fo
r 1/
2 h
ou
r.
Then
dra
in
the
isoa
myl
a
ceta
te
laye
r an
d re
ad
the
abso
rban
ce o
f th
e so
lutio
ns
at
680
nm.
7. 10.
HN03
is
ad
ded
firs
t to
oxi
diz
e
any
org
an
ic m
ate
rial
be
fore
HC
104
com
es
in
conta
ct w
ith it.
Bot
h F
e(I
II)
and
Cu
(II)
fo
rm d
ith
iol
com
plex
es
whi
ch
are
sta
ble
an
d in
solu
ble
in
is
oam
yl
ace
tate
. A
scor
bic
aci
d
redu
ces
Fe(I
II)
and
Cu(I
I)
to
Fe(I
I)
and
Cu(I
) re
spectively
, th
us
pre
ventin
g
cons
umpt
ion
of
dith
iol
by
thes
e el
emen
ts.
The
Fe(I
II)-
dithio
l co
mpl
ex
is bla
ck,
and
the
Cu(I
I)
com
plex
is
pu
rpl i
sh-b
lack.
Citric
aci
d
com
plex
es
tung
sten
w
hich
fo
rms
a blu
e-g
reen
com
plex
w
ith d
ith
iol.
Als
o se
e C
omm
ent
7.
Sodi
um io
did
e
pre
cipita
tes
Cu
(I)
as
grey
cu
prou
s io
did
e.
Th
iog
lyco
llic
aci
d
slow
s th
e ext
ract
ion
of
iod
ine
in
to
the
isoa
myl
ace
tate
.
The
white
collo
idal
susp
ensi
on
whi
ch firs
t fo
rms
is
dithio
l pre
cip
itate
. M
o(V
I)
react
s w
ith
the
dithio
l to
fo
rm a
ye
llow
-gre
en
com
plex
. Th
e st
andin
g
period
shou
ld
be care
fully
tim
ed
in
the
unlik
ely
eve
nt
that
any
tung
sten
ha
s es
cape
d th
e citric a
cid
.
After
the
transf
er
of
the
com
plex
to
th
e is
oam
yl
ace
tate
, th
e
aque
ous
laye
r sh
ould
be
dr
aine
d o
ff,
as
dith
iol
is
slow
ly d
ecom
pose
d oxid
atively
by
iodin
e
as
mor
e io
din
e e
xtr
acts
. E
ventu
ally
the
colo
r o
f th
e
iodin
e itse
lf
caus
es sig
nific
ant
inte
rfere
nce
.
If
the o
rga
nic
la
yer
is
clou
dy
due
to
the
pres
ence
of
disp
erse
d H?
0 dro
ple
ts,
plac
e th
e
sep
ara
tory
fu
nnel
into
hot
H?0
. .,,,..
^ ,
iC-
Com
pile
d by
M.
Cre
mer
13
811
. A
naly
ze
the
data
by
the
met
hod
of
least
sq
uare
s.
K20
AND
Na20
AN
ALYS
IS
(An
unpu
blis
hed
met
hod
devi
sed
by
C.
0.
Inga
mel
ls
and
amen
ded
by
F.
0.
Sim
on
and
J.
H.
Christie)
Pot
assi
um a
nd
sodi
um,
as
the
oxi
de
s,
contr
ibute
su
bsta
ntia
lly t
o
the
sum
mat
ion
in
a cl
ass
ica
l ro
ck
and
min
era
l a
na
lysi
s.
Pot
assi
um m
easu
rem
ents
ar
e us
ed
in
pota
ssiu
m-a
rgon
d
atin
g.1
The
sam
ples
ar
e fu
sed
in
gra
ph
ite
with
Li
862
and
dis
solv
ed
in
4
perc
ent
HN
(H.
Lith
ium
ser
ves
as
an
inte
rnal
stan
dard
fo
r th
e m
easu
rem
ents
w
hich
ar
e m
ade
on
a fla
me
phot
omet
er.2
A
ca
libra
tio
n
curv
e is
ca
lcula
ted
usin
g ro
cks
and
min
era
ls
pre
viousl
y an
alyz
ed
by v
ario
us
prim
ary
met
hods
. In
th
e ab
senc
e o
f co
mplic
atio
ns,
a
pre
cisi
on
of
0.1
perc
ent
abso
lute
an
d a
dete
ctio
n
lim
it o
f 0.
