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UCRL 7167 Rev. I
University of California
Ernest O. Lawrence Radiation Laboratory
THE VAPOR PRESSURES OF
30 INORGANIC LIQUIDS BETWEEN ONE
ATMOSPHERE AND THE CRITICAL POINT
Livermore, California
DISCLAIMER
This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency Thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.
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UCRL-7167 Rev. I
UNIVERSITY OF CALIFORNIA
Lawrence Radiation Labora tory
L ive rmore , California
Contract No. W-7405-eng-48
THE VAPOR PRESSURES OF 30 INORGANIC LIQUIDS BETWEEN
ONE ATMOSPHERE AND THE CRITICAL POINT
DAVID G. EDWARDS
June 17, 1964
0
CONTENTS
Abs t rac t . . . . . . . . .
Introduction . . . . . . . .
A. Vapor P r e s s u r e Deviations from the Claus ius-Clapeyron Equation . . . .
B. Exper imenta l Data
C. Scope of this Work
Vapor P r e s s u r e Deviation Curves
A. Construction of Deviation Curves
B. Shape of Curves
C. Slope of Curve at Normal Boiling Point
D. Relation to Liquid and Vapor Densi t ies Along Coexis tence Envelope . . . . . .
E. Correspondence of Maxima and Minima
F . Correspondence of Data with Deviation Curve
Deviation Curves and Tables of Interpolated Vapor P r e s s u r e s
A. P rocedure . . . . . . . .
B. Summarized Cr i t ica l P rope r ty and Vapor P r e s s u r e Values
C. Individual Substances
1. Hydrogen Isotopes
2. Neon
3. Nitrogen
4. Carbon Monoxide
5. Argon
6. Oxygen
7. Methane
8. Nitric Oxide
9. Krypton
- i i i -
CONTENTS (Continued)
10. Xenon
11. Silicon Tetrafluoride
12. Ni t rous Oxide
13. Carbon Dioxide
14. Hydrogen Chloride
15. Hydrogen Bromide
16. Sulfur Hexafluoride
17. Hydrogen Sulfide
18. Hydrogen Iodide
19- Chlorine
20. Ammonia
21. Cyanogen
22. Sulfur Dioxide
23. Hydrogen Fluor ide
24. Hydrogen Cyanide
25. Nitrogen Tetroxide
26. Bromine
27. Sulfur Trioxide
28. Carbon Tet rachlor ide
29. Tin Tet rachlor ide
30. Water
IV. Acknowledgments
V. References
- I V -
- 1 -
THE VAPOR PRESSURES OF 30 INORGANIC LIQUIDS BETWEEN
ONE ATMOSPHERE AND THE CRITICAL POINT*
DAVID G. EDWARDS
Lawrence Radiation Laboratory , Universi ty of California
L ive rmore , California
June 17, 1964
ABSTRACT
Li te ra tu re values of the vapor p r e s s u r e s of H , HD, D^, N^, O^, Ne,
Ar, K r , Xe, CO, NO, CH^, SiF^, N^O, CO^, HCl, HBr, HI, SF^, H^S, Cl^.
Br^ , NH^, C^N , SO^, SO^, HF, HON, N^O^, CCl , and SnCl have been
compared with the Kirchhoff formula
log PT^ = - A / T + B is.
between the normal boiling point and the cr i t ica l point, where A and B are de
te rmined for each liquid. Plots a re presented of the deviations computed by
the equation
K obs
Based on accura te ly de termined curves for 17 of these subs tances , e m
pi r ica l hypotheses were developed to allow the predict ion of the most probable
course of the deviation curve in ca ses where the data appeared to be unre l i
able . In addition, where p rec i se data were avai lable, the possibi l i ty of the
existence of f ine-s t ruc ture curvature has been demons t ra ted .
Work performed under the auspices of the U. S. Atomic Energy
Commission.
- 2 -
The deviation curves have been used to obtain tables of interpolated
vapor -p ressu re values which a r e , in most c a s e s , more accura te by one order
of magnitude than any now in the l i t e r a tu re , par t icu lar ly where smoothed
r e g r e s s i o n curves do not d i sc r imina te between random exper imenta l e r r o r s
and systemat ic deviations of an a r b i t r a r i l y chosen formula from the r ea l
v a p o r - p r e s s u r e curve . Since the deviation curve is invariably shown to
approach the ze ro ordinate at the cr i t ica l point with a large negative slope,
the correspondence between the cr i t ica l p r e s s u r e and t empera tu re is fixed
with a high degree of confidence. A par t icu lar resu l t of this work is that
the cr i t ica l p r e s s u r e of NH_ was shown to be about one a tmosphere higher
than the present ly accepted value. Our values for the cr i t ica l points of
CH. , C^N^, HCN, and Br^ have also resolved differences existing between
var ious author i t ies in the l i t e r a tu re .
I. INTRODUCTION
A. VAPOR PRESSURE DEVIATIONS FROM THE CLAUSIUS-
CLAPEYRON EQUATION
The approximate Claus ius-Clapeyron re la t ion (Eq. 3 below) predic ts
that the log of the vapor p r e s s u r e P should vary l inear ly with the inverse of
the absolute t empera tu re T. Actually, the rea l vapor p r e s s u r e deviates
from this re la t ionship , as shown in exaggerated form in Figure 1. The
origin of these deviations can be seen from a considerat ion of the exact
Claus ius-Clapeyron equation
dP/dT= A H / T (V - V ), (1)
where AH is the heat of vaporization at t empera tu re T, and V and V. a re g i
the vapor and liquid molar volumes, respect ive ly . At p r e s s u r e s below one
a tmosphere , V is substantial ly ze ro and V is given quite closely by the
ideal gas equation
V = R T / P . (2) g
Substituting Eq. 2 into 1, the famil iar form of the approximate Claus ius-Clapeyron
equation is obtained:
A H / R r e p r e s e n t s the slope of the line given by a plot of In P vs 1 / T . The
major deviation of the rea l vapor p r e s s u r e from this line below the boiling
point or iginates from the fact that AH is not a constant but va r i e s with T
according to a re la t ion such as Eq. 4:
AH = a + bT + cT^, (4)
where a, b , and c a r e constants . As T approaches the c r i t i ca l point, AH
goes to ze ro ; and above one a tmosphere , the deviation of V from the ideal
- 4 -
O
Crit ical point
nflection point
Boiling point
Tr ip le point
/T GLL-63ij--T25A
F i g . 1. The log P vs 1/T v a p o r - p r e s s u r e c u r v e e x a g g e r a t e d to show the v a r i o u s c u r v a t u r e s . (Adapted with p e r m i s s i o n f r o m I n d u s t r i a l and E n g i n e e r i n g C h e m i s t r y . )
- 5 -
gas equation becomes p rogress ive ly g rea t e r ; V also begins to increase
significantly. At the cr i t ica l point AV becomes ze ro ; although AH/AV is
indeterminate at the cr i t ica l point, it has a l imiting value of approximately
7P (111), c
Returning to an examination of Eq. I, it is seen that the inflection
point (shown between the boiling point and the cr i t ica l t empera tu re in F igure
1) a r i s e s from the necess i ty that the dew point line of the coexistence
envelope change di rect ion in order to attain c losure at the cr i t ica l point.
This general ly occurs for T / T between 0.75 and 0.85.
Thus the deviations of vapor p r e s s u r e from ideal behavior a r e seen to
be due to:
(1) Depar ture of dAH/dT from l inear i ty .
(2) Deviation of V from ideal behavior . g
(3) An inflection point in (dV /dT) at the saturated condition
(denoted by the subscr ipt s) .
Although the v a p o r - p r e s s u r e - t e m p e r a t u r e re la t ionship could be exactly
expressed by substituting a power s e r i e s in T for AH, and a power s e r i e s in
( 1 / T ) P for AV (as d iscussed by Lewis and Randall (66)), it has been shown by
Waring (111) that a four-constant equation of the form
log P = A + B / T + C T + DT^ (5)
is adequate to descr ibe the features of the rea l v a p o r - p r e s s u r e curve
i l lus t ra ted in Figure 1. Indeed, Miller (78) has shown that for the region be
tween one a tmosphere and the cr i t ica l point, which is the a r e a of in teres t in
this investigation, Eq. 5 could be fitted to the data for 23 of the compounds
given by this work to within 1.54% average ma^ximum e r r o r . F u r t h e r m o r e ,
according to Miller , even the simple Kirchhoff equation
log P =: - A / T + B (6)
- 6 -
(where A and B a re constants) fitted the same data with an average maximum
e r r o r of only 3.20%. This close fit between the boiling point and the cr i t ica l
point is a consequence of the fact that for many substances a line of constant
slope drawn between the boiling point and the cr i t ica l point b i sec ts the rea l
v a p o r - p r e s s u r e curve because of the existence of the inflection d i scussed
above. In addition, it develops that the slope A in Eq. 6 i s , for many of the
substances investigated he r e , quite close to the slope at the boiling point, as
is shown in Table I below; the a r i thmet ic sum of the maxinnum positive and
negative deviations of the vapor p r e s s u r e from Eq. 6 for these substances is
about 1 atm. or l e s s , as is seen in F igures 2-5 below. The derivat ion of the
modified Klein equation for predicting heats of vaporization (102) was based
on a recognit ion of this condition.
Thus it is seen that while Eq. 5 adequately follows the rea l vapor-
p r e s s u r e curve, it may be in e r r o r by as much as 1.5% when the constants a re
derived from a corre la t ion using T , P , and T (as shown by Miller (78)),
or by a few tenths of a percent if fitted by a r e g r e s s i o n curve to the exper imenta l
v a p o r - p r e s s u r e data between T and T , as done by many of the authors cited
in this work. For cr i t ica l p r e s s u r e s of 40 to 60 a tm. , e r r o r s of 1.5% amount
to absolute e r r o r s of 0.6 to 0.8 a tm. Even when fitted by r eg res s ion - l ine
t r ea tment , the result ing equation fails markedly to fit the data to the same
degree as the precis ion of the measu remen t s in the region of high curvature
between the inflection point and the cr i t ica l point. This situation has been
graphical ly demonst ra ted by Michels et_al. (73-77). F u r t h e r m o r e , F r i edman
and White (31) have specifically stated that Eq. 5 cannot be made to give a
good fit with the data for N- near both the boiling point and the cr i t ica l point.
This also has been recognized by Hoge (50), who fitted the data for oxygen
to five separate equations of the type of Eq. 6, and by Osborne et a.1. (85, 86),
- 7 -
T A B L E I
COMPARISON O F H E A T S O F V A P O R I Z A T I O N
S u b s t a n c e
n - H ^
Ne
^ 2 CO
A r
^ 2 CH^
NO
Kr
Xe
S i F ^
N^O
HCl
H B r
5 ^ 6 H^S
HI
^^2 NH3
^ 2 ^ 2 SO2
(HF)^
HCN
^ 2 ^ 4
B^2 SO3
CCI4
SnCl^
H^O
AH^
c a l . / m o l e
216
410
1333
1444
1558
1630
1955
3293
2158
3021
4460
3956
3860
4210
4080
4463
4724
4878
5581
5576
5955
5020^
6027
7040^
7030
9990
7170
8300
9717
AH, k c a l . / m o l e
258
442
1353
1446
1546
1631
1985
2988
2153
2995
3945
3768
3799
4090
3992
4285
4 6 0 1
4675
5340
5342
5677
6422
6478
8203
6826
7639
6918
7794
9147
^ ^ k - ^ ^ b c a l . / m o l e
42
32
20
2
-12
1
30
- 3 0 5
- 5
-26
- 5 1 5
- 1 8 8
- 6 5
-120
- 8 8
- 1 7 8
- 1 2 3
- 3 2 6
- 2 4 1
-234
- 2 7 8
1402
451
1163
-204
- 2 3 5 1
-252
-506
-570
^ \ / b c a l . / m o l e - " K .
13
16.7
18.0
18.3
18.3
18.6
18.3
25.4
18.5
18.7
22.9
21.0
20 .8
20.4
20 .1
20.7
19.9
20.2
23.0
21.9
22.2
22.6
22 .3
28 .8
21.2
24 .8
20.4
20 .7
25 .3
P e r r y , C h e m i c a l E n g i n e e r s Handbook, F o u r t h E d . p . 3 -107 , Ref. (91).
0.4
E 0.3 o 0.2 ^ 0.1
1 1
-
1 1
1 1 1
3^ ^ ^ ^ ^ ^ N 2 _ ^ ^
""^^ C 0 _ _ _ ^ 1 1 1
1
- ^ 2
1
1 1
y^ tC02,SF6
1 1
1
%
1
0 GLL-633-ij-itOB
20 80 40 60
% 1/T F i g . 2. D e v i a t i o n c u r v e s for H2. ^Z' ^ 2 ' ^ ^ ' ^ ' - ' 2 ' ^'^'^ S F ^ .
00
100
as 0.7
0.6
05
04
03
02
0.
0
I I I !
—
1 1 1 1
1 1 1 1
X
JY / ^
J^ J^
^ ^
^ ^
1 1 1
1
>xClS '̂'"'*
^ 2 ' * ' \ \ \ —
% -
¥ 1 1 \
1 0
GLL-633-436A
20 40 60 % 1/T
^
80 100
F i g . 3. Dev i a t i on c u r v e s for Xe , K r , CH4, O^. and A r .
-10
-
O
O
O
00
o
U ro
o
CO
O
O
<M
O
h-
\ MM
*
o
t--cf ro
oo
1
^
O (M
^
pq
(NJ
1—
1
u
r—1
U cq
u
m
> 3 u
0
•iH
•H
> 0) p
Th
hi
(ujp
) p
HF
, N
^O.
d (a
tm)
O
O
O
.—
.—
IV)
rv)
4^
O
-f̂
bo
no
CT)
o
-P̂
.O
o p
o —
—
no
'4̂
CD
bo
O
no
N0
,HC
Nd
(atm
) _
1 2
\ ^
o
o
2 \
^ CD
\
\
\. 1
1 $\
\ \V
\ \
^ \
2 1
—
X "n
—
\\
-\
\\ ro
1 o
oo
oo
op
p —
—
no
O
J -P̂
en
(J
) N
e,C
Cl4
,Sn
CL
d (a
tm)
-IT
-
-12 -
who fitted the data for the vapor p r e s s u r e of H2O with an equation utilizing
exponential functions. Manifestly, then, the experimental determinat ion of
vapor p r e s s u r e always will be capable of g r ea t e r prec is ion than can be ob
tained with simple equations containing up to four constants , and it is only
with considerable effort that special equations have been developed that have
sufficient flexibility to reliably smooth such h igh-precis ion data.
It appeared, there fore , that a deviation curve based on a relat ion as
s imple as Eq. 6 would:
1) Be capable of as g rea t a degree of prec is ion as m o r e complicated
equations.
2) Conform m o r e closely to the behavior of rea l v a p o r - p r e s s u r e curves
so as to more c lear ly define the magnitude of exper imental e r r o r s .
3) Establ ish prec ise ly the value of d P / d T at any t e m p e r a t u r e .
4) Es tabl i sh prec ise ly the value of the vapor p r e s s u r e above one a tmo-
shpere re la t ive to the boiling point as stated here in , and to the t empera tu re
scale used by the original investigator as t ransposed to an ice point of 273.15''C
5) Fix m o r e prec ise ly the correspondence between the cr i t ica l p r e s s u r e
and the cr i t ica l t empera tu re (as recognized by Picker ing (93)).
The above points will be further amplified in the discuss ion below.
B. EXPERIMENTAL DATA
In considering the need for a comprehensive investigation of the data r e
ported in the l i t e r a tu re , the following points were weighed. The most accura te
published corre la t ions of v a p o r - p r e s s u r e data above 1 a tm. , with the exception
of NBS Circular 564 (84), dated back to the Landol t -Bornste in "Physikal i sch-
Chemish Tabellen" (65), las t revised in 1936, and the International Cr i t ica l
Tables (54), published in 1928. Stull 's m o r e recent (1947) resu l t s (108) based
on Cox-Chart cor re la t ions had been shown by Mil ler (78) to be ser iously in
- 1 3 -
e r r o r because the cor re la t ion used was such that the v a p o r - p r e s s u r e curve
was made to approach the cr i t ica l point in the opposite direct ion from the rea l
v a p o r - p r e s s u r e curve shown in F igure 1. In addition, a considerable amount
of new v a p o r - p r e s s u r e data had been published.
A considerat ion of the data available indicated that initially our invest i
gation would be well served if r e s t r i c t ed to 30 or so inorganic subs tances .
For half of these data of high prec is ion had been repor ted; the remainder were
of sufficient industr ia l and scientific impor tance to justify a careful r e - e x a m i
nation of the data repor ted p r io r to 1947.
In addition to the works mentioned above, we would like to acknowledge
our indebtedness to the bibliographic works of Kelley (59) and of Picker ing (93);
these have been of invaluable help in searching the l i t e r a tu r e . The original
sources of all work relevant to the compounds considered by us have been
studied, but we have cited only those containing data on which our resul ts a r e
based or those represent ing e r r o r s or omiss ions in the previous l i t e ra tu re
s o u r c e s . Where the resu l t s of only the most recent invest igators have been
used, a thorough analysis of the work of the previous invest igators has been
given by one or m o r e of the authors ci ted.
Since the details of the experimental work pert inent to the data used he re
a r e d iscussed by the original au thors , only general comments need be given
he re regarding exper imental methods . It is well recognized that the prec is ion
of v a p o r - p r e s s u r e data will be governed by the following considerat ions: (1)
purity of sample; (2) prec is ion of p r e s s u r e measurement ; (3) prec is ion of
t empera tu re m e a s u r e m e n t s ; and (4) adequate prec is ion of t empera tu re control
and the design of the apparatus such as to insure the at tainment of t rue liquid-
vapor equi l ibr ium.
-14-
Until the relat ively recent advent of such powerful analytical tools as
m a s s spectrography and gas chromatography, the methods available for d e
terminat ion of the purity of sample were r e s t r i c t ed largely to s imple m e a
surements such as density, boiling point, and refract ive index. In the ear ly
days , invest igators making v a p o r - p r e s s u r e measu remen t s often pioneered in
the synthesis of the ma te r i a l itself; in notable c i r cums tances , as mentioned
below, these v a p o r - p r e s s u r e determinat ions have not been repeated even though
the purity of the original ma te r i a l is manifestly suspect in the light of more
recent synthetic work. Possibly the mos t r emarkab le case is that of a r s i n e ,
for which no h igh -p re s su re m e a s u r e m e n t s have been made since Fa raday ' s
work up to 13 a tm. , repor ted in 1845.