025
perc
ent
K20
are
attain
able
.3
Pro
cedu
re
1.
Base
d up
on
the r
ock
de
scrip
tion
, de
cide
w
heth
er
high
or
lo
w s
tand
ards
ar
e to
be
used
fo
r th
e ca
libra
tio
n
curv
e (s
ee
attach
ed list)
. W
eigh
ea
ch
Sta
ndar
d in
d
up
lica
te.
Com
men
ts
To
exte
nd
the
limite
d
supply
of
stan
dard
s 40
-50
sam
ples
ar
e ru
n at
on
e tim
e.
The
div
isio
n
betw
een
"hig
h"
and
"lo
w"
occu
rs
at
~ 3.0
perc
ent
K20
. A
ll so
dium
ca
libra
tio
n
curv
es
are
calc
ula
ted
from
th
e so
dium
val
ues
acco
mpa
nyin
g th
e
chos
en
K20
sta
nd
ard
s.
Qualit
y co
ntr
ol
sam
ples
ar
e in
clu
de
d
in
each
ru
n.
2.
In
a ta
red
, si
ze
00 b
lack
porc
ela
in
cruci
ble
wei
gh
± 3
mg
sam
ple.
Ad
d 70
0 *
5 m
g of
pure
an
hydr
ous
LiB
02-
Rec
ord
both
sa
mpl
e w
eig
ht
and
tota
l w
eig
ht.
In
th
e sa
me
cru
cib
le,
mix
th
e sa
mpl
e an
d flu
x.
100
2.
Sam
ples
an
d st
anda
rds
are
wei
ghed
on
th
e sa
me
day
beca
use
Li B
O?
is
som
ewha
t hyg
rosc
opic
. Th
e purity
o
f ea
ch
new
batc
h o
f Li
B02
is
ch
ecke
d by
em
issi
on
spec
tres
cop
y.
3.
Bru
sh
the
inte
rio
r o
f a
high
p
urity
g
rap
hite
cr
uci
ble
an
d tr
ansfe
r quantita
tively
th
e m
ixtu
re
to
the
gra
ph
ite cru
cib
le.
Sto
re
sam
ples
an
d st
anda
rds
in
lucite
tr
ays.
The
purity
of
each
ne
w ba
tch
of
gra
ph
ite
cruci
ble
s is
ch
ecke
d by
firing
one
cruci
ble
to
dis
inte
gra
tion
at
1000
°C
in
a p
latin
um
d
ish
. Th
e re
sidue,
if
any,
is
w
eigh
ed
and
anal
yzed
by
em
issi
on
spe
ctro
gra
ph
y.
New
cru
cib
les
mus
t be
ig
nite
d fo
r 2
hour
s at
1000
°C
be
fore
bei
ng
put
into
us
e.
4.
Fuse
th
e co
nte
nts
o
f th
e firs
t six
cr
uci
ble
s at
950°
C
for
15
min
utes
.
Dur
ing
the fu
sio
n,
equi
p six
25
0 m
l tr
ipo
ur
beak
ers
with
dry
1
5/8
inch
K
el-F
mag
netic
stirr
ing
bars
. La
bel
six
card
boar
d co
vers
. Ad
d 10
0 m
l of
4 pe
rcen
t v/
v H
N03
; be
gin
stirr
ing
in
th
e solu
tions,
as
the
time
appr
oach
es
to
rem
ove
the
cru
cib
les
from
th
e13
9
At th
e end
of 15
min
utes
, sl
ight
ly s
wirl
the
red
hot
crucible an
d po
ur the
molt
en bead in
to its
corresponding
beaker.
Place
each emptied
cruc
ible
in
some n
oted o
rder.
Cover
beak
ers
tightly.
Stir
for
ten
minu
tes
whil
e fusing t
he n
ext
lot
of s
ix.
Inspect
the
solutions
for
clar
ity.
6. Cloudy s
olut
ions
ma
y co
ntai
n so
me reducible
element;
a dr
op o
f 30 p
ercent h^f^,
usua
lly
caus
es the
solution to clear.
7. Inspect
each
cool graphite cr
ucib
le f
or a
dhering
particles.
7. Adhering p
articles,
if a
ny,
must
be
dug
out
with a
stai
nles
s steel
spatula
and
added
to th
e ap
prop
riat
e beaker.
If th
is is
no
t fe
asib
le,
a ne
w po
rtio
n mu
st
be f
used o
n an
othe
r da
y.
(See comment
2)
8. Repeat th
e above
proc
edur
e for
all
samples.
9. Use
the
auto
mati
c diluter
to dilute sa
mple
s 1
to 10
, with distilled
h^O
dispensing in
to small
15 m
l plastic
beak
ers.
9. Th
e di
luti
on ne
ed no
t be e
xactly 1
:10
but
it m
ust
be
the
same for
all
solu
tion
s.
10.
On flame
photometer,
turn on
both the
prop
ane
gas
and
air
completely,
in th
at or
der.
11.
Depress
power
(flame w
ill
auto
mati
call
y ignite).
Allo
w 45
minutes fo
r wa
rm u
p.
12.
Continually
aspirate h^O
duri
ng w
armu
p.
For
5mi
nute
s du
ring
the
war
mup,
aspirate a
dil
ute
solution
of r
econstituted n
orma
l human
blood
seru
m.
(1 dr
op p
er 2
5 ml
12.
The
blood
seru
m pr
otei
n coats
the
spray
chamber
to
minimize formation
of w
ater droplets on the
cham
ber
walls.
Undi
lute
d se
rum
is ke
pt refrigerated.
13.
Befo
re o
perating w
ith
rock solutions, check
that
th
e as
pira
tion
rate
is approximately
40 s
econds/ml.
140
14.
On
the
D
igital
Prin
ter
pres
s re
se
t to
se
t th
e
sequentia
l co
unte
r to
00
1.
Dep
ress
AD
VANC
E to
p
ositio
n
the
paper.
15.
For
K£0
analy
sis
, asp
irate
S
ierr
a Q
ua
rtz.
A
dju
st
the
signal
dis
pla
y
on
the
lit
hiu
m r
espo
nse
met
er
so
that
the
red
ne
edle
co
mes
to
re
st
opposi
te
the
b
lack
tr
iangle
be
twee
n th
e h
orizonta
l b
lack
lin
es.
Set
th
e
dig
ital
conce
ntr
atio
n
dis
pla
y to
ze
ro w
ith
the
kno
b on
th
e le
ft
sid
e o
f th
e in
stru
ment.
16.
Asp
irate
th
e h
igh
est
1^
0 st
andard
. C
heck
th
elit
hiu
m r
espo
nse
and
adju
st if
ne
cess
ary
. U
sing
th
e
dia
l a
t th
e le
ft o
f th
e dis
pla
y.
Set
th
e d
igita
l co
nce
ntr
atio
n
to
< 28
0.0
(hig
h
scale
) or
<
28.0
(lo
w
- sc
ale
) w
hich
ever
is
applic
able
.
16.
The
bla
ck
switc
h
to
the r
igh
t of
the
dis
pla
y activate
s
the
hig
h
and
low
sc
ale
. Th
e settin
g
chos
en
for
the
hig
h
standard
is
a
rbitra
ry.
The
settin
gs
sugg
este
d he
re
allo
w fo
r in
stru
ment
drift
sin
ce
the
fu
ll
span
is
0
to
280.0
or
0 to
2
8.0
. Th
e de
cim
al
poin
t ap
pear
s be
twee
n th
e
seco
nd
and
third
d
igit
(e.g
. 17
.00
for
1.70
p
erc
en
t 1^0
);
on
the
hig
h
sca
le it
appe
ars
betw
een
the th
ird
an
d fo
urt
h d
igit
(01
7.0
).
17.
Ifha
s a
lso
be
en
request
ed,
repeat
step
15.
18.
Asp
ira
te
the
h
igh
est
N
a?0
sta
nd
ard
an
d sw
itch
to
lo
w
sca
le
beca
use
Na2
0 is
al
way
s ru
n on
th
at
sca
le.
Che
ck
lithiu
m
as
be
fore
an
d se
t th
e
perc
ent
Na2
0 on
th
e dig
ital
dis
pla
y.
The
deci
mal
poin
t ap
pear
s be
twee
n th
e 3
rd
and
4th
dig
it.
19.