Since the development of the Keyes deadweight piston gage, for which the
vapor p r e s s u r e of CO^ at 0°C. has been established as the standard ca l ib ra
tion point, this ins t rument has been used ei ther as the working gage or as the
p r i m a r y standard for all prec is ion measu remen t s above 2 or 3 a tm. This gage
is sensi t ive to 0.001 a tm. at p r e s s u r e s up to 150 a tm.
The t empera tu re sensitivity corresponding to this degree of p r e s s u r e
sensitivity is 0.0007 °C. in the neighborhood of the cr i t ica l point, where d P / d T
is about 1.5 a t m . / ° C . This degree of sensitivity is attainable ei ther with mul t i -
junction thermocouples , which a r e to be general ly p re fe r red below lOO^K., or
with platinum res i s t ance t he rmomete r s above this t e m p e r a t u r e .
An important problem stil l unresolved is the fixing of the boiling points
of many well known liquids on the International Tempera tu re Scale. Until this
has been done, the reported v a p o r - p r e s s u r e values mus t be considered, at
bes t , to be only internally consistent with the boiling point as determined by
the invest igator . Indeed, much of the confusion existing in the l i t e ra tu re today
has been caused by the h is tor ica l fluctuation of the accepted value of the ice
- 1 5 -
point on the Kelvin scale and the impossibil i ty of using a simple additive r e l a
tionship to equate the many h is tor ic Kelvin scales which have been used.
Undoubtedly the g rea tes t source of e r r o r — both in frequency and degree
to be found in v a p o r - p r e s s u r e data has a r i s e n from poor t empera tu re control .
Poor thermosta t ing is general ly the cause of e r r o r when the repor ted t empera
ture does not correspond to the p r e s s u r e measu remen t ; this is par t icu lar ly a
cause of e r r o r near the c r i t i ca l point because of relat ively sluggish at tainment
of l iquid-vapor equil ibr ium. Where the heat of vaporizat ion is relat ively large
at t empera tu re s below the c r i t i ca l point, this heat exer ts a se l f -cor rec t ing ef
fect on measu remen t s which tends to check t empera tu re f luctuations. However,
near the cr i t ica l point, AH becomes smal le r ; in addition, the difference be
tween the liquid and vapor density dec r ea se s markedly , thus increasing the
difficulty in maintaining equil ibr ium.
Our examination of the deviation curves derived from the data convinced
us that the in te res t s of accuracy would be bes t served by:
1) Computing the deviations relat ive to the mos t accura te boiling point
available in the l i t e r a tu re .
2) Using the most accura te data to define a general behavior pat tern for
the deviation curve , including specifically a pat tern for the location
of the maximum and minimum and the re la t ive slopes of the var ious
portions of the deviation curve .
3) Est imat ing the accuracy of the data by thei r agreement with a smooth
curve conforming to this generally established pa t te rn .
Since there is a high conformity of the data to these r equ i r emen t s , we feel that
the precis ion of the method has been positively demonst ra ted and the existence
of situations where g r e a t e r - t h a n - n o r m a l e r r o r s had occur red could be d is t in
guished. We feel these c r i t e r i a a r e manifestly m o r e re l iable indica tors of the
-16-
prec is ion of the data than those claimed for the exper imenta l apparatus by the
original au thors . The general accuracy of the best values given in this repor t
re lat ive to the International Tempera tu re Scale is probably not bet ter than
±0.0 1°C. , with a corresponding p r e s s u r e var ia t ion at the t empera tu re in
question. The absolute accuracy of the values is generally to one less dec i
mal point than stated, but these values can be used for purposes of internal
compar ison (of d P / d T , for example) to the number of places quoted.
C. SCOPE OF THIS WORK
The usefulness of deviation curves to r ep resen t v a p o r - p r e s s u r e data
accurate ly from one a tmosphere to the c r i t i ca l point is well recognized.
There has been, however, no sys temat ic effort to compare data for different
substances with the same base function, each author adopting a mathemat ica l
function giving a p re fe r red fit to his data . In many ca se s , deviations from the
equations have not been plotted, and the problem of distinguishing between
potentially rea l effects, sys temat ic deviations from an assumed and perhaps
inadequate empir ica l equation, and random deviations due to exper imental
e r r o r has general ly been left to the r e a d e r . In cases where the precis ion of
the data is within 0.001 a tm. , and a corresponding t empera tu re prec is ion , this
problem is obviated. However, where exper imental e r r o r s and rea l effects
a r e given equal weight in r e g r e s s i o n - c u r v e t rea tment , the resu l t is inevitably
confused. Histor ical ly , then, the v a p o r - p r e s s u r e deviation curve has been
t rea ted as a mathemat ica l tool whose cha rac te r i s t i c s were imposed by the
special conditions of each individual problem.
The objective of this work was to de te rmine whether , if deviation curves
for a la rge number of inorganic liquids were plotted on a single bas i s , any
common cha rac t e r i s t i c s could be established for substances whose vapor p r e s
su res were accura te ly known, and whether curves having these common
-17 -
cha rac t e r i s t i c s would give a reasonable fit for other substances whose r e
ported vapor -pressure data were of questionable re l iabi l i ty .
In this work all data have been compared to the Kirchhoff equation
l°g ^K = - t ° C + l 7 3 . 1 5 + S , (^)
and the deviation has been expressed as
d - P . . - P , . (8)
K obs
Tempera tu res expressed in the Kelvin scale were converted to degrees Cel
sius on the basis of the ice point used by the invest igator , although we r ea l
ized that these h is tor ic Kelvin scales were not s t r ic t ly equivalent to the p r e s
ent 1954 Kelvin scale based on an ice point of 2 73.15°K. The A and B con
stants were evaluated using selected boiling points and cr i t ica l points, and
were expressed to six f igures . The considerat ions governing the select ion of
these values will be d iscussed in m o r e detail below. Equations 1 and 2 were
combined and the deviations were computed on a IBM 650 machine . The de
viations obtained were plotted to a scale consistent with the prec is ion of the
data, the mos t p rec i se plots being readable to 0.001 atm, and a corresponding
t empera tu re prec i s ion . II. VAPOR PRESSURE DEVIATION CURVES
A. CONSTRUCTION OF DEVIATION CURVES
In order to fully define the deviation curve using eqs . 1 and 2, the fol
lowing information was required:
1. The boiling point, T, ;
2. The cr i t ica l t e m p e r a t u r e , T ;
3. The cr i t ica l p r e s s u r e j P ; c
4. Vapor-pressure data between T, and T .
- 1 8 -
Satisfactory boiling point values based on accura te , low p r e s s u r e work
were found in the l i t e ra tu re for mos t of the subs tances . In a few c a s e s , the
boiling point used was determined by us from the h igh -p re s su re deviation
curve presented in this repor t .
By passing the l inear Kirchhoff equation through the boiling point and
cr i t ica l point, the value of d is necessa r i ly 0 at one a tmosphere and at the
cr i t ica l p r e s s u r e . In some cases minor cor rec t ions in P have been made ^ c
by adjusting d ra ther than by recalculat ing the constants in eq. 1. (See
tables in P a r t III.)
In cases where the cr i t ica l point was established by accura te PVT de
terminat ions of the coexistence envelope, in conjunction with adequate vapor
p r e s s u r e measu remen t s between T, and T , no problem was found in con
structing a deviation curve .
In other cases a lack of correspondence between P and the vapor p r e s
sure predicted by the deviation curve at T was revealed by a g ross discon
tinuity in the deviation curve at the cr i t ica l point. Here the p r ime c r i t e r ion
which we used was the necess i ty for a genera l correspondence of the max i
mum and minimum of the deviation curve with those for s imi la r subs tances .
Then, since only two data a r e neces sa ry among i tems 2, 3, and 4, the choice
of ei ther T or P fixed the other . The considerat ions involved in the choices c c
of T and P will be d iscussed below in connection with the specific com-c c ^
pounds involved.
B. SHAPE OF CURVES
For the general ized compar ison of the deviation curves , the t empera
ture range between the boiling point and the cr i t ica l point was normal ized on
a 1/T bas is and expressed as percent , where
%(1/T) = 100 r i / T ^ - l / T y p / T ^ - 1/T^j . (9)
-19 -
The curves a r e presented for each liquid individually in P a r t III of this r e
port but for the purposes of the general ized discuss ion, a r e var iously grouped
in Figures 1-5. It should be noted that in each of F igures 1-5, some curves
shown a r e determined from experimental data of a high degree of prec is ion .
Specifically, the well defined curves a r e those for H^, HD, D^, N , , CO, Ne,
Ar , O^^ CH^, Kr, Xe, N^O, CO^, NH^, SO^, SO3, HF, N^O^, and CCl^.
Curves for which empir ica l considerat ions were involved, to varying deg ree s ,
in fixing their positions were S i F . , CK. C2N2. ^^^2' SnCl . , NO, HCl, HBr,
SF^, H^S, HI, and HCN.
Referr ing to F igures 2-6, it can be seen that the curves fall into two
general c l a s s e s , as further i l lus t ra ted in F igure 7, where various points have
been designated by the l e t t e r s b , j , h, k, and c. The dist inction between
Class I and Class II is not fundamental but resu l t s from the a r b i t r a r y choice
of the normal boiling point as the lower te rminus of the curve . If a lower
t empera tu re were to be taken so as to i nc rease the bj d is tance in curve I, the
Class II curve would be obtained.
C. SLOPE OF CURVE AT NORMAL BOILING POINT
Comparison of eq. 6 with the exact Claus ius-Clapeyron equation
Rd (In P) ^ AH d ( l / T ) ' AZ
shows that
(10)
(4.5758)(AZ)(A) - AH^ ,̂ (11)
where AH, is the heat of vaporization at the boiling point corresponding to a
constant d (log P ) / d ( l / T ) slope, A, between T, and T ; and AZ is the differ
ence between the liquid and vapor compress ib i l i ty . According to Miller (78)
an average AZ for inorganic liquids at the boiling point is 0.97. Substituting
this value for AZ in eq. 5, AH, 's have been calculated and a r e given in Table I,
along with AH, values from NBS Ci rcu la r 500 (83) and P e r r y (91).
E o
LL5
CO
0.6
0 5
04
03
02
01
0
-0.1
-02
1 1
^ - . ^
- ^ ^ \ ^ ^ ^
^^^^^^
^ ^ ^ ^ ^ ^ ^
—
1 1 1
S i F 4 ^ , ^ /
7 ^"°'===::—"^^^ y
/ - ^
/
/ /
/
/
/ ^ ^ S O a
1
—
X -
/ \ y y \
0 GLL-633-439A
20 40 60 % I / T
80
2.4
2.0
1.6
1.2
0.8
0.4
0
-O.A
-o.e
E H—
o • o
rO
o (/)
[
]
100
F i g . 6. D e v i a t i o n c u r v e s for S i F , and SO.,.
2 1 -
% 1/T
Class I curve
% l / T
Class II curve GLL-637-1700
Fig . 7. Classes of deviation cu rves .
- 2 2 -
It can be seen from the above that the difference, AH, - AH, , should k b
indicate whether the slope of the deviation curve at the boiling point will be
positive or negative. Comparison of Column 4 in Table I with the deviation
curves given in P a r t III indicates that this c r i te r ion is quantitatively obeyed
in that, in 27 out of 30 c a s e s , the sign of the slope is cor rec t ly predicted.
The quantitative d ispar i ty of some of the AH differences as compared with the
slopes of the deviation curves leads us to observe , however, that because of
curva ture of the vapor p r e s s u r e t empera tu re function at the boiling point, this
difference may only be quantitatively obeyed for a few degrees above the boil
ing point. In addition, it is probably t rue that in some cases our average value
for AZ is not accura te and that in some cases the value used for AH, may be
inaccura te .
Table I also gives values of 4.5758 B, a psuedo-entropy t e r m , i . e . ,
AS, ,, cal . per degree per mole of vapor . As can be seen from the Table,
values of AS, /, above 21.0 a r e general ly found with associa ted l iquids.
D. RELATION TO LIQUID AND VAPOR DENSITIES ALONG
COEXISTENCE ENVELOPE
The upturn of the deviation curve at b in Class I and at j in Class II curves
is probably mos t closely related to la rge percentage changes which a r e be
ginning to occur in the liquid density along the bubble-point l ine. No c o r r e
lation of this point with coexistence data has been made , but it should be
pointed out as a ma t t e r of exper imental p rocedure that adequate and re l iable
v a p o r - p r e s s u r e data in this region a r e a p r ime requis i te for accura te ly de
fining the deviation curve . As the heat of vaporizat ion and the difference be
tween liquid and vapor volumes become rapidly sma l l e r , the problems of main
taining t empera tu re and p r e s s u r e equil ibrium a r e aggravated. However, the
problems a r e considerably less at this point than at t empera tu re s above point
- 2 3 -
k, and any effort expended in getting accura te measu remen t s in this region
pay dividends toward minimizing the effect of uncer ta int ies encountered in
the kc region. The inflection point at h appears to be due to the inflection
point in the vapor density along the dew-point line as mentioned previously.
It is of in te res t to comment on the evidence for f ine - s t ruc tu re effects
demonstra ted in the p rec i se ly determined c u r v e s . In examining the bjh r e
gion of the curves for accura te ly known subs tances , it is found in all 15 cases
that in this region the curve may be composed of two, th ree , or four near ly
s t ra ight sections joined by relat ively sharp cu rves . These s t ra ight sections
were par t icu lar ly evident for the Class I curves having no negative deviations;
i. e. , H^. N^j CO, Ar , O^i CH. , Kr, Xe, and HF and a r e str ikingly i l lus
t ra ted in the cases of N-, and CH. , for which l a r g e - s c a l e plots a r e provided
below. Although in most cases the data shown could be a lmost as well fitted
with smoother cu rves , and although four points cannot be said to conclusively
establ ish a s t ra ight l ine, it would be equally presumptuous to conclude, a
p r i o r i , that deviation curves must demons t ra te a low-order cu rva tu re , data
points notwithstanding.
E. CORRESPONDENCE OF MAXIMA AND MINIMA
Empir ica l ly , it appears that on the sca les plotted in F igures 2-6 the
peak k of the jhkc loop is located so that the angle formed by the s t ra ight s e c
tion of hk with the ver t ica l is for Class I curves from 60 to 80" and for Class
II curves from 20 to 40°; the angle general ly formed by kc is about half as
great ; and fu r thermore that the d ordinate values for j and k for s imi la r sub
stances do exhibit a general degree of cor respondence as shown in F igures
1-5, Thus the d = 0 requ i rement at P fixes P within relat ively nar row l imi t s .
Because the high d P / d T slope of the deviation curve at the cr i t ica l point is
superimposed on the contribution of the Kirchhoff equation, d P / d T may vary
- 2 4 -
between 1.0 and 2.0 atm-Z^C. For a d P / d T of 1.5 a t m . / d e g . , for example,
a p r e s s u r e difference of 0.01 a tm . is equivalent to a 0.0067''C. t empera tu re
difference. Thus it can be seen that the p r e s s u r e is an especially sensit ive
function of t empera tu re at the c r i t i ca l point. This m e a n s , of course , that
random tempera tu re e r r o r s near the cr i t ica l region r ep re sen t the highest de
gree of p r e s s u r e d ispers ion on the deviation plot. Complementing this , how
ever , is the magnification of the prec is ion with which the p r e s s u r e is fixed
by a well defined deviation curve . If the necess i ty is assumed for the k height
to correspond to a uniform pat tern for s imi la r substances to at leas t within
±0.05 a tm. as d iscussed above, P is fixed cer tainly within these l imits and c
correspondingly T is fixed to within about ±0.03 ' 'C.
F . CORRESPONDENCE OF DATA WITH DEVIATION CURVE
The following section p resen t s general considerat ions involved in s e
lecting the p re fe r red deviat ion-curve location for situations where the vapor
p r e s s u r e data were ambiguous.
In Figure 2, the accura te ly known curves were those of H^, D^, N^,
CO, and COp.
In the case of SF , the only consistent data were those of one investigator
in the kc region. The data in the bjh region were badly sca t te red and one in
ves t iga to r ' s data in the kc region demonst ra ted a l o w - p r e s s u r e "nose" between
k and c. Other examples of this "nose" effect have been found in the course
of this study, and, without exception, they have been found to be spurious
when compared with p rec i se m e a s u r e m e n t s . We have discounted these points ,
the re fore . The curve derived from the average of the sca t te red points in the
bjh region also was suspect in that this curve was not in harmony with the p r e
fe r red hkc data. F u r t h e r m o r e , this curve differed markedly from that of
COp, a compound with a s imi la r coexistence l ine . In this region the re fore .
-25 -
our p re fe r red curve was derived from the normal ized CO^ curve as descr ibed
below. To support this judgment it can be pointed out that N^ and CO, whose
molecular s imi lar i ty a r e well recognized (47), show pract ical ly identical de
viation curves in F igure 2.
In F igure 3 all curves a r e well defined by the data . In F igure 4, the
accura te ly known curves a r e NH^, N^O, and SO^. Three general problems
were encountered in locating the other curves in regions of poorly determined
data . In the case of Br^ and C^N^, where relat ively good data were available
in the bjh region, the problem was to choose a c r i t ica l p r e s s u r e cor respond
ing to the accepted T so that the bjh portion of the curves would form a mu
tually symmet r i ca l pat tern . This was done by adjusting the j and k peaks to
be in mutual correspondence with the other curves shown. In the cases of
HCl and H^S, no data were available in the bjh region, and in the case of CK,
the bj data departed markedly from the genera l s lope. The course adopted
here was to draw the curves to harmonize both with the hjk points and the
other bjh curves shown in F igure 4. In the case of Br_ no data were available
in the kc region, so this curve was drawn to be in mutual harmony with C L .
The third problem in Figure 4 with C L , HBr, and HI was that these data
exhibited excessive sca t te r overa l l . The p re fe r red curves were therefore
drawn so as to bes t approach the points giving curves matching the pa t te rn
established by HCl and H^S. Points deviating from this pat tern by more than
the normal confidence l imits were neglected. It can be seen by examining the
individual curves given below for these substances that a reasonable degree of
agreement with the data has been obtained in the jhk region where the re is l e ss
difficulty in attaining equil ibrium conditions.
In the case of NH^, a choice was made in the kc region between the data
of Beattie (8) and of Keyes (60). The data of Beattie were used because a
-26-
deviation curve following Keyes ' points indicated a c r i t i ca l p r e s s u r e 0.5 a tm.
lower than Bea t t i e ' s . Basing the deviation curve on A and B constants calcu
lated from Keyes ' indicated P would have not only lowered the k point below
that for CpNp but would also have lowered the j point to -0.55 a tm. , or 0.15
a tm. below any other compound shown in F igure 4. It was believed that Keyes
data were in e r r o r here and cr i t ica l values were chosen to correspond with
Beat t ie ' s points so that the deviation curve harmonized as shown in F igure 3.