Asp
ira
te
standard
s an
d un
know
ns
in
the
follo
win
g
ord
er,
depre
ssin
g
DATA
whe
n th
e d
isp
lay n
o lo
ng
er
chan
ges,
u
su
ally
after
8-1
0
seco
nds.
A
ll solu
tions
mus
t be
rea
d in
th
e
sam
e m
anne
r.
Typ
ica
l aspiration
ord
er:
a.
duplic
ate
st
andard
sb
. 6
unkn
owns
c.
du
plic
ate
st
andard
sd
. th
e
sam
e 6
unkn
owns
e.
duplic
ate
st
an
da
rds
19.
Drift
re
spon
se
is
inhere
nt
in
the
o
pe
ratio
n
of
the
fla
me
photo
mete
r.
Fre
quen
t a
sp
ira
tio
n
of
sta
nd
ard
s to
bra
cket
unkn
owns
m
inim
ize
s err
ors
in
troduce
d
by
inst
rum
en
tal
drift.
A se
t of
sta
nd
ard
s an
d un
know
ns
should
n
ot
exce
ed
ten
of
each
.
141
20.
Con
tinue
th
e o
pe
ratio
n
until
all
unkn
owns
ha
ve
been
ru
n.
The
data
colle
cte
d
from
19
a an
d c
abov
e is
w
eig
ht
corr
ect
ed
an
d us
ed
to
pre
pare
a
line
ar
reg
ress
ion
. Fr
om th
is
slo
pe-inte
rcept
eq
ua
tion
th
e
con
cen
tra
tion
of
the
un
know
ns
in
19b
is
calc
ula
ted
and
weig
ht
corr
ect
ed.
Dat
a fr
om
19c,
d
, an
d e
are
treate
d
in
the s
ame
man
ner.
Th
e re
port
ed va
lue
is
the
av
erag
e of
the
two
calc
ula
ted
va
lue
s.
Com
pile
d by
M.
Cre
mer
REFE
RENC
ES
1.
Pot
assi
um-A
rgon
D
atin
g,
G.
Bre
nt
Da
lryn
ple
an
d M
arvi
n A.
La
nphe
re,
pp
27
-51
.
2.
Ope
rato
rs
Man
ual
IL
343
Dig
ital
Flam
e P
hoto
met
er
and
2064
2 S
ampl
e C
hang
er
and
Dig
ita
l P
rinte
r
3.
The
Alk
ali
Me
tals
, P
art
II,
V01
. 1
of
Tre
atise
on
A
naly
tical
Chem
istr
y ed
s.
I.M
. K
olthoff
and
P.
J.
Elv
ing,
pp
378-3
88.
142
DIVISION OF ROCKS INTO HIGH AND LOW % K20
LOW'S - % K?0 3.0%
Actinolite
Alunite; Both high and low, 2-8%
Amphibole
Andesite
Basalt
Biotite-Camptonite; 2.5%
Caliche (very difficult)
Camptonite
Chlorite
Dacite; Both high and low y 2-4%
Gabbro
Granite
Greenstone
Hornblende
Metagraywacke
Plagioclase
Pumice
Quartz
Quartz-Sericite; Both high and low, 1-6%
Riebeckite
Soil Carbonates
Whole Rock
HIGH'S - % K?0 3.0%
Adularia (generally)
Alunite; Both high and low, 2-8%
Biotite
Dacite; Both high and low, 2-4%
Feldspar; (alkali; K-Feldspar, generally)
Felsite; 4-6%
Glauconite
Glaucophane; Both high and low, see amphibole.
Granodiorite; Both high and low 2-7%
Monzonite: Both high and low, 2-6%
Muscovite; Both high and low, to 7%
Obsidian; (generally)
Orthoclase; ?
Perlite; 5%
Phlogophite
Phyllite
Quartz-Sericite; Both high and low
Rhyolite; ? Both high and low?
Sam" dine; 13%
Sericite; 0.5-5%
Syenite; 4%
White Mica
CO
MIC
RO
CO
ULO
MET
RIC
M
EASU
REM
ENT
OF
WAT
ER
IN
MIN
ER
ALS
Whe
n sa
mpl
e q
ua
ntity
is
a
prob
lem
, to
tal
wat
er
is
dete
rmin
ed
on
50 m
g or
less
u
sin
g
the
Dup
ont
Mo
istu
re
An
aly
zer
whi
ch
has
been
m
od
ifie
d
to
acco
mm
odat
e deco
mposi
tion
outs
ide
the
in
stru
ment.
Nitr
og
en
ga
s ca
rrie
s
the w
ate
r fr
om
the
melte
d
sam
ple
and
flu
x
in
the
com
bust
ion
tube
to
th
e e
lectr
oly
tic cell.
The
ce
ll cu
rre
nt
inte
gra
tin
g
syst
em
is
ca
libra
ted
to
re
ad d
ire
ctly
in
mic
rogr
ams.
Th
e re
act
ion
in
the cell
is:
P20
5 +
H20(
g)
> P2
05
-H20
>
P20
5 +
H2(g
) +
1/2
0
2(g
).
Rea
gent
s (a
ll
chem
icals
-reagent
gra
de):
Cal
cium
ca
rbonate
po
wde
r.
Ko
fbl
com
bust
ion
cata
lyst
(silve
r pe
rman
gana
te
de
com
po
sitio
n
pro
duct
) e
ith
er
purc
hase
d o
r pr
epar
ed
from
pota
ssiu
m
perm
anga
nate
an
d silv
er
nitra
te.
Lead
oxi
de
yello
w
(low
silver)
po
wde
r,
lead
ch
rom
ate
pow
der,
an
d co
pper
oxi
de
pow
der.
App
arat
us:
A m
odifi
ed
Dup
ont
Type
26
-321
A-M
A M
ois
ture
A
na
lyze
r.
Dry
cylin
der
nitr
og
en
(9
9.99
5 perc
ent
pu
rity
, de
w poin
t -
90°F
).
Two
so
lid a
cry
lic
purg
e m
eter
s (f
low
mete
r),
Mat
heso
n S
erie
s 20
1.
Larg
e C
aS04
d
ryin
g tu
be.
U tu
be filled w
ith
mag
nesi
um p
erc
hlo
rate
(a
.k.a
. a
nh
ydro
ne
).
Sto
pcoc
k g
rea
se,
no
t hig
h
vacu
um.
Vyc
or
mic
roco
mbu
stio
n tu
be w
ith
bent
ca
pill
ary
sid
e
arm
.
Te
flon
tu
bin
g.
Sili
ca
wo
ol.
Micr
o co
mbus
tion
fu
rnac
e co
ntro
lled
by
a variable tr
ansf
orme
r.
Coors
no.
00 porcelain
boats.
Alum
inum
tray
to h
old
Coor
s boats.
14
4
Sili
con
stop
per.
Pro
cedu
reC
omm
ent
1.
Cle
an
in
the
usua
l m
anne
r an
d th
en ig
nite
Coo
rs
1.
No.
00
p
orc
ela
in
boat
s fo
r 1/
2 ho
ur
at
1000
°C.
Sto
re
in
a desic
cato
r.
Aft
er
choosi
ng th
e
com
bust
ion
tub
e,
test
each
boat
for
fit.
2.
Cle
an
com
bust
ion
tube
in
the
us
ual
man
ner.
Do
n
ot
hand
le w
ith
bare
ha
nds.
D
ry o
vern
igh
t at
105°
C.
3.
Pre
pare
a
10
+ 1
+ 1
PbO
iPbC
rO^C
uO f
lux
byin
tima
te
mix
ing
and
ign
itio
n fo
r 30
min
a
t 40
0°C
. S
tore
in
d
esic
ca
tor.
4.
Dry
the
KbY
bl
com
bust
ion
oca
taly
st
and
the
C
aC03
fo
r 4.
se
vera
l ho
urs
at
105
± 5°
C.
Add
to
the
com
bust
ion
tube
a
plu
g o
f silic
a
wo
ol-K
orb
l co
mbu
stio
n cata
lyst-
silic
a w
ool-ca
lciu
m carb
onate
-sili
ca
woo
l a
few
in
ches
fr
om
the
redu
ced
end.
5.
Pla
ce
the
co
mbu
stio
n tu
be
in
a ra
ck
ho
ldin
g
a 5.
com
bust
ion
furn
ace
to
w
hich
a
Va
ria
c is
attach
ed.