A s imi la r situation is a lso d iscussed below in Section III. C.7 on CH>.
In F igure 5 the curves were plotted on different p r e s s u r e scales for
convenience in comparing shapes . Fo r Ne, C C l . , and SnCl . , the d ordinate
is 0.1 a tm. /d iv i s ion , for NO and HCN 0.2 a tm. /d iv i s ion , and for HF and N^O.
0.4 a tm, /d iv i s ion . The curves for HF, NpO ., Ne, CCl ., and SnCl. were well
determined by the data . The curve for HCN was found to fit the few observed
data well when matched with that for NpO .. The curve shown for NO was
drawn so as to best fit the few points that seemed to indicate a reasonable
curve and so as to harmonize with the other curves as shown.
F igure 6 p resen t s the deviation curves for SiF . and SO^. These curves
do not conform to those in the previous figures since the d's a r e not zero at
the boiling point and in the case of SO-,, a lso at the cr i t ica l point. By means
of this change, the deviation curves were able to be presented on a scale com
parable to those of F igures 1-4 without excessively large negative values for
the j min imum. It should be noted that the data for SO., in the kc region were
ambiguous but that the kc height shown was drawn to conform to that of SO^,
which appeared to be reasonable .
In the kc region we have noted that the prevail ing d i sagreements with
the mos t accura te data appear to be in the direct ion of lower p r e s s u r e s . This
has been found to be t rue in the cases of Ne, Ar, CH. , HCl, H^S, S F / , NH,,
- 2 7 -
N-O ., and SnCL. In the cases of HBr and HI, where deviation curves were
located so as to correspond to curves for other substances determined by a c
cura te data , data which matched the curve in question in the jhk region were
low in the kc region. We a r e unable to advance any firm reasons for expect
ing exper imental e r r o r s to prevai l in this direction; however, the re la t ive
absence of sca t te r in the other direct ion tends to suggest that this is a sys tem
atic e r r o r . Hence, in the absence of consistently re l iable data in this region,
we have located the curve so as to be symmet r i ca l with s imi la r substances
having approximately the same k coordinates and have avoided points to the
right of k which would flatten the peak and requ i re a d ras t i c inc rease in kc
curva ture and s lope. Substances for which re l iable data were completely un
available in the jhkc region have not been considered in this study. It should
be emphasized that the utility sought for a hypothesis of the genera l behavior
of the deviation curve is that in the face of contradictory data, it m o r e closely
approximates the probable position of the deviation curve than does r e g r e s s i o n
line t rea tment ,
III. DEVIATION CURVES AND TABLES OF INTERPOLATED
VAPOR PRESSURES
A, PROCEDURE
Deviation curves were prepared as descr ibed above and a r e given in this
P a r t in connection with each specific subs tance . The text accompanying each
curve below cites the sources of the data used and d i scusses the considerat ions
involved in locating the p re fe r red position of the curve . Rather than at tempt
to reproduce the l a r g e - s c a l e deviation plots , deviation values read from these
plots have been included in the Tables of Interpolated Vapor P r e s s u r e s . The
f i rs t column of the Tables of Interpolated Vapor P r e s s u r e gives the t e m p e r a
ture in " C , the second column gives the interpolated vapor p r e s s u r e calculated
by the equation
-28 -
P. = Pj^ - d, (12)
and the third and fourth columns give P „ and d, respect ively . The rel iabi l i ty
of the las t figure given for P . is general ly quest ionable. In the cases of hy
drogen, nitrogen, oxygen, methane , and carbon dioxide, reduced size figures
of the original l a r g e - s c a l e plots of d against "C. a re also presented . This
has been done to show for these substances the bas is for our judgment as to
mos t probable position of the deviation curve where the resu l t s of severa l in
ves t iga tors a r e in d i sagreement , and to exemplify the nature of " f ine - s t ruc
t u r e " effects which have been general ly brought out by high-precis ion m e a
s u r e m e n t s . The other subs tances , for which only sma l l - s ca l e graphs a r e
presented , fall into one of two categor ies : ei ther the prec is ion of the data of
severa l invest igators is adequately represen ted by the small scale used, or
the data of a single invest igator is considered to be of super ior rel iabil i ty and
ea r l i e r resu l t s have been rejected on the bases mentioned above. Compar i
sons with these other data have usually been presented by the authors cited.
B. SUMMARIZED CRITICAL PROPERTY AND VAPOR
PRESSURE VALUES
In addition to the individual tables of vapor p r e s s u r e s . Table II is p r e
sented showing the comparison of our p re fe r red cr i t ica l values with those s e
lected by Stull (108) and Kobe and Lynn (63). In genera l , these two authori t ies
values correspond with Picker ing (93) and with other authori t ies in the In ter
national Cri t ical Tables (54).
Our interpolated vapor p r e s s u r e tables giving the vapor p r e s s u r e s for
even t empera tu re values may be compared direct ly with the International Cr i t
ical Tables . For compar ison with Stull 's va lues , we have prepared Table III
giving t empera tu re values for even p r e s s u r e va lues .
-29 -
T A B L E II
SUMMARY O F S E L E C T E D DATA C O M P A R E D WITH L I T E R A T U R E
Subs tance
e q - H ^
" " " 2 HD
e q - D ^
n D^
Ne
^ 2 CO
A r
°2 CH4
NO
Kr
Xe
S iF^
N^O
C O ,
HCl
HBr
H , S
HI
Cl^
NH,
S O ,
H F
HCN
N2O4 B r ,
SO 3
CCI4
SnCl ,
b p °C
- 2 5 2 88
- 2 5 2 77
- 2 5 1 02
- 2 4 9 . 5 2
- 2 4 9 49
- 2 4 6 06
- 1 9 5 78
- 191 48
- 1 8 5 91
- 1 8 2 97
- 1 6 1 49
- 1 5 1 74
- 1 5 3 40
- 108 12
- 9 0 2^̂
- 8 8 46
- 5 6 57̂ =
85 03
66 72
-51^^
- 6 0 19
- 3 5 35
- 3 4 05
- 3 3 35
- 2 1 15
- 1 0 02
19 5
25 70
21 0
58 2
44 55
76 7
114 1
c •C
Stull (108) P c
a t m
C r i t i c a l P r o p e r t i e s
Kobe and Lynn (63) This Work
•240 0 12 80
•228 3
147 2
138 7
122 0
118 9
-82 1
-92 9
-63
-14 2
36 5
31 1
51 4
90 0
100 3
151
144
132 4
126 6
157 2
183 5
158
302 2
218 3
283 1
318 7
26 90
33 5
34 6
48 0
49 7
45 8
64 6
54
36 7
71 7
73 0
81 6
84 4
88 9
82
76 1
H I 5
58 2
77 7
50 0
99
121
83 6
45 0
37 9
T c
•c -240 22
-239 9
-237 25
-234 90
-234 81
-228 7
-147 0
•140
•122
•118 4
-82 1
-93
-63 8
16 59
-14 1
36 5
31 0
51 4
90 0
45 55
100 4
150
144
132 3
127
157 5
183 5
158
311
218 2
283 2
318 7
P c atm
12 77
12 80
14 645
16 282
16 432
26 9
33 5
34 5
48 0
50 1
45 8
64
54 3
58 0
36 7
71 7
72 9
81 5
84 0
37 11
88 9
81
76 1
111 3
59
77 8
53 2
100
102
83 8
45 0
36 95
-240 IT^
- 2 3 9 92^
- 2 3 7 25^
- 2 34 90^
- 2 3 4 82^
- 2 2 8 75^
- 1 4 6 93^
-140 23^
- 1 2 2 29^
-118 38^
-82 6 1 ^
- 9 2 9^
- 6 3 77^
16 59^
- 1 4 17*
36 4 3 *
31 04*
51 54*
90 0 *
45 64*
99 9 *
150 7*
144 1^
132 50*
128 3 0 *
157 50*
188*
183 5*
158 2*
3 1 1 *
217 7*
283 15*
318 7*
c a t m
12 76^
12 80a
14 645*
16 28*
16 42*
26 19*
33 54*
34 53*
48 34*
50 14*
45 49^
64 6*
54 31^
57 64*
36 6 6 *
71 60*
72 8 4 *
82 0 7 ^
84 5*̂
37 19*
88 2 6 *
81 9^
76 1*
112 53^
59 98^
77 8 1 *
64 0 7 *
48 89*^
99 6 6 ^
102*
81 4 4 ' '
44 9 7 *
36 9 5 *
' L i t e r a t u r e va lue ci ted in tex t
' 'Value d e t e r m i n e d f rom dev ia t ion c u r v e in th is work
T r i p l e pt above 1 a t m
30
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rO
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in
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fu
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- 3 1 -
An additional, m o r e meaningful compar ison between our deviation curve
and the Stull and ICT values was made by us by comparing the deviations of
these values with our deviation curve . It appears that Cragoe ' s calculated
values in the International Cr i t ica l Tables ag ree fairly well with our values .
Stull 's va lues , however , invariably show la rge negative deviations and no pos i
tive deviat ions. This is to be expected from the nature of the Cox Chart cor
relat ion method used by him which always approaches the cr i t ica l point from
the negative ra ther than the positive deviation side.
While the choice of a location for the deviation curve in the absence of
rel iable data is difficult, especially in cases where apparently re l iable data
a r e in conflict, it is believed that the procedures which have been used have
resul ted in the c loses t possible approach to the t rue vapor p r e s s u r e . This is
based on the demonstra t ion by this study of a high degree of consistency in the
general shape of the deviation curve . F o r severa l different m a t e r i a l s the
curves a r e a lmost identical; for ins tance, the groups N^ and CO; HF and N^O.;
0 ^ , A r , Xe, Kr, and CH, show this t r a i t . The demonstra t ion of conformity of
the deviation curve behavior with the resu l t s of published studies on vapor p res
sure and heats of vaporizat ion also supports this p rocedure . On this bas is the
reasons for rejecting data which a r e in radica l d i sagreement with this behavior
appear justified.
It is worth noting that in addition to NO no rel iable high p r e s s u r e data
a r e available in the l i t e ra tu re for such common substances as C F , , CS-,, COS,
COCl^. SiH^, PH^, ASH3, H2Se, N^H^, BCI3, BF3 , SiCl^, and GeCl^.
It is hoped that this study has sufficiently demonst ra ted the utility of the
deviation curve method as to encourage its future use to demons t ra te the con
sis tency and rel iabil i ty of experimental data .
- 3 2 -
C. INDIVIDUAL SUBSTANCES
1. Hydrogen Isotopes
Deviation curves have been computed for the following hydrogen isotopes
eq-H^, n-Hp, HD, eq-Dp, and n - D , . The curves plotted on a %(1/T) basis
a r e shown in Figure 8. It appears that on this bas is the curves for the ortho
and para forms coincide with each other both for H^ and D , but that cont ra ry
to Fr iedman , White, and Johnston (33) the curves for the H, and D^ isotopes
a r e separa ted from each other by about 5 to 6 % in the b-k region, with HD
falling between Hy and D^. Plotting the curves on a r educed- t empera tu re
basis as was done by F r i edman , White, and Johnston does not appreciably r e
duce this separat ion, since the reduced boiling points do not differ by more
than 1%.
The boiling points quoted in Table II a r e due to the following authors :
n-H2 (118); eq-H^; HD, and eq-D^ (51); and n-D2 (43).
The sources of c r i t i ca l constants used for deriving the Kirchhoff equa
tions were: n-H2 (117); eq-H^ (100); HD and eq-D^ (52); and n-D^ (32).
The v a p o r - p r e s s u r e data from the var ious investigations of the NBS (51,
112, 42) and Grilly (43) show good precis ion and a r e in good agreement .
F r i edman , White, and Johnston 's data on n-D^ (32) a r e in agreement with
Hoge's data and with the deviation curves in F igure 8 above point k. In the
b-k region, F r i edman , White, and Johnston 's resu l t s ag ree after their t em
pe ra tu re s in this region a r e adjusted to agree with Gri l ly ' s boiling point. In
the case of n-H^ nei ther White, F r i edman , and Johnston (116) nor Cath and
Kammerl ingh Onnes (20) agree prec ise ly with Gril ly, as can be seen from
Figure 9. The deviation curve shown in F igure 9 was obtained by projecting
a curve based on Gri l ly ' s resu l t s and coinciding with the deviation curve for
eq-Hp shown in F igure 8.
- 33 -
(33) F r i e d m a n , A. S. , Whi t e , D. , and J o h n s t o n , H. L . , J . C h e m . P h y s .
19, 126 (1951).
(118) Wooley , H. W. , Scot t , R. B . , and B r i c k w e d d e , F . G. , J . R e s . Na t l .
B u r . Std. 4 1 , 379 (1948).
(51) Hoge , H. J . , and A r n o l d , R. D . , J . R e s . Na t l . B u r . Std. 47 , 63 (1951).
(43) G r i l l y , E . R. , J . A m . C h e m . Soc . 73 , 843 (1951).
(117) Whi t e , D. , F r i e d m a n , A . S. , and J o h n s t o n , H. L . , J . A m . C h e m .
Soc . 72, 3565 (1950).
(100) R o d e r , H. M. , D i l l e r , D . E . , W e b e r , L . A . , and Goodwin, R. D . ,
C r y o g e n i c s 3, 16 (1963).
(52) Hoge , H. J . , and L a s s i t e r , J . W. , J . R e s . N a t l . B u r . Std. 4 7 , 75 (1951).
(32) F r i e d m a n , A. S. , Whi te , D. , and J o h n s t o n , H. L . , J . A m . C h e m .
Soc . 73 , 1310 (1951).
(112) W e b e r , L . A . , D i l l e r , D . E . , R o d e r , H. M. , and Goodwin, R. D. ,
C r y o g e n i c s 2^ 236 (1962).
(42) Goodwin, R. D. , D i l l e r , D. E . , R o d e r , H. M. , and W e b e r , L . A . ,
J . R e s . Na t l . B u r . Std. 67A, 173 (1963).
(116) Whi te , D. , F r i e d m a n , A . S. , and J o h n s t o n , H. L . , J . A m . C h e m .
Soc . 72, 3927 (1950).
(20) Ca th , P . G. , and K a m m e r l i n g h O n n e s , H. , Konink l . Ned. Akad .
W e t e n s c h a p . P r o c . S e r . B 26, 490 (1917) L e i d e n C o m m . No. 152a.
U.H-'-h
0.40
0.36
0.32
0.28
^ 0.24 o
Z 0.20
0.16
0.12
0.08
0.04
-
—
—
—
—
—
—
—
i . ^
H2^y^
yyy y7x
1 ^ ^ ^ H D
1 1 1
^ D 2
- - — = 5 : , ^
\ v —
\ ~
\ ""
\ ~
\ ~
\ —
\ —
\ —
1 1 '
0
I
I
10 20 30 40 60 GLL-637-1702A
50
% (l/j)
F i g . 8. D e v i a t i o n c u r v e s for H i s o t o p e s .
70 80 90 100
040
E
• o 020
0
-004
6U-633-44M
n-H2
• Cath and Kammerlingh Onnes
• White
* Wooley
° Gri l ly
_L -253 -252 -240 -239
Fig . 9. Deviation curve for n-H2 vs t °C .
- 3 6 -
T A B L E IV
V A P O R P R E S S U R E O F e q - H ^
log P^ = - 5 8 . 1 5 9 1 / T + 2.86950
^' °*^- P i ' a t m . -p^, a t m . d, a t m
- 2 5 2 . 8 8 2 LOOO LOOO .000
252.50 1.116 1.130 .014
252.0 1.284 1.317 .033
251.5 1.472 1.525 .053
251.0 1.677 1.753 .076
250.5 1.901 2.003
250.0 2.144 2.276
249.5 2.410 2.572
249.0 2.698 2.892
248.5 3.012 3.237
248.0 3.350 3.606 .256
247.5 3.713 4.OOO
247.0 4 .102 4 .420
246.5 4 .518 - 4 .866
246.0 4 .961 5.338
245.5 5.435 5.836
245.0 5.943 6.360
244.5 6.486 6.911
244.0 7.OBO 7.487
243.5 7.670 8.091
243.0 8.303 8.720
242.5 8.998 9.375
242.0 9.722 10.056
241.5 10.489 10.763
241.0 11.299 11.495 .196
'240.5 12.164 12.252 .088
240.174 12.759 12.759
.102
.132
.162
.194
.225
.287
.318
.348
.377
.401
.417
.425
.427
.421
.417
.377 •
.334
.274
- 37 -
T A B L E V
V A P O R P R E S S U R E O F n - H ^
log P^ '-^ - 5 8 . 3 3 6 5 / T + 2.86244
t. °C. P . , a t m . P^, a t m
- 2 5 2 . 7 7 1.000 1.000
252.50 1.080 1.090
252.00 1.241 1.271
251.50 1.421 ^ 1.472
251.00 1.620 1.693
250.50 1.838 1.936
250.00 2.075 2.200
249.50 2.334 2 .488
249.00 2.616 2.798
248.50 2.920 3.132
248.00 3.244 3.491
247.50 3.597 3.874
247.00 3.974 4 .282
246.50 4 .375 4 .715
246.00 4 .803 5.173
245.50 5.260 5.657
245.00 5.749 b . i 6 7
244.50 6.273 6.703
244.00 6.830 7.264
243.50 7.423 7.851
243.00 8.048 8.464
242.50 8.705 9.102
242.00 9.403 9.765
241.50 10.146 10.454
241.00 10.927 11.167
240.50 11.765 11.905
240 00 12.641 12.667
2 3 9 . 9 i b 12.797 12.797
- 3 8 -
T A B L E VI
V A P O R P R E S S U R E O F HD
log P,^ = - 6 7 . 2 8 4 8 / T -f- 3.04002 is.
t, "C. p . , a t m . P , , , a t m . d, a t m , 1 K
-251.017 1.000 1.000 .000
250.5 1.159 1.173 .014
250.0 1.331 ^ 1.360 .029
249.5 1.522 1.567 .045
249.0 1.732 1.794 .062
248.5 1.960 2.044 .084
248.0 2.208 2.31r .108
247.5 2.477 2 . 6 1 i .134
247.0 2.769 2 .931 .162
246.5 3.085 3.275 .190
246.0 3.428 3.646 .218
245.5 3.796 4 .042 .246
245.0 4 .191 4 .465 .274
244.5 4 .613 4 .915 .302
244.0 5.064 5.394 .330
243.5 5.543 5.898 .355
243.0 6.054 6.432 .378
242.5 6.596 6.994 .398
242.0 7.172 7.586 .414
241.5 7.784 8.206 .422
241.0 8.431 8.855 .424
240.5 9.117 9.533 .41b
240.0 9.841 10.240 .399
239.5 10.609 10.977 .368
239.0 11.420 11.742 .322
238.5 12.280 12.536 .256
238.0 13.187 13.360 .173
^37.5 14.152 14.212 .060
237.252 14.645 14.645 .000
-39 -
TABLE VII
VAPOR PRESSURE OF eq-D^
- 7 4 . 8 8 0 1 / T 4- 3.16926
t. "C.