Rai
se
or
low
er
the
com
bust
ion
tube
in
th
e
rack
so
th
at
it
is
cente
red w
ithin
th
e
furn
ace
el
emen
t. Th
en
mak
e th
e fo
llow
ing
co
nnect
ions:
Nitr
ogen
tan
k »
tygo
n tu
bin
g
» flo
w m
eter
»
tygo
n tu
bin
g
> D
rie
rite
»
tygo
n tu
bin
g
» m
agne
sium
perc
hlo
rate
in
U
tube
»
tygo
n tu
bin
g
» m
ois
ture
analy
zer
» te
flon
tub
ing
>
com
bust
ion
tube
»
teflon
tubin
g
> m
ois
ture
analy
zer
oven
»
teflon
tub
ing
>
ce
ll »
late
x
tub
ing
»
flow
m
ete
r.
6.
Set
th
e deliv
ery
pre
ssu
re
on
the re
gula
tor
to
~5
psi
q.
With
th
e
mete
ring va
lve,
set
the
flow
to
-0
.05-0
.06
SCFH
air.
7.
Inse
rt
an
exha
uste
d cell
in
the ce
ll ca
se
and
chec
k 7.
th
e flo
wm
ete
r at
lin
e's
en
d.
2.
Fin
ge
rprin
ts
on
heat
ed
qu
art
z ha
sten
d
evitrifica
tio
n
The
Korb
l co
mbu
stio
n ca
taly
st
insu
res
the
oxid
ation
of
org
anic
co
mpo
unds
an
d hyd
rogen.
Cal
cium
ca
rbo
na
te
abso
rbs
aci
d
gase
s w
hich
o
the
rwis
e
corr
ode
the
tub
ing
an
d flo
w co
ntr
ol.
The
nitr
og
en
ta
nk
sho
uld
be
eq
uipp
ed w
ith
a re
gula
tor
and
me
terin
g va
lve.
Non
e of
the
tu
bin
g
sho
uld
be
u
nn
ece
ssa
rily
lo
ng.
The
con
ne
ctin
g tu
bin
g a
t th
e
back
of
the
mois
ture
analy
zer
shou
ld
be
as
sho
rt
as
po
ssib
le;
i.e.
the
p
yre
x outlet
from
the
U tu
be
shou
ld
exte
nd
into
th
e m
etal
in
let
ho
le
on
the
mois
ture
a
na
lyze
r.
The
jun
ctio
n
is
secu
red
with
a
clam
p ar
ound
a
pie
ce of
tyg
on
tu
bin
g w
hich
is
sc
rew
ed
onto
th
e m
ois
ture
analy
zer
thre
ad
s.
The
flow
mete
r sh
ould
re
ad
ap
pro
xim
ate
ly t
he
sam
e as
th
e
entr
ance
flo
wm
ete
r.
If it
does
re
ad
too
low
or
not
at
all,
the
who
le
syst
em
mus
t be
ch
ecke
d fo
r le
aks
usi
ng
Sno
op solu
tion.
If
no
leaks
ap
pear
, th
en
the
capill
ary
in
th
e ce
ll is
b
lock
ed
; a
no
the
r ce
llsh
ould
be
in
sert
ed.
145
8.
Whe
n th
e
syst
em
is
leak
fr
ee
, pu
rge
with
N2
fo
r ~1
5 m
inut
es
or
longer.
In
sta
ll
a fu
nctionin
g
cell
and
agai
n dry
th
e
syst
em fo
r an
ho
ur
or
un
til
the
zero
a
dju
st
contr
ol
can
be
set
so
the
coun
t ra
te fa
lls
betw
een
15
counts
/15
seco
nds
and
45
counts
/15
seco
nds
9.
Attach
a
reco
rde
r to
th
e m
ois
ture
analy
zer.
10.
Eac
h m
orn
ing,
or
aft
er
a le
ng
thy
inte
rruption,
burn
out
the
sy
stem
by
he
atin
g
the rig
ht
sid
e o
f th
e
com
bust
ion
tube
to
~11
00
C by
tu
rnin
g
the
V
aria
c to
~1
35.
At
the
sam
e tim
e,
turn
th
e
timer
on
the
mo
istu
re
an
aly
zer
to
one
hour.
8.
See
para
grap
h 2
-8,
p.
2-2
, O
pe
ratio
n
and
Mai
nten
ance
M
anua
l, Ty
pe
26
-32
1A
-Mo
istu
re
Analy
zer.
W
ith
the
time
r off,
pres
s an
d hold
do
wn
the
ze
ro
pu
shb
utt
on
to
a
dju
st
the
co
unt
with
th
e
knob
at
the right.
9.
It
is
help
ful
to fo
llow
ce
ll pe
rfor
man
ce w
ith
a re
cord
er.
10.
Mo
istu
re build
up
can
occ
ur
over
an
in
active
period o
f ab
out
an
hour.
Th
e m
ois
ture
a
na
lyze
r is
se
t so
th
at
the
te
mp
era
ture
with
in its
oven
is
~4
50°C
. Th
e V
ariac
has
been
ca
libra
ted
again
st
the
tem
pe
ratu
re
in
the
co
mbu
stio
n tu
be
.
11.
Aft
er
15
min
ute
s,
turn
th
e V
ariac
to
65
and
allo
w
the
11
furn
ace
to
co
ol
~8-
10 m
inute
s.
Then
m
ove
it
ove
r th
e
plu
g o
f co
mpo
unds
.
12.
Whe
n th
e
cou
nt
subs
ides
to
~1
count/6
sec.
, tu
rn off
12.
the
timer
and
the
Variac.
O
r, if
pre
ferr
ed
, w
hen
reco
rder
tra
ce ta
ils o
ff
and
countin
g
slow
s m
easu
reably
, an
arb
itra
ry lin
e
on
the
trace
ca
n be
ch
osen
fo
r tu
rnoff.
This
lin
e
is
then
us
ed
in all
subs
eque
nt opera
tions.
13.
Wh
ile w
aitin
g fo
r th
e m
ois
ture
a
na
lyze
r to
co
mpl
ete
13.
its
cycl
e a
fte
r tu
rnoff,
chec
k in
stru
ment
and
ce
ll pe
rfor
man
ce
as
follo
ws:
Cho
ose
as
a st
andard
a
pure
m
inera
l w
hose
w
ate
r co
nte
nt
has
been
d
ete
rmin
ed
by
the P
en
field
m
etho
d.
Acc
ura
tely
wei
gh
a boat,
rem
ove
it
from
th
e
bala
nce
to
the
sm
all
alum
inum
tr
ay,
and
fill
the
bo
at w
ith
~50
mg
of
the m
inera
l. U
se
<50
mg
if
the
w
ate
r co
nte
nt
is
>5
perc
ent.
Rew
eigh
bo
at
and
sam
ple.
The
tem
pera
ture
sh
ou
ld
have
co
oled
to
~4
50°C
in
th
e
10
-min
ute
in
terv
al.
The
tem
pe
ratu
re
was
a
rbitra
rily
ch
osen
to
drive all
1^0
forw
ard
w
ithout
deco
mpo
sing
or
m
elti
ng
th
e co
mpo
unds
.
At
this
tim
e,
the
mo
istu
re
analy
zer
oven
re
turn
s
to
ambi
ent
tem
pe
ratu
re,
and
the
red
pro
cee
din
g lig
ht
goes
out.
The
analy
zer
is
now
ready
to
acce
pt
a b
lan
k or
sam
ple.
So th
at
the
dete
rmin
atio
n
can
be m
ade
in
a fin
ite
tim
e,
a re
ad
ou
t of
~200
0 to
30
00
ng
wate
r sh
ould
n
ot
be
exce
eded
, if possib
le.
146
14.
Rem
ove
boat
an
d sa
mpl
e an
d ag
ain
pla
ce
in
alum
inum
tr
ay.
Fill
boat
w
ith flux
eve
nly
dis
trib
ute
d
and
rew
eig
h.
15.
Pla
ce
the
boat
in
the
com
bust
ion
tube
near
th
e r
ight;
cen
ter
the
furn
ace
ar
ound
it,
and
turn
th
e V
aria
c to
13
5.
At
the
sa
me
time
, tu
rn
the
timer
to
one
hour.
16.
At
the
end
of
15
min
ute
s,
turn
th
e V
ariac
to
65
and
allo
w
8-10
min
utes
coolin
g.
17.