-249 .523
249.5
249.0
248.5
248.0
247.5
247.0
246.5
246.0
245.5
245.0
244.5
244.0
243.5
243.0
242.5
242.0
241.5
241.0
240.5
240.0
239.5
239.0
238.5
238.0
237.5
237.0
^36.5
25b.0
235.5
235.0
234.898
l o g P j ,
P , a t m
1.000
1.005
1.159
1.329
1.518
i .724
1.951
2.198
2.4b8
2.757
3.070
3.406
3.742
4 .159
4 .577
5.023
5.498
6.005
6.545
7.117
7.726
8.370
9.054
9.775
10.536
11.335
12.180
13.074
14.017
15.015
l b .059
16.282
P R
2
2
2
2
3
3.
3,
4
4,
5.
5.
6.
6,
7.
8.
8.
,, a t m
.000
.007
.171
.354
.556
.778
.022
.288
.578
.891
.230
.595
.958
.403
.849
.323
.826
.359
.921
,513
, 1 3 D
790
9.475
10.
10.
1 1 .
12.
13.
14.
15.
16.
191
939
718
528
570
244
150
087
16.282
- 4 0 -
T A B L E VIII
V A P O R P R E S S U R E O F n - D ^
log P^ = - 7 5 . 1 3 5 7 / T + 3 .17564
t, °C. P . , a t m . P..., a t m . d, a t m .
1 xS.
- 2 4 9 . 4 9 1.000 1.000 .000
249.0 1.149 1.160 .011
248.5 1.318 1.341 • . .023
248.0 1.506 1.542 ' .036
247.5 1.713 ' 1.763 .050
247.0 1.938 2.006 .068
246.5 2.185 2 .271 .086
246.0 2.450 2.560 .110 245.5 2.739 2.872 .133
245.0 3.051 3.210 .159
244.5 3.388 3.574 .186
244.0 3.750 3.964 .214
243.5 4 .138 4 .381 .243
243.0 4 .554 4 .826 .272
242.5 5.000 5.300 .300
242.0 5.475 5.802 .327 241.5 5:981 6.334 . : i o j
241.0 6.518 6.896 3 78
240.5 7.089 7.488 .399
240.0 7.695 8.112 .417
239.5 8.338 8.766 428
239.0 9.018 9.451 .433
238.5 9.740 10.168 .428
238.0 10.502 10.916 .414
237.5 11.308 11.696 .388
237.0 12.157 12.508 .351
236.5 13.054 13.352 .298
236.0 13.991 14.228 .237
235.5 . 14.986 15.136 .150
235.0 16.034 16.075 .041
234.82 16.421 16.421 .000
- 4 1 -
2. Neon
The boiling point and cr i t ica l -point data used in computing the deviation
curve for neon were taken from Grilly (44). The v a p o r - p r e s s u r e data used
in computing the deviation curve were kindly supplied to us in a pr ivate com
munication by Dr . Gri l ly. Gr i l ly ' s data agree with the deviation curve to
±0.001 a tm. in the low p r e s s u r e region and ±0.01 a tm. at p r e s s u r e s above
10 a tm. The deviation curve for neon is given in F igure 10.
(44) Gril ly, E. R. , Cryogenics 2, 226 (1962).
0.7
0.6
- 0 . 5
D O . 4
"^ 0.3
0.2
0.1
0
Ne
— • — - •
-246.06 -244
^
^ ^ ^ ^
^ ^ ^ ^ - " ^ ' ' ^ ^
-z^
^ ' s
-2^6
—
—
X -\ -
V J
-232228.75
T e m p ( ° C ) 1 1
0 GLL-637-1703
20 4 0 60 7o l / T
80 100
F i g . 10. Dev ia t i on c u r v e for N e .
-44-
3. Nitrogen
Since 1926 severa l invest igators (12, 27, 30, 74, 94) have measu red
the vapor p r e s s u r e of nitrogen above 1 a tm. , and the d i sagreement between
them shown by Figure 11 is not as ser ious as repor ted by Michels . More
over, F r i edman and White's c r i t ica l point values (31) a r e in good agreement
with his v a p o r - p r e s s u r e data and also with Michels ' r e s u l t s . Therefore , we
have selected a c r i t i ca l t empera tu re of -146.93°C. to fit the c r i t i ca l p r e s
sure of 33.54 a tm. as given by F r i edman and White (31), A boiling point of
-195.78*'C. has been selected as best fitting our deviation curve . This is
in good agreement with the resu l t s of Dodge and Giauque and Clayton (36).
Armst rong (5) has repor ted a value of -195.796°C.
In view of the demonst ra ted over -a l l high prec is ion of Michels ' m e a
su remen t s , and since his points most closely fit the expected course of the
deviation curve , we have used his data to locate our curve . In addition, his
r esu l t s appear to r ep re sen t a good mean value. The prec is ion of F r i e d m a n ' s
points appears to be equally good, with a sys temat ic difference of about
-0.04 a tm. between -180 and -158' 'C. F r i e d m a n ' s point at -147.63 "C. is
apparently in e r r o r , as a r e Dodge's data in the neighborhood of -151°C.
(12) Bloomer , O. T. , and Paren t , J . D. , Inst. Gas. Techn. Tes . Bull.
n , (1952).
(27) Dodge, B. F . , and Davis , H. N. , J . Am. Chem. Soc. 49, 610 (1927).
(30) F r i edman , A. S. , and White, D. , J . Am. Chem. Soc. 72, 3931 (1950).
(74) Michels , A . , Wassenaar , T. , DeGraaf, W. , and P r i n s . , C h r . , Physica
19, 26 (1953).
- 4 3 -
T A B L E IX
VAPOR PRESSURE O F Ne
log P ^ = - 9 8 . 5 6 1 4 / T + 3.63803
t . "C
- 2 4 6 . 0 5 8
2 4 6 . 0
2 4 5 . 5
2 4 5 . 0
2 4 4 . 5
2 4 4 . 0
2 4 3 . 5
2 4 3 . 0
2 4 2 . 5
2 4 2 . 0
2 4 1 . 5
2 4 1 . 0
2 4 0 . 5
2 4 0 . 0
2 3 9 . 5
2 3 9 . 0
2 3 8 . 5
2 3 8 . 0
2 3 7 . 5
2 3 7 . 0
2 3 6 . 5
2 3 6 . 0
2 3 5 . 5
2 3 5 . 0
2 3 4 . 5
2 3 4 . 0
2 3 3 . 5
2 3 3 . 0
2 3 2 . 5
2 3 2 . 0
2 3 1 . 5
2 3 1 . 0
2 5 0 . 5
2 3 0 . 0
2 2 9 . 5
2 2 9 . 0
2 2 8 . 7 5
P , , a t m .
1.000
1.017
1.178
1.359
1.559
1.780
2 . 0 2 3
2 . 2 9 0
2 . 5 8 3
2 . 9 0 3
3 . 2 5 1
3 . 6 2 6
4 . 0 2 8
4 . 4 6 3
4 . 9 2 9
5 . 4 3 2
5 . 9 7 1
6 . 5 5 0
7 . 1 6 8
7 . 8 2 7
8 . 5 2 7
9 . 2 7 2
1 0 . 0 6 2
1 0 . 8 9 9
1 1 . 7 8 6
1 2 . 7 2 5
1 3 . 7 1 6
1 4 . 7 6 0
1 5 . 8 5 7
1 7 . 0 0 9
1 8 . 2 2 2
1 9 . 5 0 1
2 0 . 8 5 3
2 2 . 2 8 4
2 3 . 7 9 6
2 5 . 3 7 5
2 6 . 1 9 3
P j ^ , a t m .
1.000
1.018
1.184
1.370
1.577
1.806
' 2 . 0 6 0
2 . 3 3 9
2 . 6 4 4
2 . 9 7 8
3 . 3 4 1
3 . 7 3 6
4 . 162
4 . 6 2 2
5 . 1 1 7
5 . 6 4 8
6 . 2 1 6
6 . 8 2 4
7 . 4 7 0
8-. 158
8 . 8 8 7
9 . 6 6 0
1 0 . 4 7 6
1 1 . 3 3 7
1 2 . 2 4 4
1 3 . 1 9 8
1 4 . 1 9 8
1 5 . 2 4 8
1 6 . 3 4 5
1 7 . 4 9 3
18 .690
1 9 . 9 3 8
2 1 . 2 3 7
2 2 . 5 8 8
2 3 . 9 9 0
2 5 . 4 4 5
2 6 . 1 9 3
d , atnn
. 0 0 0
. 0 0 1
. 0 0 6
. 0 1 1
.0 18
. 0 2 6
. 0 3 7
. 0 4 9
. O o l
. 0 7 5
. 0 9 0
. 1 1 0
. 134
. 1 5 9
. 1 8 8
. 2 1 o
. o 4 5
.274
. 5 0 1
: : 1
3 D C
5 8 8
.4 14
4 5 8
. 4 5 8
4 7 5
4 8 2
. 4 8 8
4 8 8
. 4 8 4
. 4 6 8
. 4 3 7
. 3 8 4
. 3 0 4
. 1 9 4
.0 70
. 0 0 0
-45 -
(94) P o r t e r , F . , and P e r r y , J . H. , J . Am. Chem. Soc. 48, 2059 (1926).
(31) F r i edman , A. S. , and White, D. , J . Am. Chem. Soc. 73, 5713 (1951).
(36) Giauque, W. F . , and Clayton, J . O. , J . Am. Chem. Soc. 55, 4875
(1933).
(5) Arms t rong , G. T. , J . Res . Natl. Bur . Std. 53, 263 (1954).
0.40
E 30.20 TO
0
GLL-633-441A
1
-
—
"
~
-
"C
1 1 1 1 1
N2
* Michels • Porter • Friedman • Dodge ' Giauque 0 Bloomer
« f *
Boiling point
1 1 1 1 1 1
1 1
«
• • — • •
1 1 1
1
•
^^^^
\
\
0
•
^—*
1 1
1 1 1
• •
• * . • • /
• / m D • /
j/^ •
1 i 1 1
1
*
/
•
1
1
• «
y /
1
1
*
^ • • •
1
I I I I •
•
V
\
\»
\ •
\
• \
\ Critical point^..\
1 1 1 1 1 1
—
-
-
-
-
-190 -180 -170 t(°c)
-160 150 144
r
I
F i g . 11 . D e v i a t i o n c u r v e for N2 vs t ^ C .
- 4 7 -
T A B L E X
VAPOR P R E S S U R E O F N^
log P = - 3 0 4 . 9 1 3 / T + 3.94097
t, "C. P . , a t m . PT^J a t m . d, a t m 1 K
195.78 1.000 1.000 .0
194 1.226 1.226 .0
192 1.526 1.526 ' ,0
190 1.879 1.879 .0
188 2 .291 , 2 .291 ' .0
186 2.769 2.769 . . .0
184 3.3 17 3.317 ,, .0
182 3.943 3.943 .0
180 4 .651 4 .652 T O . 0 0 1
178 5.435 5.450 .015
176 6.306 6.344 .038
174 7.276 7.340 , 0 D 4
172 8.352 8.443 .091
170 9.540 9.659 .119
168 10.844 10.994 150
166 12.269 12.454 185
164 13.822 14.043 221
162 15.510 15.766 . 2 5 D
160 ,17.342 17.628 v 286
158 19.326 19.634 .308
156 21 .471 ' 21 .788 .317
154 23.790 24.094 .304
152 26.295 26.555 „ .^oO
150 ' 28.999 29.176 .177
14~9 30.426 30.547 .121
148 ' 31.905 31.959 - 0 . 0 5 4
147 33.432 33.412 . • - 0 . 020
146.93 33.542 33.515 - 0 . 0 2 7
- 4 8 -
4. Carbon Monoxide
The deviation curve for carbon monoxide shown in Figure 12 is based
on the data of Michels et a l . (76). The curve agrees with the data to within
0.001 a tm. The boiling point is taken as -191.48' 'C. as de termined by
Giauque and Clayton (35). The deviation curve appears to be in excellent
agreement with the cr i t ica l data of Mathias and Crommel in (68).
(76) Michels , A, , Wassenaar , T. , and Zwietering, Th. N. Physica 18,
160 (1952).
(35) Giauque, W. F . , and Clayton, J . O. , J . Am. Chem. Soc. 54, 2610
(1932),
(68) Mathias , E. , and Crommel in , O. A , , Ann. Phys . 5, 137 (1936),
0.4
0.3
E 0.2
So.)
CO
• Michels • Giauque
1 1 -191.481 -185
1 1
1 -180
1
1 1 1 -175 -170 Temp (X )
1 1 1
1 -160
1
^"A-\ -
^
1 1 1 - I 50H40 .23
1
I
20 40 60 80 100
GLL-637-1705 % l/T
Fig . 12. Deviation curve for CO.
-RO
T A B L E XI
V A P O R P R E S S U R E O F CO
log P ^ fe - 3 2 5 . 8 J 3 / T + 3.98938
t . "C. P . , a t m . P , a t m . d, a t m . is.
191.48 1.000 1.000 .0
190 1.183 1.178 - 0 . 0 0 5
188 1.466 1.45b .010
186 1.798 ^ 1.782 .016
184 2.179 2 .161 .018
182 2.620 2.600 .020
180 3.120 3.102 .018
178 3.686 3.674 .012
176 4 .324 4 .322 - 0 . 0 0 2
174 5.042 5.050 +0.008
172 5.845 5.865 .020
170 6.734 6.772 038
168 7.716 7.777 Ool
166 8.797 8.885 .088
P . , a t m
1.000
1.183
1.466
1.798
2.179
2.620
3.120
3.686
4 .324
5.042
5.845
6.734
7.716
8.797
9.982
11.280
12.692
14.228
15.892
17.692
19.634
21 .727
23 .981
26 .413
29.034
30.416
31 .853
33.346
34.529
164 9.982 10.101 .119
162 11.280 11.431 151
160 12.692 , 12.880 .188
158 14.228 14.452 .224
156 15.892 16.152 2 D 0
154 17.692 17.985 .293
152 19.634 19.955 .521
150 21 .727 22.066 339
148 23 .981 24.322 .341
146 26 .413 26.727 314
144 29.034 29.284 .250
143 30.416 30.621 .205
142 31 .853 31.996 .143
141 33.346 33.412 .066
140.23 34.529 34.529 .0
- 5 1 -
5. Argon
The deviation curves shown in Figure 13 a r e based on the measu remen t s
of Michels and Levelt (72) and Michels , Wassenaar and Zwietering (21) and on
measu remen t s by Clark, Din and Robb also repor ted in reference (21). The
boiling point of -185.91'*C. is repor ted by Michels (21) and the c r i t i ca l point
of -122.29'*C. and 48.34 a tm. is repor ted by Michels (72). Michels ' vapor-
p r e s s u r e data (72) from 10 a tm. to the c r i t i ca l point lie between his data (72)
and Clark ' s data (21) with a var iat ion of about 0,01 a tm. We have harmonized
Michels ' l a te r h igh -p re s su re data with his ea r l i e r resu l t s to obtain our p r e
fe r red vapor p r e s s u r e s given in Table XII. Michels ' c r i t i ca l constants a r e in
good agreement with the deviation curve . Crommel in (26) has repor ted the
cr i t ica l point to be -122.44' 'C. and 47.996 a tm.
(72) Michels , A . , and Levelt , J . M. , Physica 24, 659(1958).
(21) Clark , A. M. , Din, F , , Robb, J . , Michels , A . , Wassenaar , T, , and
Zwieter ing, Th. N. , Physica 17, 876 (1951).
(26) Crommel in , C. A, , Koninkl. Ned. Akad. Wetenschap. P r o c . Ser . B
22, 1212 (1913) Leiden Comm. Nos. 115a, 138c, 140a.
0.7
0.6
0.5
0.4
^ 0 . 3
d (a
tr
o
P
_
Ar
-
-
-
-
1 -185.91 -180
1 1
C l a r k ^ ^
^
. . . . ^
1 i l l ! -170 -160
Temp (°C) 1 1 1 1
^^//
'^ M̂ ichels
1 1 1 1 -150 -140
1 1
-X _
\ Y \ v \ -
\ -
(
1 1 -122.29
1 0
GLL-637-1706A 20
1
I
40 60 % l /T
Fig . 13. Deviation curve for Ar .
80 100
- 5 3 -
TABLE XII
VAPOR PRESSURE OF Ar
log P j^ = - 3 4 8 . 4 3 2 / T + 3.99395
t , °C. P . , a t m . P ,^ , a t m . d, a t m . 1 is
- 1 8 5 . 9 1
184
182
180
178
176
174
172
170
168
166
164
162
160
158
156
154
152
150
148
146
144
142
140
138
136
134
132
130
128
126
125
124
123
122.29
1.000
1.218
1.484
1.790
2.144
2 .545
3.000
3.513
4 .087
4 .729
5.444
6.232
7.099
8.049
9.085
10.212
11.438
12.766
14.201
15.749
17.415
19.204
21 .119
23 .169
25 .357
27 .687
30.169
32.818
35 .638
38 .631
41 .821
43 .493
45 .227
47 .020
48 .340
1.000
1.218
1.484
1.792
2 .148
2.555
3.018
3.542
4 .131
4 .789
5.522
6.334
7.230
8.214
9.291
10.464
11.739
13.119
14.609
16.212
17.932
19.773
21 .737
23 .829
26 .052
28 .407
30 .899
33.530
36 .301
39 .215
42 .275
43 .859
45 .481
47 .140
48 .340
.0
.0
.0
.002
.004
.0 10
.018
.029
.044
.060
.078
.102
.131
.165
.206
.252
.301
.353
.408
.463
.517
.569
.618
.660
.695
.720
.730
.712
.663
.584
.454
.366
.254
.120
.0
-54-
6. Oxygen
The work of Hoge (50) is considered to be definitive. We have, however,
p repa red a deviation curve based on an ice point of 273.15°K. as compared
to his ice point of 273.16 "K. Hoge has mathemat ical ly fitted his data very
well by connecting separa te equations for each of five tennperature regions .
Our deviation curve shown in F igure 14 r ep resen t s an accuracy within 0.001
a tm. For a c r i t i ca l d iscuss ion of other measu remen t s on oxygen see Hoge's
paper .
(50) Hoge, H. J . , J . Res . Natl. Bur. Std. 44, 321 (1950).
" I—r T r
0 6 0 -
0 4 0 -
E a.
0 2 0 -
Boiling point
I I I I I L
"I I I 1 I } T
-180 -170 J L J L J L J L
160 -150 -140
t(°c) 130
I
I
_U^J \ I L -120 -122 -120 -118
Fig . 14. Deviation curve for O2 vs f C .
- 5 6 - '
T A B L E XIII
V A P O R P R E S S U R E O F Oi
log Pj^ = - 3 6 7 . 3 9 0 / T -f- 4 .07396
I. "G. p . , a t m . Fi^, a t m . d, a t m .
- 1 8 2 . 9 7 1.000 1.000 .0
182 1.105 1.105 .0
180 1.350 1.349 - 0 . 0 0 1
178 1.633 1.632 - 0 . 0 0 1
176 1.960 1.9faO .0
174 2.334 2.336 -fO.002
172 2.760 ^ 2.766 .006
170 3.241 3.253 .012
168 3.780 3.802 .022
166 4 .384 4 .418 .034
164 5.055 5.106 .051
162 5.800 5.870 .070
160 6.623 6.715 .092
158 7.526 7.646 .120
156 8.514 8.668 .154
154 9.594 9.784 .190
152 10.771 11.001 230
150 12.049 12.322 .273
148 13.431 13.752 . .321
146 14.923 15.295 .372
144 16.528 16.954 ,42b
142 18.255 18.735 .480
140 20 .111 20 .641 .530
138 22 .098 22.676 .578
136 24 .224 24.844 .620
134 26.492 27.147 .655
132 28.911 29.589 .678
130 31.486 32.173 .687
128 34 .228 34.902 .674
126 37.147 37.779 .632
124 40 .255 40 .807 .552
122 43 .562 43 .987 .425
121 45 .300 45 .636 .336
120 47 .091 47 .323 .232
119 48 .951 49 .049 +0.098
118.38 50.140 50.139 - 0 . 0 0 1
- 57 -
7. Methane
The v a p o r - p r e s s u r e data repor ted up to 1955 have been cor re la ted by
Arms t rong , Brickwedde, and Scott (6). Since then Hes te rmans and White
(47) have made additional m e a s u r e m e n t s . Along with Arms t rong , Brickwedde,
and Scott 's smoothed va lues , we have presented in F igure 15 the exper imental
measu remen t s of Keyes, Taylor, and Smith (61), Bloomer and Pa ren t s (12),
and Hes te rmans and White. Bennewitz and Andreev (9) have determined only
the cr i t ica l point. Between -162 and -96*'C. Bloomer and P a r e n t ' s resu l t s
a r e in good agreement with A r m s t r o n g ' s cor re la t ion and with A r m s t r o n g ' s
boiling point value of - l 6 l . 4 9 ' ' C . We have given preference to Bloomer ' s
data in drawing the deviation curve because they follow the common fine-
s t ruc tu re pa t te rn . Hes t e rman ' s and White's values general ly para l le l those
of Bloomer and Pa ren t with a p r e s s u r e difference of -0.04 a tm.
Keyes, Taylor, and Smith's data tend to cor robora te A r m s t r o n g ' s and
Bloomer ' s values at lower t e m p e r a t u r e s , but between -96"'C. and the c r i t i ca l
point, the situation is confused. Here A r m s t r o n g ' s cor re la t ion d iverges con
siderably from the exper imental m e a s u r e m e n t s of Bloomer and of H e s t e r m a n s .
This is due most ly to the fact that Arms t rong has used Keyes ' da ta , which ap
pear to be inaccurate in this region, and possibly part ly to the fact that his
type of equation was not sufficiently flexible to produce the curva ture required
to reach the c r i t i ca l point. Arms t rong has recognized in his paper that his
cor re la t ion in the kc region did not fit the accepted c r i t i ca l value, but Bloomer
and P a r e n t ' s data were not available at the t ime of Arms t rong ' s publication.
Three exper imental measu remen t s of the cr i t ica l t empera tu re a r e in fairly
good agreement , as shown in F igu re 15; those of Keyes, Bloomer , and
Bennewitz. It appears to us that B loomer ' s c r i t i ca l t empera tu re of -82.61 "C.
and the corresponding p r e s s u r e of 45.49 a tm. as indicated by the deviation
- 58 -
curve is a good value for the cr i t ica l point. B loomer ' s c r i t i ca l p r e s s u r e is
45.47 a tm. In the light of Hes t e rmans ' and Bloomer ' s data, Kobe and Lynn's
(63) selected value of -82.1 ' 'C. and 45.8 a t m . , which is based on Keyes ' ca l -
culated p r e s s u r e value, is not well founded and indeed confuses the m a t t e r ,
in spite of a seeming numer ica l s imi la r i ty , since in real i ty , this p r e s s u r e is
0.40 a tm. low at the stated t e m p e r a t u r e .
This point is worth emphasizing s ince , had Hes t e rmans ' and Bloomer ' s
m e a s u r e m e n t s not been avai lable , a deviation curve based on Keyes ' vapor-
p r e s s u r e measu remen t s would be so radically different as to c lass methane
with nitrogen and carbon monoxide instead of with oxygen and the noble gases .
(6) Arms t rong , G. T. Brickwedde, F . G. , and Scott, R. B. , J . Res .
Natl. Bur . Std. 55, 39 (1955).
(47) Hes t e rmans , P . , and White. P . , J . Phys . Chem. 65, 362 (1961).
(61) Keyes, F . G. , Taylor , R. S. , and Smith, L. B. , J . Math. Phys . 1,
211 (1922).
(12) Bloomer , O. T. , and Pa ren t , J . D. , Inst. Gas. Techn. Res . Bull.
17 (1952).
(9) Bennewitz, K. , and Andreev, N. , Z. Physik Chem. , AL42, 37 (1929).
(63) Kobe, K, A . , and Lynn, R. E. , J r . , Chem. Rev. 52, 117(1953).
0 80 —
0 6 0
50 40 —
020 —
-160
GLL-633-^^B
^I30 H20 Temperature (°c)
I
I
Fig . 15. Deviation curve for CH4. vs f C .
-60-
TABLE XIV
VAPOR PRESSURE OF CH4
t, ° c .
- 161.49
160
158
156
154
152
150
148
146
144
142
140
138
136
134
132
130
128
126
124
122
120
118
116
114
112
110
108
106
104
102
100
98_
96
94
92
90
89
88
87
86
85
84
83
82 .61
log P ^ =
P j , a t m .
1.000
1.129
1.322
1.541
1.786
2 .054
2 .353
2 .686
3.054
3 .459
3.904
4 . 3 9 1
4 . 9 1 5
5.474
6 .079
6 .734
7 .445
8 .210
9.032
9 .906
10.838
11 .836
12.898
14 .029
15 .229
16 .501
17 .847
19 .268
2 0 . 7 6 0
2 2 . 3 3 4
2 3 . 9 9 4
2 5 . 7 4 4
2 7 . 5 8 8
2 9 . 5 2 7
3 1 . 5 9 1
3 3 . 7 2 3
3 5 . 9 9 2
3 7 . 1 7 1
3 8 . 3 8 2
3 9 . 6 2 9
4 0 . 9 0 4
4 2 . 2 1 3
4 3 . 5 5 7
4 4 . 9 3 8
4 5 . 4 9 0
- 4 4 7 . 2 5 9 / T + 4 . 0 0 5 5 4
P j ^ , a t m .
1.000
1.129
1.322
1.54 1
1.786
2 .059
2.>364
2 .702
3 .076
3 .487
3 .938
4 . 4 3 1
4 . 9 6 8
5 .552
6 .185
6 .868
7 .606
8 . 3 9 8
9 .248
10 .158
11.130
12.166
13 .267
14 .437
15 .676
16 .987
18.371
19 .831
2 1 . 3 6 7
22 .982
2 4 . 6 7 6
26 .452
2 8 . 3 1 2
3 0 . 2 5 5
3 2 . 2 8 3
3 4 . 3 9 9 36 .602
3 7 . 7 3 7
38 .894
4 0 . 0 7 4
4 1 . 2 7 6
4 2 . 5 0 1
4 3 . 7 4 9
4 5 . 0 2 0
4 5 . 5 2 2
d , at2-i-i.
.0
.0
.0
.0
.0
.005
.011
.016
.022
. 028
.034
.040
.053
.078
.106
.134
.161
. 188
.216
.252
.2 92
.330
.3 69
.408
.447
.486
.524
.563
. 6 0 7
.648
.682
.708
.724
. 728
.692
.676
.610
.566
.512
.445
.372
.288
.192
.082
.032
- 6 1 -
8. Nitric Oxide
No h i g h - p r e s s u r e m e a s u r e m e n t s have been made on ni t r ic oxide since
Adwentowski's (2) work in 1909. This is su rp r i s ing , since analysis of his r e
sults indicates that this work fails ser ious ly to mee t modern s tandards of p r e
cision for purity of sample , measu remen t of t empera tu re and p r e s s u r e , and
at tainment of p r e s s u r e and t empera tu re equi l ibr ium. Our deviation curve
shown in Figure 16 is based on Johnston and Giauque's (56) determinat ion of
the boiling point and Adwentowski 's value for the cr i t ica l point. Adwentowski'
data can in no sense be said to de te rmine the deviation curve since alnnost
60% of them do not exhibit any expected consis tent behavior. Never the less ,
a deviation curve consistent with his c r i t i ca l point can be reasonably drawn
through some of his data , this has been done in F igure 16. No conclusions
can be drawn as to the accuaracy of our proposed v a p o r - p r e s s u r e values or
Adwentowski's repor ted cr i t ica l point, and certainly the need for a r e d e t e r
mination of this vapor p r e s s u r e is dictated.
(2) Adwentowski, K. , Intern. Bull. Acad. Sci. Cracovie LLllOg, 742.
(56) Johnston, H. L. , and Giauque, W. F . , J . Am. Chem. Soc. 5j., 3194
(1929).
3-1 3
1.0
0 .8
0 .6
0 . 4
0 .2
0 .2
0 .4
0 .6
—
-
-
—
-
-
-1
151
N O
. 7 4
1
1 1 -140
1 1
• A d w e n t o w s k i
• Gia uque
1
1
_ _ ^
1 -130
T e m p
X
(
L
y X
1
°C)
•
y /
1 -120
1
^
J ^
•
1 1 -110
1 1
— ^ ^ ^
^ V
\
\
]
1 1 -100 - 9 2 . 9
1 1 0 10
GLL-637-1709
20 30 40 60 50
% l / T
F i g . 16. D e v i a t i o n c u r v e fo r NO.
70 80 90 100
I
- 6 3 -
T A B L E XV
V A P O R P R E S S U R E O F NO
leg ^ „ ^ . e ? 3 . 2 7 3 / T + S.S4545
t ,
151.
150
145
140
135
130
125
120
115
110
105
100
95
9 2 .
"C.
74
9
P . , a t m .
1.00
1.23
2.09
3.33
5.00
7.18
10.04
13.81
18.84
25 .41
33.86
44 .53
57.97
64.60
P „ , a t m .
1.00
1.20
1.96
^ 3.08
4.70
6.95
10.02
14.10
19.42
26.23
34.79
45.40
58.37
64.60
d, at:
.0
- 0 . 0 3
. 1 3
. 2 5
. 30
. 2 3
- 0 . 0 2
+0.29
. 5 8
. 8 2
. 9 3
. 8 7
. 40
0
•
- 6 4 -
9. Krypton
The v a p o r - p r e s s u r e deviation curve for krypton shown in F igure 17 is
based on the work of Michels , Wassenaar , and Zwietering (75). The data
ag ree with the deviation curve to within 0.001 a tm. The cr i t ica l t empe ra
ture of Meihuizen and Crommel in (69) of -63.77' 'C. is taken, and the cr i t ica l
p r e s s u r e corresponding to this t empera tu re is 54.31 a tm. This is in good
agreement with Meihuizen's value of 54.270 a tm. The boiling point is due to
Michels (75).
(75) Michels , A . , Wassenaar , T. , and Zwietering, Th. N. , Physica 18
63 (1952).
(69) Meihuizen, J . J . , and Crommel in , C. A. Physica 4, 1 (1937).
0.9
0.8
0.7
0.6
0.5
0.4
I 0.3 o
" " 0.2 •o
0.1
0
Kr
• — • -
-153.401
GLL-637-1710
- • ^
I - 1 4 0
20
I
(Jl
J--130
Temp («C) -no - 9 0
' . ' -63.77
40 60 80 100 % l/T
Fig . 17. Deviation curve for Kr.
-66-
T A B L E XVI
VAPOR PRESSURE O F Kr
log 1 ' , , - - . iM ' i . , ' . iM/ ' i ' I d .O ' ian i
U 'C.
- IS i . - lO
I S i
ISO
148
146
144
142
140
138
136
134
132
130
128
126
124
122
120
I I H
116 114
112
1 10
108
106
104
102
100
98
96
94
92
90
88
86
84
82
80
78
76
74
72
70
68
67
66
65
64
63. 77
P-, a t m .
1.000 1. i 14
1.2 94
1.4 96
1.720
1.969
2.245
2.549
2.883
3.249
3.649
4.084
4.554
5.062
5.611
6.203 6.838
7.521
8.247 9.024
9.857
10.745
11.690
12.695
13.754
14.876
16.062
17.319
18.639
20 .028
21 .485
23 .017
24 .625
26.313
28 .080
29.934
31 .877
33.915
36.047
38.274
40 .603 43 .034
45 .577
48 .226
49 .599
51.015
52.473
53.960
54.306
PpQ, a t m .
1.000
1.114
1.294
1.496
1.72 1
1.972
2.250
2.557
2.895
3.266
3.672
4 .115
4 .596
5.118
5.682
6 .291 6.946
7.651
8.405 9.212
10.073
10.989 11.964
12.999
14.095
15.254
16.478
17.769
19.127
20 .556
22.055
23.627
25.273
26.995
28.793
30.669
32.624
34.660
36 .777
38.976
41 .259 43 .626
46 .078
48 .616
49 .917
51.240
52.585
53.952
54.270
cl. ;itn\
.0
.0
.0
.0
.001
.003
.005
.008
.012
.017
.023
.031
.042
.056
.071
.088
.108
.130
.158
. 188
.216
.244
.2 74
.304
.341
.376
.416
.450
.488
.528
.5 70
.610
.648
.682
.713
.735
.747
.745
.730
.702
.656
.592
.501
.390
.318
.225
f 0 . 1 1 2
- 0 . 0 0 8
- 0 . 0 3 6
-67 -
10. Xenon
The deviation curve for xenon shown in F ig . 18 is based on the data
of Michels and Wassenaar (73). The data ag ree with the curve within 0.001
a tm. Pa t t e r son , Cr ipps , and Whytlaw-Gray (89), and Weinberger and
Schneider (113) have both found the cr i t ica l t empe ra tu r e to be 16.59"'C.
The corresponding vapor p r e s s u r e from our cruve is 57.64 a tm. Habgood and
Schneider (45) have reported the c r i t i ca l p r e s s u r e to be 57.636 a tm. The boil
ing point is due to Michels (73).
(73) Michels , A . , and Wassenaar , T. , Physica ^ , 253 (1950).
(89) Pa t t e r son , H. S. , Cr ipps , R. S. , and Whytlaw-Gray, R. , P r o c . Roy.
Soc. (London) A86, 579 (1912).
(113) Weinberger , M. A . , and Schneider, W. G. , Can. J . Chem. 30, 422
(1952).
(45) Habgood, H. W. , and Schneider, W. G. , Can. J . Chem. 32, 98 (1954).
0.9
0.8
0.7
0.6
0.5
04
I 0.3 o
0.1
0
Xe
-105.121-iooT
" • 9r
I
00 I
:i ^̂ 8D^ X
Temp (*'C) -40
J L -20
I . I 0 116.59
20 40 1 60 80 100
GLL-637-1711 % I /T
Fig . 18. Deviation curve for Xe.
- 6 9 -
I. 'C
108.12
108
106
104
102
100
98
96
94
92
90
88
86
84
82
80
78
76
74
72
70
68
66
64
62
60
58
56
54
52
50
48
46
44
42
40
T A B L E XVII
V A P O R P R E S S U R E O F Xe
log Pj^ = - 6 7 4 . 9 7 4 / T + 4 .09000
P i , a t m . P j^ , a t m . d, a t m .
1.000 1.000 .0
1.007 1.007 .0
1.128 1.127 - 0 . 0 0 1
1.260 1.258 .002
1.403 1.400 .003
1.559 1.555 .004
1.728 ' 1.723 .005
1.910 1.905 .005
2.106 • 2 .101 .005
2.317 2.312 .005
2.541 2.539 - 0 . 0 0 2
2.783 2.783 .000
3.041 3.044 +0.003
3.316 3.323 .007
3.609 3.621 .012
3.922 3.940 .0 18
4.254 4 .278 .024
4.608 4 .638 .030
4.984 5.020 .036
5.381 5.425 .044
5.801 5.854 .053
6.243 6.307 .Ob4
6.710 6.786 .076
7.203 7.291 .088
7.720 7.822 .102
8.265 8.382 .117
8.836 8.970 .134
9.435 9.587 .152
10.062 10.234 .172
10.720 10.912 .192
11.407 11.621 ^ .214
12.125 12.363 .238
12.874 13.137 .263
13.658 13.946 .288
14.475 14.789 .314
15.323 15.667 .344
- 70 -
TABLE XVII (Continued) P , atm.
1 16.205
17.1 19
18 0 74
19.067
20.099
21.170
22.282
23.434
24.D2O
25.861
27.140
28.464
29.836
31.255
32.722
54.236
35.801
37.416 39.082
40.802
42.584
44.425
45.367
46.326
47.299
48.288
49.295
5C.325
51.372
52.450
53.546
54.660
55.793
56.950
57.639
P , atm.
16.58J
17.'̂ ^ 1
18.519
19.544
20.608
21.711
2^.854
24.038
25.2o2
26.528
27.836
29.186
30.580
32.017
33.498
35.024
36.595
38.212 39.875
41.584
43.340 Hi
45.143
46.062
46.994
47.937
48.892
49.859
50.839
51.830
52.834
53.850
54.878
55.919
56.972
57.599
d, atn
3 76
1 1..
44 S
4"? .5 0'"̂
o4
57„
D04
>36
^ D07
o96
.7^2
.744
.762
.77o
.788
.794
.796
.793
782
.756
.7 18
.o95
.OD8
028
.o04
.5b4
5 i4
.458
384
304
.2i8
.126
+0.022
-0.040
- 7 1 -
11. Silicon Tetrafluoride
The deviation curve in F igure 19 for silicon te t raf luoride is based on
the data of Patnode and Papish (88), and Booth and Swinehart (13). The t r ip le
point and cr i t ica l p roper t ies a r e due to these au thors . Patnode and Pap ish ' s
points appear to be fairly consistent although not of the highest prec is ion .