Then
m
ove
the
furn
ace
all
the
way
to
th
e le
ft o
f th
e
rack
ar
ound
th
e
com
poun
ds.
18.
Whe
n th
e
coun
t m
atch
es
tha
t of
step
12,
turn
o
ff
the
timer
and
the
V
ariac.
R
ecor
d yg
of
wate
r.
19.
In
the
sa
me
man
ner,
w
eigh
flu
x
on
ly to
be
us
ed
as
a b
lan
k.
Rep
eat
steps
15-1
8.
Rec
ord
pQ w
ater
an
d calc
ula
te
the
bla
nk
as
pe
rce
nt
1^0:
(y
g 1^
0)
(100
perc
ent)
/wt
in
gram
s x
10^.
20.
Ca
lcu
late
p
erc
en
t w
ater
in
th
e
sam
ple
as
follo
ws:
% H2
0 -
j(Mg
H20
ml.n
era
l)
- (%
H2
0 b
lan
k x
flux w
t.
in
gram
s m
ine
ral
x 10
^ ^9 gr
am
21.
Repeat the
determination
twice
more.
22.
Determine
H20
in the
unkn
owns
in
th
e sa
me m
anne
r.
23.
Soak used b
oats
in
concentrated HC1
for
three
weeks.
Scrape the
boats
and
leac
h th
em i
n di
stil
led
H20
until
needed.
24.
To shut do
wn the
system,
remo
ve t
he c
ell,
cap
it,
and
stor
e it in a
desi
ccat
or.
To b
leed th
e N2
> re
move
th
e st
oppe
r next to
th
e ba
ck o
f th
e moisture
anal
yzer
. Replace
the
stop
per
when th
e regulator
reads
zero
.
14.
Fill
ing
the
boat w
ith
flux u
sual
ly r
esults in an
~10
to 1
rati
o flux t
o sa
mple
.
16.
Duri
ng t
his
period,
a pattern
of p
eaks appears
on th
e re
cord
er paper
which
diff
ers
with m
ineral ty
pe,
amount o
f samp
le an
d fl
ux,
amou
nt o
f pa
ckin
g in
combustion tu
be,
etc.
17.
Now
the
major
peak
ap
pear
s th
at w
ater trapped
by t
he
comp
ound
s.
18.
The
recorder pe
n will now
be b
ack
at it
s be
ginn
ing
position.
19.
The
blank
is us
uall
y _<
-.03
per
cent
HgO.
mine
ral
21.
Resu
lts
should agree
to approx.
±1 percent
with ea
ch
other
and
with th
e Pe
nfie
ld number.
23.
The
substances in the
boat
s ar
e converted
to c
hlorides,
24.
The
gas
is bled slowly s
o that particles
are
not
blown
into
the
flow s
ystem.
147
25.
To
reco
at
a cell,
pass
ac
eton
e an
d d
istille
d
H20
thro
ugh
the
cell
part
s th
ree
times
a
lte
rna
tive
ly.
Fin
ish
with
ac
eton
e.
Pre
pare
an
8
-pa
rt
acet
one
to
a 2-p
art
H
3P04
m
ixtu
re.
Pass
2
ml
thro
ugh
the
cell.
To
conve
rt
the
mix
ture
to
P2
0s»
conn
ect
the
cell
to
the
syst
em.
Turn
th
e m
ois
ture
an
alyz
er
to
one
hour
an
d pu
rge
with
dry
N£
« Th
e pr
oces
s,
acc
ord
ing
to
D
upon
t, m
ay
take
fr
om 1
5 to
45
min
utes
,
Com
pile
d by
M.
Cre
mer
148
REFE
RENC
ES
Co
nso
lida
ted
E
lect
rod
yna
mic
s C
orp
ora
tio
n,
Jan.
1955
, (C
EC
sub
seq
ue
ntly
ta
ken
o
ver
by
Du
po
nt)
, O
pe
ratio
n
and
Ma
inte
na
nce
M
an
ua
l, Ty
pe
26-3
21A
M
ois
ture
A
na
lyze
r.
Cre
mer
, M
., an
d oth
ers
, 19
72,
Mic
roco
ulo
me
tric
m
easu
rem
ent
of
wate
r in
m
ine
rals
: A
na
l.
Chi
m.
Act
a,
v.
60
, p.
18
3-1
92
. 149