Only about half of Booth and Swinehart 's data approach the expected deviation
curve , and, in addition, no data a r e available for the center portion of the
curve between -75 and -40 ' 'C. The rel iabi l i ty of the vapor -p res su re values
above -75 ' 'C. i s , therefore , probably not be t ter than ±0.05 a tm.
(88) Patnode, W. I. , and Papish , J . , J . Phys . Chem. 34, 1494 (1930).
(13) Booth, H. S. , and Swinehart, C. F . , J . Am. Chem. Soc • 57, 1337
(1935).
0.7
0
GLL-63T-1712
20
- J rsj I
- 6 0 TempC^C)
H4.I7
40 6 0 80 100 % l /T
Fig . 19. Deviation curve for S iF^ .
- 7 3 -
TABLE XVIII
VAPOR PRESSURE OF SiF^
l og P ^ = - 8 8 8 . 7 4 3 / T + 4 .99589
t, ° c .
90.2
90
85
80
75
70
65
60
55
50
45
40
35
30
25
20
15
14.17
P., atm.
1.756
1.781
2.500
3.351
4.35
5.52
6.86
8.40
10.14
12.12
14.35
16.87
19.72
22.94
26.60
30.80
35.72
36.66
P„, atm. is.
2.076
2.098
2.720
3.479
4.396
5.490
6.783
8.299
10.059
12.089
14.411
17.051
20.032
23.380
27.116
31.267
35.854
36.660
d, atm
+0.320
.317
.220
.128
+ 0.047
-0.027
.080
.100
.082
-0.028
+ 0.062
179
.3 10
.442
5 12
.4b5
il'O
0
•
" 7 4 -
12. Nitrous Oxide
The v a p o r - p r e s s u r e data of Hoge (49) and Couch and Kobe (24) have
been used to der ive the deviation curve shown in Figure 20. Our deviation
curve was drawn to a prec is ion of 0.001 a tm. and appears to agree quite well
with the data except for Couch's point at 35.5' 'C. , which is high. The boi l
ing point and cr i t ica l point values quoted a r e the above au thors ' exper imental
va lues .
(49) Hoge, H. J . , J . Res . Natl. Bur. Std. 34, 281 (1945).
(24) Couch, E. J . , and Kobe, K. A . , J . Chem. Eng. Data 6, 229 (1961).
0.3
0.2
0.1
0<
io.i 3 0.2
" ^ 0 . 3
-
-
-
-
1 -88.46|-80
1
N2 0
• Hoge
• Couch
^ " ^ ^ ^ " " " ^ - ^ ^ . ^
1 1 1 1 1 -60 -40
Temprc) 1 1 1 1 1
y
1 -20
1
^
/
/
/
1 0
1
/ \
/ \
J —
1 1 1 1 3443
1 20
GLL-637-1713
I -vl
I
40 60 80 100 % I / T
Fig . 20. Deviation curve for N2O.
= 76-
T A B L E XIX
VAPOR P R E S S U R E O F N2O
log P j . = - 8 4 9 . 1 2 2 / T + 4 .59767
t, "C.
- 8 8 . 4 6 5
88
86
84
82
80
78
76
74
72
70
68
66 64
62
60
58
56
54
52
50
48
46
44
42
40
38
36
34
32
30
28
2o
24
22
20
P^, a t m .
1.000
1.028
1.156
1.297
1.452
1.620
1.804
2.003
2.217
2.451
2.702
2.971
3.260
3.571
3.903
4 .258
4 .637
5.042
5.472
5.929
6.414
6.928
7.470
8.045
8.651
9.291
9.965
10.675
11.421
12.207
13.031'
13.894
14.800
15.746
16.738
17.774
P ^ . a t
1.000
1.027
1.150
1.284
1.431
. 1.590
1.764
1.953
2.157
2.379
2.618
2.875
3.152
3.450
3.769
4 .111
4 .477
4 .868
5.285
5.729
6.202
6.704
7.236
7.801
8.399
9.031
9.698
10.403
11.145
11.927
12.750
13.614
14.522
15.474
16.472
17.516
-77 -
TABLE XIX (Continued)
18. 857
19.986
21.163
22.388
23.663
24.995
26.378
27.815
29.309
30.861
32.474
34.147
35.883
37.682
39.545 41.474
43.474
45.550
47.704 49.934
52.242
54.629
57.101
59.661
62.311
63.671
65.064
66.483
67.936
69.418
70.931
71.596
18.610
19.752
20.946
22.192
23.491
24.846
26.25b
27.723
29.249
30.835
32.482
34.191
35.963
37.800
39.703 41.674
43.712
45.820
47.999 50.249
52.572
54.969
57.441
59.989
62.614
63.956
65.318
66.699
68.100
69.522
70.964
71.596
-0.247
.234
.217
.196
.172
.149
.122
.092
.060
-0.026
+ 0.008
.044
.080
.118
.158
.200
.238
.270
.295
.315
.330
.340
340
.328
.303
.285
254
.216
.lb4
.104
.033
.0
-78-
13. Carbon Dioxide
The most re l iable and consistent measu remen t s of CO^ a r e those of
Michels , Wassenaar , Zwietering, and Smi t s (77) and Meyers and Van Dusen
(70).
The t r iple-point value of -56.573 "C. and 5.116 a tm. is due to Michels .
Meye r s ' value of -56.60°C. and 5.112 a tm. differs from Michels ' p r e s s u r e of
5.110 a tm. at -56.60°C. by +0.002 a tm. Between the t r ip le point and +3°C. ,
Michels ' and Meye r s ' data a r e in good agreement . F r o m this point to the
cr i t ica l point, the data of Michels , B la i s se , and Michels (71), de termined in
1936, a r e in radica l d i sagreement both with Meye r s ' resu l t s and with their
la te r work cited above. Unfortunately, Michels ' la ter paper does not resolve
this contradict ion. The m e a s u r e m e n t s of Roebuck, Mur re l l , and Miller (101)
in the range from -20°C. to the c r i t i ca l , while not to as high a degree of a c
curacy as the work of Meyer s , well support his data, as compared to those of
Michels , B la i s se , and Michels . Because , as is shown in Table XX, Wentorf 's
(114) measu remen t of the cr i t ica l point excellently confirms Michels ' va lues ,
we have adjusted the deviation curve between 20 "C. and the c r i t i ca l point to
conform to this value ra ther than Meyer s ' value.
The values in Table XX were obtained from the l a r g e - s c a l e plot of the
region between 20.0 and 31.1°C. drawn in F igure 21. It can be seen from
Figure 21 that Michels ' repor ted p r e s s u r e of 72.85 a tm. at 31.04°C. is higher
than that obtained from a smooth curve through his points at 29.929, 30.409,
and 31.0 13 "C. F r o m this curve , we obtained a p r e s s u r e of 72.842 a tm. as
compared to Wentorf's reported value of 72.839 a tm. Meyers ' value of 72.800
a tm. is also seen from the plot to be about 0.005 a tm. below the mean of his
values through the c r i t i ca l region. Additional cr i t ica l data (106, 67, 3) a r e
also given in Table XX. Figure 22 is a plot of the deviation curve on a %(1/T)
b a s i s .
- 7 9 -
(77) Michels , A . , Wassenaar , T. , Zwietering, Th. N. , and Smits , P . ,
Physica 16, 501 (1950).
(70) Meye r s , C. H. , and Van Dusen, M. S. , J . Res . Natl. Bur. Std. 10,
381 (1933).
(71) Michels , A . , B la i s se , B. , and Michels , C , P r o c . Roy. Soc. (London)
A160, 358 (1937).
(101) Roebuck, J . R. , Mur re l l , T. A . , and Mi l le r , E. E . , J . Am. Chem.
Soc. 64, 400 (1942).
(114) Wentorf, R. H. , J r . , J . Chem. Phys . 24, 607 (1956]^.
(106) Schmidt, E . , and Thomas, W. , F o r s c h . Gebeite . Ingeniurw 20jB, 161
(1954).
(67) Lorentzen, H. C , Acta Chem. Scand. 7, 1335 (1953).
(3) Ambrose , D. , Trans Faraday Soc. 52, 772 (1956).
TABLE XX
CRITICAL PROPERTIES OF CO2 AS MEASURED BY
VARIOUS INVESTIGATORS
Observer
Meyers
Michels
Wentorf
Schmidt and Thomas
Lorentzen
Ambrose
Reported
Tc
31.00
31.04
31.04
31.01
31.04
31.01
P c
72.80
72.85
72.839
72.50
F r o m
Tc
31.00 31.04
31.04
F r o m deviation curve plot
72.805 72.872
72.842
0 40
0 30
^ 2 0
E 3 T3
0 10
0
1
•
-
•
~_
~
-
-
1 20
CO 2 • Miche ls
• Meyers
• Roe buck
» Cr i t ica l point
1 I 1 22
'
•
! 24
1 *
•
• t •
1 1
X
1 26
1
^ v •
\ ^ ^y
\ • \
1 28
1 1
-
-
~
_
\ •
1 \
• \
\vVentorf • '^Michels
• Meyers \f
•
1 1 30
GLL-633-445A Temperature (°c)
F ig . 21 . Deviation curve for CO2 vs t °C . from 20 °C. to the cr i t ica l point.
00 o
s . 4 - 1
0.5
0.
0.3
0.2
0.1
0
•0.1
•0.2
• 0 . 3 -
C O .
-bb.bU|-50
0 GLL-637-1714
10
^ M i c h e l s
• M e y e r s
•Roebuck
- 4 0 ^ — r i ^ T e m p ( ° C )
10 10
± 20 30 40 50
% l / T 60 70 80
00
31.04
90 100
F i g . 22 . D e v i a t i o n c u r v e for CO2 vs % ( 1 / T ) .
- 8 2 -
T A B L E XXI
VAPOR P R E S S U R E O F CO^
itif. 1 -̂., - .Hbi.i^i/r I 4.ili'i(t
l . ° C
S6. S73
S4
S.!
SO
' !8
•4 6
•44
•42 40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
- 2
0
+ 2
4
6
8
10
12 14
16 13
20
22
24
26
27
28
29
30
31 31.04
P j , a i m .
S.116
S.71 1
6.210
6.740
7.302
7.901
8 .536
9.209 9.918
10.668
1 1.457
12.290
13.166
14.089
15.059
16.078
17.146
18.265
19.436
20 .662
21 .944
23 .283
24 .679
26 .135
27 .655
29 .239
30 .890
32 .606
34.392
36 .249
38 .179
40 .184
42 .265
4 4 . 4 2 7
4 6 . 6 7 1
48 .999
51 .414 53 .920
56 .521
59 .221
62 .024
64 .936
66 .439 67 .972
69 .537
71 .138
72 .773 72 .840
P j ^ , a t m .
5.118
5.70 3
6 .193
6.715
7.270
7.861
8 .488
9^ 1 5 3 9 .857
10.602
11.389
12.220
13.096
14.019
14.990
16.012
17.085
18 .211
19.391
20 .628
21 .923
23 .277
24 .692
26 .169
2 7 . 7 1 1
29 .318
30 .993
32 .736
34 .550
36 .435
38 .395
4 0 . 4 2 9
4 2 . 5 3 9
4 4 . 7 2 8
4 6 . 9 9 6 4 9 . 3 4 5
51 .777
54 .292
56 .893
59 .581
62 .357
65 .222
66 .689
68 .179
69 .692
71 .228
72 .787 72 .850
d , a t m
40 .002
- 0 . 0 0 8
.017
.025
.032
.040
.048
.056
.061
.066
.068
.0 70
.070
.070
.069
.066
.061
0 54
045
034
.02 1
- 0 . 0 0 6
+ 0.013
.034
.056
.079
.103
.130
.158
.186
.216
.245
.274
.301
.325
.346
.363
.372
.372
.360
.333
.286
.250
,207
.155 " .0 90
.014
.010
- 8 3 -
^^' Hydrogen Chloride
The data of Thomas (109a) and of Cardoso and Germann (19), between
-30 and 50 "C. appear to be in d i sagreement by a constant sys temat ic e r r o r
as seen in Figure 23. The deviation curve has been located to correspond
to Thomas ' data because his work is more recent and appears to give the most
consistent agreement with the other hydrogen halide curves shown in Figure
3. Thomas has measured a cr i t ica l t empera tu re of 51.54 "C. and calculated
a c r i t i c a l - p r e s s u r e of 81.97 a tm. from his v a p o r - p r e s s u r e equation. We
have found a c r i t i ca l p r e s s u r e value of 82.07 to be in be t te r ag reement with
out deviation curve . This difference is at tr ibuted to the inability of Thomas '
equation to follow the curvature of the v a p o r - p r e s s u r e curve near the cr i t ica l
point. Cardoso and Germann (18) reported cr i t ica l point values of 51.4°C.
and 81.55 a tm. Kopper (64) has measu red a value of 51.0 °C. for the c r i t i ca l
t empe ra tu r e . Giauque and Wiebe's (39) measu remen t s have been used to lo
cate the deviation curve in the vicinity of the boiling point.
(109a) Thomas, W. , P rog . Intern. Res . Thermodynamic Transpor t P r o p e r
ties ASME Second Symposium, 1962.
(19) Cardoso, E . , and Germann, A. F . O. , J . Chim. Phys . U, 632(1913).
(18) Cardoso, E. , and Germann, A. F . O. , J . Chim. Phys . 10, 517 (1912).
(64) Kopper, H. , Z. Physik. Chem. A175, 469 (1936).
(39) Giauque, W. F . , and Wiebe, R. , J . Am. Chem. Soc. 50, 101 (1928).
0.8
0.6
0.4
0.2
0.2
1
HCl
CARDOSO THOMAS GIAUQUE
1 TEMPERATURE r O J \ \ L.
•85.03! -70 -50 -30 J L
20 GLL-63T-1715A
40 60 % I/T
80
00
I I \ \ i _ a 30 51.54
100
Fig . 23. Deviation curve for HCl.
- 8 5 -
T A B L E XXII
V A P O R P R E S S U R E O F HCl
log P :- -856.120/T + 4.55093
P . . a tm . P ^ , a tm. d, atm
1.00
LOO
1.32
1.72
2.20
2.78
3.47
4 .29
5.25
6.37
7.65
9.12
10.79
12.68
14.79
17.15
19.74
22.62
25.80
2 9 . 3 1
33.18
37.42
42 .05
47 .09
52.57
58.50
64 .91
71 .91
79.56
82.07
1.000
1.002
1.314
1.700
2 .171
2 .741
3.423
4 . 2 3 1
5 .181
6.288
7.568
9.038
10.714
12.616
14.759
17.162
19.842
22 .816
26.102
29.718
33.680
38.005
42 .708
47 .807
53.315
59.248
65.619
72.443
79.732
82.073
.000
.000
- 0 . 0 0 8
.018
.025
.038
.050
.060
.070
.078
.080
.080
.075
.060
- 0 . 0 3 2
+0.015
.100
.200
.305
.405
.500
.590
.660
.714
.744
.747
.710
.530
.170
.0
-86 -
15. Hydrogen Bromide
The only data available for HBr a r e those of Drozdowski and P ie t rzak
(28), whose m e a s u r e m e n t s on HCl a r e in very poor agreement with our curve
for HCl. Never the less , the points shown for HBr appear to agree fairly well
with the projected curve shown in Figure 24 and Giauque and Weibe's boiling
point value (40). The cr i t ica l t empera tu re determined by Kopper (64) is
89.9' 'C. , by Moles (81) 89.8°C, and by Drozdowski and P ie t rzak 90.0' 'C. We
have used 90.0' 'C. and found the corresponding p r e s s u r e to be 84.5 a t m . ,
which is in good agreement with Drozdowski 's value of 84.44 a tm.
(28) Drozdowski, E. , and P ie t rzak , J . , Bull. Intern. Acad. Sci. Cracovie
A 1 9 n , 219.
(40) Giauque, W. F . , and Wiebe, R. , J . Am. Chem. Soc. 50, 2193 (1928).
(64) Kopper, H. , Z. Physik. Chem. A. 175, 469 (1936).
(81) Moles , E. , J . Chim. Phys . 17, 415 (1919).
-66.72 -50
1
00
I
-30 -10 10 TEMPERATURE (*»C)
0 10 20 G]aL-63T-lTl6A
30 4 0 50 % l/T
60 70 80 90 100
Fig . 24. Deviation curve for HBr.
- 8 8 -
TABLE XXIII
VAPOR PRESSURE OF HBr
log P j^ = - 9 2 1 . 6 8 7 / T + 4 .46489
t , ° C . P^ . a t m . P ^ , a t m . d, a t m .
66 .72
65
60
55
50
45
40
35
30
25
20
15
10
- 5
0
+ 5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90.0
1.000
1.09
1.39
1.76
2.20
2.72
3.32
4 .03
4 .85
5.78
6.84
8.02
9.35
10.81
12.44
14.23
16.20
18.36
20 .73
23 .33
26 .18
29 .27
32 .64
36.30
40 .25
4 4 . 5 1
49 .10
54.02
59.28
64 .91
70.94
77.43
84.50
1.000
1.089
1.383
1.737
2.160
2 .661
3.249
3.933
4 .724
5.632
6.668
7.844
9.170
10.658
12.320
14.166
16.210
18.461
20 .932
23 .634
26 .578
29 .775
33 .236
36.972
40 .992
45 .306
49 .924
54.855
60 .108
65 .691
71.612
77.880
84.500
.0
.0
- 0 . 0 1 0
.020
.035
.055
.075
.100
.125
.150
.170
.180
.180
.155
.120
- 0 . 0 6 0
+0.010
.105
.200
.300
.400
.502
.600
.675
.740
.796
.823
.840
.828
.785
.670
.450
.0
- 8 9 -
16. Sulfur Hexafluoride
The deviation curve for SF/ shown in F igure 25 is based on the t r ip le
point of 2.20 a tm. at -51 °C. determined by Mi l le r , Verdell i , and Gall (79)
and a c r i t ica l point of 37.193 a tm. at 45.642 "C. de termined by Wentorf (114).
Unfortunately, t he re a r e no data of comparable rel iabi l i ty between these two
t e m p e r a t u r e s . The average of Mi l l e r ' s liquid v a p o r - p r e s s u r e m e a s u r e m e n t s
from -50 to 0°C. does not show the expected negative region for the deviation
curve and does not match Clegg, Rowlinson, and Sutton's (23) 0 and 10 °C.
points . Because of the s imi lar i ty of its coexistence line with that of S F , ,
it was expected that the normal ized CO-, curve might well r ep re sen t the S F ,
data; and, as shown in Figure 25, it indeed fits Clegg's data fairly well. On
this bas is we have used this curve for SF/ in the -51 to 30 "C. region as shown
in Figure 1 above. Otto and Thomas ' (87) data a r e suspect between 0 and
20 "C. because they do not predict a negative deviation region below O^C. a n d a r
evidently in e r r o r above 30 "C. , where the exhibit a "nose" effect in d i s a g r e e
ment with Clegg's data . Near the cr i t ica l point the measu remen t s of both
Otto and Clegg agree with Wentorf 's c r i t ica l point.
(79) Mil ler , H. C , Verdell i , L. S. , and Gall, J , F . , Ind. Eng. Chem. 43
1126 (1951).
(114) Wentorf, R. H. , J r . J . Chem. Phys . 24, 607 (1956).
(23) Clegg, H. P . , Rowlinson, J . S. , and Sutton, J . R. , T r a n s . Faraday
Soc. 5J, 1325 (1955).
(87) Otto, J . , and Thomas, W. , Z. Physik. Chem. (Frankfurt) 23, 84 (I960).
90-
O
o
o
CO
o
o
ID
O
in
o
5t
o 1-\ 55
v£) h
C
fi
u
0 OJ
> u
11
0 .f-( •i->
a > (U
p
in
ro
O
_ O
10
0 ^ 0
ro
0 C
J
0 ~
0 -
0 0 1
(UJ4D
)P
CM
0 1
ro
0 1
^ 0 1
10 0 1
H
- 9 1 -
T A B L E XXIV
VAPOR P R E S S U R E O F S F
log P = - 8 9 9 . 3 3 5 / T + 4 .39153
t , "C.
- 5 1
50
45
40
35
30
25
20
15
10
- 5
0
+ 5
10
15
20
25
30
35
40
45
45.64
P . , a t m .
2.20
2.30
2.84
3.46
4 .18
5.00
5.93
6.97
8.15
9.46
10.92
12.53
14.32
16.28
18.43
20.80
23.40
26.26
29.39
32.82
36.64
37.19
P j ^ , a t m .
2 .204
2.298
2.816
3 .421
4 .123
4.930
5.853
6.902
8.086
9.418
10.906
12.562
14.396
16.419
18.641
21.072
23.722
26 .601
29.719
33.085
36.708
37.191
d, a t m
.000
- 0 . 0 0 4
.022
.038
.053
.066
.073
.072
.062
.042
-0 .010
+0.032
.080
.138
.208
.273
.324
.343
.330
.265
.070
.0
-92 -
17. Hydrogen Sulfide
The h igh -p re s su re data for H-,S in the l i t e ra tu re do not extend below
O'C. The measu remen t s of Reamer , Sage, and Lacey (95) and Kay and
Rambosek (58) ag ree to bet ter than 0.1 a tm. below 70 "C. , as shown in F igure
26. Above 70 "C. R e a m e r ' s points r ep re sen t vapor p r e s s u r e s which a r e lower
by 0.2 to 0.3 a tm. Most of Cardoso ' s (15) measu remen t s a r e sys temat ical ly
lower by 0.5 a tm. than those of Reamer and of Kay. F igure 23 shows a s i m i
lar difference between Cardoso ' s and Thomas ' data for HCl. We have based
our deviation curve on Kay and Rambosek 's data because they a r e m o r e com
plete than R e a m e r ' s in the jhk region and because R e a m e r ' s measu remen t s
in the kc region appear to exhibit a "nose" effect. R e a m e r ' s points shown
in F igure 26 a r e comprised of three published experimental points and three
o thers kindly supplied to us by him. We have not used any of R e a m e r ' s pub
lished smoothed points since he has stated that they a r e of poorer prec is ion .
It is r emarkab le that our vapor p r e s s u r e values shown in Table XXV agree
within 0.1 a tm. with Cragoe ' s (54) smoothed points published in 1928.
Giauque and Blue (34) and Clark, Cockett, and Eisner (22) repor t boil
ing points of -60.33 and -60.19' 'C. , respect ive ly . Kopper (64) has determined
a cr i t ica l t empera tu re of 100.1°C. and Cardoso repor t s a cr i t ica l point of
100.4''C. and 88.90 a tm. Kay and Rambosek 's cr i t ica l point of 99.92°C. and
88.26 a tm. ag rees well with our deviation curve .
(95) Reamer , H. H. , Sage, B. H. , and Lacey, W. N. , Ind. Eng. Chem.
42, 140 (1950).
(58) Kay, W. B. , and Rambosek, G. M. , Ind. Eng. Chem. 22J (1953).
(15) Cardoso , E. , Gazz. Chim. Ital. 51, 1 (192 1).
- 93 -
(54) "International Cri t ical T a b l e s , " Vol. Ill, McGraw-Hil l Book Company,
Inc . , New York, 1928, pp. 201-249.
(34) Giauque, W. F . , and Blue, R. W. , J . Am. Chem. Soc. 58, 831 (1936).
(22) Clark, A. M. , Cockett, A. H. , and E i sne r , H. S. , P r o c . Roy. Soc.
(London) A209, 408 (1951).
(64) Kopper, H. , Z. Physik. Chem. AJ175, 469 (1936).
1.0
0 8
0.6
0.4
0.2
0
0 2
- HgS
—
1 -60.19!
A CARDOSO • REAMER • KAY
^ ^ ^
1 1 1 1 -^O -20
> ^ •
1 0
A
1 20
A
A A
I
/
7
1 1
40
A - A A
A A
/ \
/ • \
1
1 1 i 1
60 80 99.9 1
0 GLL-63T-1718B
20 40 60
TEMPERATURE CO % l/T
Fig . 26. Deviation curve for H2S.
80 100
55
50
45
40
35
30
25
20
15
10
-5
0
+ 5
10
15
20
25
30
40
50
55
60
65
70
75
80
85
90
95
-95-
TABLE XXV
VAPOR PRESSURE OF H^S
t ' °C. P., atm. P^, atm. d, atm.
•60 .19 1.00 1.000 .0
60 1.01 1.009 - 0 . 0 0 1
l o g P j , - -
p . , a t m . 1
1.00
1.01
1.38
1.64
2.04
2.53
3.10
3.76
4 .52
5.38
6.38
7.50
8.77
10.19
11.77
13.52
15.45
17.57
19.89
22 .44
2 5 . 2 1
28 .22
31 .49
3 5 . 0 1
38.83
4 2 . 9 4
47 .35
52 .07
57.13
62 .55
68 .34
74.56
81 .22
88 .26
965 .518 + 4 .53380
P „ , a t m
1.000
1.009
1.282
1.611
2 .004
2.470
3.017
3.655
4 .395
5.245
6 .218
7.324
7.573
9 .978
11.550
13.301
15 242
17.386
19.744
22 .328
25 .149
28 .220
3 1 . 5 5 1
35.153
39 .038
4 3 . 2 1 7
47 .698
52 .494
57.613
63 .064
68 .858
7 5 . 0 0 1
81 .504
88 .260
.010
.025
.040
.060
.080
.100
.120
.140
.160
.180
.200
.210
.220
.220
.210
.185
.150
.110
35 2 5 . 2 1 25 .149 - 0 . 0 6 0
.000
45 31 .49 3 1 . 5 5 1 +0 .065
.140
.2 10
.280
.350
.420
.480
.510
.510
.440
.280
99.92 88 .26 88 .260 .000
-96 -
18. Hydrogen Iodide
As is the case of HBr, the only data for HI have been determined by
Drozdowski and P ie t rzak (28). The deviation curve shown in F igure 27 is
drawn to fit Giauque and Wiebe's boiling point (41) and matches the deviation
curve pat terns shown in Figure 3. Drozdowski 's points in the k region of
the curve a r e much too low to fit the curve and have been d i scarded . The
c r i t i ca l t empera tu re used, 1 5 0 . T ' C , is that of Kopper (64). The correspond
ing p r e s s u r e is 81.9 a tm. Drozdowski and P i e t r zak ' s cr i t ica l values a r e
150.0 "C. and 80.8 a tm.
(28) Drozdowski, E. , and P ie t rzak , J . , Bull . Intern. Acad. Sci. Cracovie
A 1 9 n , 219.
(41) Giauque, W. F . , and Wiebe, R. . J . Am. Chem. Soc. 5J, 1441 (1929).
(64) Kopper. H. , Z. Physik. Chem. A175, 469 (1936).
-35.35 -20 0 20 40 60 TEMPERATURE (•C)
I \ I
150.7
10 GLL-637-1719A
20 30 40 50 % l /T
60 70 80 90 100
Fig . 27. Deviation curve for HI.
- 98 -
TABLE XXVI
VAPOR PRESSURE OF HI
log P ^ = - 1 0 3 6 . 5 1 / T + 4.35875
t, "C.
-35 .35
35
30
25
20
15
10
- 5
0
+ 5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
130
135
140
145
150
150.7
l o g JT-j, - - l U J U
P . , a t m . 1
1.00
1.02
1.26
1.54
1.87
2.26
2.70
3.19
3.76
4.41
5.12
5.93
6.82
7.81
8.90
10.09
11.40
12.83
14.38
16.06
17.86
19.80
21.88
24.10
26.48
29.01
31.72
34.61
37.69
40.96
44.45
48.15
52.09
56.25
60.64
6 5 . 2 8
70.19
75.46
81.09
81.90
. J 1 / J. T T . J_ '*J 1 ~>
P „ , a t m .
1.000
1.015
1.247
1.520
1.838
2.206
2.630
3.114
3.665
4.288
4.990
5.776
6.652
7.626
8.702
9.887
11.189
12.613
14.165
15.852
17.681
19.656
21.785
24.074
26.528
29.152
31.954
34.937
38.107
41.470
45.031
48.793
52.761
56.941
61.335
65.949
70.785
75.847
81.139
81.898
d, a t m
.0
.0
-0 .0 10
.020
.035
.050
.065
.080
.100
.120
.135
.150
.165
.180
.195
.205
.215
.220
.220
.205
.180
.140
.090
-0 .025
+0.050
.140
.230
.330
.420
.510
.581
.640
.670
.690
.691
.665
.595
.385
.045
.0
-99-
19. Chlorine
Knietsch (62) and Pellaton (90) have both measured the vapor p r e s s u r e
of CK between the boiling point and the c r i t i ca l point. Knietsch's resu l t s a r e
considered to be general ly unrel iable since below O^C. they show a high p r e s
sure "nose" and above 40 °C. they diverge steeply in the high p r e s s u r e d i
rect ion. Pel la ton 's values a r e f ragmentary and not too consistent between 80
and 100 "C. However, in general they fit the projected curve fairly well.
Giauque and Powel l ' s value (37) has been used for the boiling point. The
deviation curve for Cl^ is shown in F ig . 28.
(62) Knietsch, Ann. Chem. 259. 100 (1890).
(90) Pel laton, M. , J . Chim. Phys . 13, 426 (1915).
(37) Giauque, W, F . , and Powell , T. M. , J . Am. Chem. Soc. 6J., 1970
(1939).
10
0-
•
• (
• v
• N
CM
O
1 1
r-̂^*^
•
\^
X
o
CO
1-UJ
z ^ •
1
s^
o
H
< _I
_l
LU
Q.
• 1
• •
•
\
•J i •
^1 •P
Jl
/ •
/• /
•
/ H
/•
—
—
^^
—
—
—
^_
—
_ — o
o
(Oo) 08 09 °^ 3 —
1-<
ott:
CV
IUJ
CL
-
0 0 TEM
1 1
CM
1
lO
o •
lO
1
o
o
o 0
)
o 00
o o CD
o lO
t—I
u u
o >
u
u
0 • rH
•4->
> O
>$
P
o
s
00
•i-i
<: o
C5
<J> 00
N
• •
•
oo
o
CD
lO
^ to
CM
—
O
d
o
d
d
d
d
(UJ
|D)p
CM
P
6
- 1 0 1 -
TABLE XXVII
VAPOR PRESSURE OF CI2
log P^ = - 1 0 5 3 . 4 5 / T + 4 .40590
t , " C .
- 3 4 . 0 5
30
25
20
15
10
- 5
0
+ 5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
130
135
140
144.12
P . , a t m .
1.00
1.19
1.47
1.79
2.15
2 .58
3.07
3.62
4 .25
4 .95
5.74
6.61
7.59
8.66
9.85
11.15
12.57
14.11
15.78
17.58
19.53
21 .62
23 .86
26 .28
28 .86
31 .63
34 .59
37 .76
4 1 . 1 4
44 .74
48 .56
52.62
56.92
61 .49
66 .34
71.52
76.10
P , a t m .
1.000
1.184
1.448
1.756
2 .114
2 .527
3 .001
3.542
4 .155
4 .846
5.623
6.492
7 .458
8.529
9 .711
11.012
12.437
13.994
15.690
17.531
19.524
21 .675
2 3 . 9 9 1
2 6 . 4 7 8
29 .143
3 1 . 9 9 1
35 .029
38 .262
4 1 . 6 9 7
4 5 . 3 3 7
4 9 . 1 8 9
53 .258
57 .549
62 .066
66 .813
71 .796
76 .081
d, a t m .
0 .000
- 0 . 0 1 0
.019
.029
.040
.053
.067
.080
.095
.106
.115
.120
.128
.132
.135
.137
.130
.119
.092
.052
- 0 . 0 0 3
+0.060
.130
.203
.285
.362
.435
.500
.555
.600
.630
.640
.630
.576
.470
+0.280
- 0 . 0 1 9
-102-
20. Ammonia
The deviation curve for ammonia shown in Figure 29 is constructed
from the data of Cragoe, Meyer s , and Taylor (25) and Beattie and Lawrence
(8). The data of Cragoe a r e in excellent agreement with those of Beattie up
to 40 °C. At 70 "C. , which is the highest t empera tu re measured by Cragoe,
his resu l t s a r e about 0.03 a tm. lower than those of Beat t ie . The resu l t s of
Keyes and Brownlee (60) a r e also shown in Figure 29. Keyes and Brownlee 's
resu l t s at low t empera tu res a r e about 0.10 a tm. higher than those of Beattie
and Lawrence , while converging with those of Beattie at higher t e m p e r a t u r e s .
Above llO^C. , however, Keyes ' values drop considerably below those of
Beat t ie . Section III. F d i scusses the considerat ions involved in further detai l .
Our deviation curve agrees with Beat t ie ' s data to within 0.001 a tm. , except
at high t e m p e r a t u r e s , where Beattie did not r epor t his p r e s s u r e s to the third
decimal place. Kopper 's (64) value of 132.5 "C. for the cr i t ica l t empera tu re
was used, and the cr i t ica l p r e s s u r e corresponding to this t empera tu re is
112.53 a tm. These cr i t ica l constants a r e much more consistent with Beat t ie ' s
v a p o r - p r e s s u r e data than those given in the l i t e ra tu re by other authori t ies
whose cr i t ica l p r e s s u r e is about 1 a tm. lower. Arms t rong also a r r ived at the
same conclusion in his unpublished repor t (4) in which a c r i t ica l point of
132.4"'C. and 112.4 a tm. was selected.
(25) Cragoe, C. S. , Meyers , C, H, , and Taylor, C. S. , Natl. Bur . Std.
Sci. and Tech. Pape r s 16, 1 (1920) and J . Am. Chem. Soc. 42, 206 (1920).
(8) Beat t ie , J . A . , and Lawrence , C. K., J . Am. Chem. Soc. 52, 6 (1930).
(60) Keyes, F . G. , and Brownlee, R. B. , J . Am. Chem. Soc. 40, 25 (1918).
(64) Kopper, H. , Z. Physik. Chem. ATTS; 469 (1936).
(4) Arms t rong , G. T. , Natl. Bur. Std. Rept. 2626 (1953).
0.6
0.5
0.4
0.3
0.2
0.1
? 0. • • -
3 -0.1
•° -0.2
-0.3
-0 .4
—
—
—
—
—
—
—
—
—
-33.351 1
-20
1
NH
^•"" - -^^
1
1
3
• ^
1 0
1
• Cragoe
• Keyes
A Bea t t i e
• ^ * ^ A ^
•
1 1 1
•
1 20 40
Temp rc) 1 1 1
• •
1 1 60
1
X
1
J
; /
/
/ r
1 80
1
)
/ I 1 / 1
1 1 100
1
• _
'̂ V V V \
\ A
—
—
1 132.50
o 00 I
0 GLL-637-1721
20 40 6 0 80 100 % 1 / T
Fig . 29. Deviation curve for NH3.
104-
T A B L E XXVIII
VAPOR P R E S S U R E OK NH3
log P^ = - 1 2 0 3 . 0 5 / T + 5 .01689
Pj^, a t m . Pj< ,̂ atmi. d, a t i n .
1.000 1.000 .0
1.070 1.067 - 0 . 0 0 3
1.180 1.172 .008
1.301 1.287 .014
1.430 1.410 .020
1.569 1.543 .026
1.717 1,685 .032
1.878 1.839 .039
2 .050 2 .004 .046
2 .234 2 .180 .054
2 .432 2 .369 .063
2 .643 2 .571 .072
2 .869 2 .787 .082
3 .110 3 .017 .093
3 .367 3 .263 .104
3.640 3 .524 .116
3.930 3.802 .128
4 . 2 3 8 4 . 0 9 8 .140
4 . 5 6 3 4 . 4 1 1 .152
4 . 9 0 8 4 . 7 4 4 .164
5 .273 5.096 .177
5 .659 5 .468 .191
6 .068 5 .862 .206
6 .499 6 .279 .220
6.952 6 .718 .234
7 .429 7 .182 .247
7 .931 7 .670 .261
8 .459 8 .185 .274
9 .013 8 .726 .287
9 .594 9 .295 .299
10.204 9 .893 .311
10.842 10.520 .322
11.512 11 .179 .333
12.213 11.869 .344
12 .945 12.591 .354
13.711 13.348 .363
14.510 14.139 .371
15.344 14.966 .378
16 .215 15.831 .384
17.122 16.733 .389
18.066 17.674 .392
19.052 18.656 .396
2 0 . 0 7 5 19.679 .396 2 1 . 1 3 7 2 0 . 7 4 5 .392
2 2 . 2 4 1 21 .854 .387
2 3 . 3 8 9 2 3 . 0 0 8 .381
- 1 0 5 -
T A B L E XXVIII (Cont inued)
t,> ° c .
S8
60
62 64
66
68
70
72
74
76
78
80
82
84
86
88
. ̂ ° 92
94
96
98
100
102
104
106
108
110
112
114
116
118
120
122
124
125
126
127
128
129
130
131
132
132.50
P J I a t m .
24.580
25.817
27.100
28.430
29.809
31.236
32.714
34.244
35.826
37.459
39.148
40.894
42.699
44.563
46.488
48.474
50.523
52.637
54.819
57.070
59.390
61.780
64 .241
66.776
69.385
72.070
74.830
77.676
80.612
83.643
86.762
89.978
93.293
96.705
98.450
100.221
102.020
103.848
105.715
107.622
109.567
111.535
112.526
Pj.^) a t m .
24.207 25.454
26.749 28.093
29.488
30.934
32.433
33.986
J5.595
37.259
38.982
40.763
42.604
44 .506
46.470
48 .498
50.591
52.749
54.975
57.269
59.632
62.066
64 .571
67.150
69.802
72.530
75.335
78.217
81.178
84.219
87.340
90.544
93.832
97.203
98 .921
100.661
102.422
104.205
106.009
107.836
109.685
111.557
112.501
d 1 a t m
-0 .373
.363
.351
.337
.321
.302
.281
.258
.231
.200
.166
.131
.095
.057
- 0 . 0 1 8
+0.024
.068
.112
.156
.. .199
.242
.286
-'.3 30
.374
.417
.460
.505
.541
.566
.576
.578
.566
.539
.498
.471
.440
.402
.357
.294
.214
.118
+0.022
- 0 . 0 2 5
-106-
21. Cyanogen
Measurements of vapor p r e s s u r e of C2N2 have been repor ted by P e r r y
and Bardwell (92) and by Terwen (109). The resu l t s of both invest igators a r e
in good agreement , and our curve shown in F igure 30 indicates a good fit in
the jhkc region. Terwen 's value of the cr i t ica l t empera tu re I26.55°C. does
not fit well with the deviation curve and Cardoso and Baume's (16) value of
I28.3"'C. is p re fe r r ed . The corresponding cr i t ica l p r e s s u r e is 59.98 a tm.
compared to 58.20 a tm. and 59.75 a tm. reported by Terwen and Cardoso and
Baume, respect ively . Ruehrwein and Giauque's (99) value of the boiling point
is in good agreement with the deviation curve .
(92) P e r r y , J . H. , and Bardwell , D. C. , J .Am. Chem. Soc. 47, 2629 (1925).
(109) Terwen, J , W. , Z. Physik. Chem. 91, 469 (1916).
(16) Cardoso , E. , and Baume, G. , J . Chim. Phys . 10, 509(1912).
(99) Ruehrwein, R. A. , and Giauque, W. F . , J . Am. Chem. Soc. 61,
2940 (1939).
0.5
0.4
0.3
0.2
0.1
0
-0
C2N2
-21.15
GLL-637-1722
A Per ry
• Te rwen
j _ j _
20 40 60 Temp (°C)
I I \
80 J L
100 128.30
o I
20 40 60 % l / T
80 100
Fig . 30. Deviation curve for C^N-.
- 108-
T A B L E XXIX
V A P O R P R E S S U R E O F C2N
log P = - 1 2 0 3 . 5 7 / T + 4 .77607
t, 'C.
21.15
20
18
16 14
12
10
8
6
4 -2
0
+ 2
4 6
8 10 12
14
16 18
20 22 24 26 28 30
32
34
36 38 40 42
44
46 48 50 52
P p a t m .
1.000
1.052
1.151
1.258
1.373
1.494
: .6Z4
1.763
1.911
2.066 2,234
2.413
2.603
2.803 3.014
3,237 3.473 3.723
3.986 4 .263
4.554
4.860 5.182 5.518 5.872 6.244 6.631
7.038
7.463
7.906 8.370 8.853 9.358
9.883 10.432
11.002 11.595 12.211
P j^ , a t m .
1.000
1.051
1.145
1.246 1.354
1.470
1.594
1.725
1.866
2.015 2.174
2.343
2.523
2.713 2.914
3.127 3.353 3 .591
3.843 4 .108
4 .388
4 .682 4 .992 5.317 5.659 6.019 6.395
6.790
7.204
7,637 8.090 8,563 9,058
9.574 10.113
10.675 11.261 11.871
d, a t m
.0
- 0 . 0 0 1
.006
.012
.019
.024
.020
.038
.045
.051
.060
.070
.080
.090
.100
.110
.120
. L 1 ^
143 155
. loo
.178 19c 20 i
.215
.225
.236
.248
.259
.269
.280
.290
.300
.309
.319
.327
.334
.340
- 109-
TABLE XXIX (Continued) P - , a t m .
1 2 . 8 5 2
1 3 . 5 1 8 1 4 . 2 1 0 1 4 . 9 2 8
15 .674
1 6 . 4 4 7
1 7 . 2 4 7
1 8 . 0 7 6
1 8 . 9 3 2 1 9 . 8 2 0
2 0 . 7 3 4
2 1 . 6 7 9
2 2 . 6 5 3 2 3 . 6 5 8
2 4 . 6 9 3
2 5 . 7 6 1
2 6 . 8 6 0
2 7 . 9 9 3
2 9 . 1 6 1 3 0 . 3 6 8
3 1 . 6 0 6
3 2 . 8 8 0
3 4 . 1 8 9
3 5 . 5 3 6
3 6 . 9 2
3 8 . 3 5
3 9 . 8 2
4 1 . 3 3
4 2 . 8 8
4 4 . 4 8
4 6 . 1 3
4 7 . 8 3
4 9 . 5 9 5 1 . 4 2
5 3 . 3 3
5 5 . 3 3
5 6 . 3 6
5 7 . 4 3
5 8 . 5 2
5 9 . 6 4
5 9 . 9 8
P j ^ , a t m . d ,
1 2 . 5 0 6 - 0
1 3 . 1 6 6 1 3 . 8 5 3 1 4 . 5 6 7
1 5 . 3 0 8
1 6 . 0 7 8
1 6 . 8 7 7
1 7 . 7 0 5
. 1 8 . 5 6 3 1 9 . 4 5 3
2 0 . 3 7 4
2 1.327
2 2 . 3 1 3 2 3 . 3 3 3
2 4 . 3 8 7
2 5 . 4 7 7
2 6 . 6 0 2
2 7 . 7 6 3
2 8 , 9 6 1 3 0 . 1 9 8 3 1 . 4 7 2
3 2 . 7 8 6
3 4 . 1 3 9
3 5 . 5 3 3 - 0 .
3 6 . 9 6 9 , - 0
3 8 . 4 4 6 3 9 . 9 6 5
4 1 . 5 2 8
4 5 . 1 3 4
4 4 . 7 8 5
4 6 . 4 8 1
4 8 . 2 2 3
5 0 . 0 1 1
5 1 . 8 4 6 5 3 . 7 3 0
5 5 . 6 6 1
5 6 . 6 4 5
5 7 . 6 4 2
5 8 . 6 5 1
5 9 . 6 7 2
5 9 . 9 8 1
atnr
. 3 4 6
, 3 ^ 2 . 3 5 7
^361
. 3 6 6
. 3 6 9
. 370
. 3 7 1
. 3 6 9
. 3 6 7
. 3 6 0
. 3 5 2
. 3 4 0
. 3 2 5
306
2 8 4
2 58
230 2 CO
I 70
134
0 94
0 50
oo:-0 4 o
0 99 •50
20>
2 54
2 04
J 52
3 92
4 2 0
4 2 6
2 9 6 3 30
2 8 1
2 1 6
132
0 3 3
0 0 1
-110-
22. Sulfur Dioxide
Although a grea t many m e a s u r e m e n t s of the vapor p r e s s u r e of SO-,
have been made, the data a r e in poor agreement above 30 "C. Between the
boiling point and 30°C. , Hirth, as quoted in reference (57) (which contains
data obtained independently by Hirth, Kang, and Hellwig) and Riedel (98) a r e
in excellent agreement . Riedel 's boiling point value of - lO .Ol 'C . has been
used by us . Between 30 and 95 °C. Hir th ' s and Kang's data quoted in r e f e r
ence (57) a r e in radical d i sagreement with each other . Unfortunately their
paper does not resolve this question, and no other data of comparable p r e
cision a r e available for confirmation of the t rue p r e s s u r e s . Toriumi and
Hara ' s (HO) measu remen t s shown in F igure 31 general ly support Hir th ' s r e
su l t s . The data of Regnault (96) and Cardoso and Fiorentino (17) not shown
in F igure 31, a r e quite sca t te red in this region. This mean of Regnault 's
data appears to support Hirth, while the data of Cardoso and Fiorent ino a r e
c lose r to those of Kang and Hellwig quoted in reference (57). Pending defini
tive m e a s u r e m e n t s , we have chosen Hir th ' s data for the location of the devi
ation curve in the 30-95"'C. range, since his measu remen t s a r e in good a g r e e
ment with p rec i se measu remen t s above and below these t e m p e r a t u r e s , and a
deviation curve through his data harmonizes best with other curves in F igure
3. F r o m 95 to 135°C. Kang's points have been used to locate the deviation
curve . F rom 135 °C. to the cr i t ica l point Kang's data a r e inconsistent and
indicate an inflection point in the kc region which is considered to be spur ious .
Our deviation curve has been drawn in the kc region to harmonize with Kang's
data in the jh region and with other deviation curves in Figure 3.
- 1 1 1 -
(57) Kang, T. L. , Hir th, L. J . , Kobe, K. A . , and McKetta, J . J . , J . Chem.
Eng. Data 6, 220 (1961).
(98) Riedel, L. , Bull. Intern, Inst, Refrig, 20, No. 4, Annex No. 5, Bl
(1939).
(110) Tor iumi , T. , and Hara , R. , J . Soc. Chem. Ind. (Japan) 47, 502 (1944).
(96) Regnault, H, V. , Mem. De P a r i s 26, (1862).
(17) Cardoso, E. , and Fiorent ino, U. , J . Chim. Phys . 23, 841 (1926).
T3
0 10
GLL-637-1723
100
I
F i g . 3 1 . D e v i a t i o n c u r v e for SO2-
-113-
TABLE XXX
VAPOR PRESSURE OF SO2
log P „ = -1279 .15 /T + 4.86128
t , • € .
10 .01
10 .00
8
6
4
- 2
0
+ 2
4
6
8
10
12
14
16
18
20
22
24
26
2 8
30
32
34
36
38
40
42
44
4 6
4 8
50
52
54
56
58
60
62
64
66
68
70
72
P . , a t m . 1
1.000
1.001
1.092
1.190
1.296
1.410
1.532
1.661
1.799
1.946
2.102
2.267
2.444
2.631
2.828
3.037
3.258
3.492
3.738
3.997
4.269
4.557
4.858
5.174
5.507
5.854
6.219
6.600
6.998
7.415
7.851
8.305
8.780
9.272
9.786
10.318
10.873
11.447
12.045
12.667
13.311
13.980
14.676
1.000
1.001
1.089
1.183
1.284
1.392
1.508
1.631
1.762
1.901
2.049
2.206
2.374
2.551
2.738
2.936
3.146
3.368
3.602
3.849
4.108
4.383
4 .671
4.974
5.293
5.626
5.977
6.345
6.730
7.133
7.555
7.996
8.458
8.939
9.442
9.966
10.513
11.082
11.675
12.293
12.935
13.602
14.296
.0
.0
-0 .003
.007
.012
.018
.024
.030
.037
.045
.053
.061
.070
.080
.090
.101
.112
.124
.136
.148
.161
.174
.187
.200
.2 14
.228
.242
.255
.268
.282
.296
.309
.322
.333
.344
.352
.360
.365
.370
.374
.376
.378
.380
- 1 1 4 -
T A B L E XXX (Cont inued)
i> -c 74
76 78 80 82 84 86 88 90 92 94 96
98 100 102 104 106
108
110
112
114
116
118 120
122 124 126 128
130 132 134 136 138
140
142 144 146
148
150
151
152
154 156 157 157.50
P|) atm,
15.397
16.145 16.920
17.725 18.556 19.417 20.308
21.228 22.178 23.160 24.172 25.217
26.293 27.405 28.544
29.729 30.949
32.206
33.502
34.838
• 36.215
37.633
39.095 40.598
42.144 43.734 45.366
47.043
48.765 50.533 52.356 54.227 56.151
58.126
60.154 62.236 64.374
66.569 68.822
69.968
71.132
73.504 75.939 77.181 77.810
Pl<Jy atlDi
15.016
15.764 16.540
17.345
18.179 19.043 19.938
20.864
2̂ 1.822
22.814
23.839
24.898
25.991 27.121 28.282
29.489 30.729
32.008
33.325
34.682
36.080
37.518
38.999 40.522
42.088
43.698
45.352
47.051
48.797 50.589 52.428 54.315 56.251
58.236
60.270
62.356
64.492
66.681
68.922
70.062
71.216
73.564
75.966
77.188
77.804
d. fttn
-0.381
.381
.380
.380
.377
.3 74
.370
.364
.356
.346
.333
.319
.302
.284
.262
.240
.220
.198
.177
.156
.135
.115
.096
.076
.056
.036
-0.014
+0.008
.032
.056
.072
.088
.100
.110
.116
.120
.118
.112
.100
.094
.084
.060
.027
+0.007
-0.006
-115-
23, Hydrogen Fluor ide
The data of J a r r y and Davis (55) and Franck and Spalthoff (29) a r e in
good agreement and appear to have good prec i s ion . F ranck and Spalthoff
a r e to be commended for the care taken in adequately defining the kc region
of the curve . We note, however, in comparing in F igure 4 the deviation
curve for HF with that obtained for N^O ., that the HF curve lies somewhat
to the right of the N2O . curve in the kc region. In drawing the N^O , curve ,
we have p re fe r red the data of Schlinger and Sage over that of Sheffer and
Treub, whose points seem to exhibit a typical l o w - p r e s s u r e defect in this
region. It is poss ible , then, that F ranck and Spalthoff s data may be slightly
low in this region a l so . Kelley's (59) boiling point of 19,5 "C. appears to
ag ree with the above data .
(55) J a r r y , R. L. , and Davis, W. , J r . , J . Phys . Chem, 57, 600 (1953)
and Am. Doc. 4069.
(29) F ranck , E . V . , and Spalthoff, W. , Z . E lek t rochem. 6j., 348 (1957).
(59) Kelley, K. K. , U. S. Bur. Mines Bull, 383 (1935),
6
GLL-637-1725 % l / T
F ig . 32. Deviation curve for HF,
100
I
- 1 1 7 -
T A B L E XXXI
V A P O R P R E S S U R E O F H F
log P j , = - 1 4 4 6 , 9 7 / T + 4 .94437
t , " C .
19 .5
20
25
30
35
40
4 5
50
55 60
65
70
75 80 85
90 95
100
105
110
115
120
125
130
135
140 145
150
155
160
165
170
172
174
176
178
ISO
182
184
186 188 .0
p., a t m .
i.OOO
J . 0 1 8
1,208
1.433
1.097
1.998
2 . 2 6 6 2 . 7 2 9
3 . 1 9 9 2 . 6 7 2
4 . 2 3 7
4 . 8 6 1 5 .540
6 . 2 9 9 7 . 1 5 8 8 ,12
9 . 1 9
1 0 . 3 6
1 1 . 6 8
1 3 . 0 7
14 .64
1 6 . 3 8
1 8 . 3 1
2 0 . 4 3
2 2 . 7 2
2 5 . 2 3
2 7 . 9 5
3 0 . 8 8
3 4 . 0 7
3 7 . 5 0
4 1 . 2 2
4 5 . 2 3
4 7 . 1 0
4 8 , 9 9 5 0 . 9 2
5 2 . 9 2
5 4 . 9 7
5 7 . 1 0
5 9 , 3 2
6 1 , 6 4
6 4 , 0 6
P T ^ , a t m i .
1.000
1.020
1.234
1.483
1.773
2 . 107
. 2 . 4 9 0
2 , 9 2 9
3 . 4 2 7
3 . 9 9 1 1.627
5 . 3 4 1 6 . 1 4 0
7 . 0 3 1 8 . 0 2 1
9 .12
1 0 . 3 3
1 1 . 6 6
13 .12
1 4 . 7 2
1 6 . 4 6
1 8 . 5 6
2 0 . 4 2
2 2 . 6 6
2 5 . 0 7 2 7 . 6 7
3 0 . 4 8
3 3 . 4 8
3 6 . 7 1
4 0 . 1 6
4 3 . 8 4
4 7 . 7 2
4 9 . 4 1
5 1 . 1 0
5 2 . 8 2
5 4 . 5 8
5 6 . 3 9 5 8 . 2 4
6 0 . 1 4
6 2 , 0 8
6 4 , 0 6
d , a t m
0
. 002
. 0 2 6
. 0 5 0
. 0 7 6
. 1 0 9
. 1 2 4
.2 00
. 2 2 8
.3 19
. 3 9 0
. 480
. 6 0 0
. 7 3 2
. 8 6 3 1.00
i 14
1.30
1.44
1 D l
1.81
L9tf
2 . 1 .
2 . 2 3 2 . 3 5
2 . 4 4
2 . 5 2 2 , 6 0
2 o4
^ , 6 6
2 . 6 2
2 . 4 9
2 .3x
2 . 1 i
1.90
1,66
1,42
1.14
, 8 2
. 4 4
.0
-118-
24. Hydrogen Cyanide
Giauque and Ruhrwein 's (38) boiling point is in good agreement with the
p r e s s u r e measu remen t s of Hara and Sinozaki (46) and Bredig and Teichman
(14). Above 50 "C. the data of Bredig and Teichman shown in F igure 33 a r e
s p a r s e but show a reasonably accura te fit to a curve based on our N-,0_>
curve . Bredig and Teichman's cr i t ica l p r e s s u r e (53.2 atm.) is in very poor
agreement with their c r i t ica l t empe ra tu r e and we have selected a c r i t i ca l
p r e s s u r e of 48.89 a tm.
(38) Giauque, W. F . , and Ruhrwein, R. A. > J. Am. Chem. Soc. 6J, 2626
(1939).
(46) Hara, R. , and Sinozaki, H. , Tech. Repts . Tohoku Imp. Univ. 4, 145
(1924).
(14) Bredig, G. , and Teichman, L. , Z. Elekt rochem. M, 449 (1925).
1.2
1.0
0 .8
0 .6
0 .4
0 ,2
rii
—
—
-
-
-
2 5 . 7 |
HON
1 40
1 1
i 1 60
1
AHara
• B r e d i g
1
1
• >*
^y^ " ^
1 1 1 80 100 T e m p ( ° C )
1 1
y ^
1
/
^ •
1 1 120
1
^
1 140
1
- < A
1 1 160
1
\
\
\
\
\
1 1 183.5
0 10 GLL-637-1726
20 30 W 40 50 % l / T
F i g . 33 . Dev ia t ion c u r v e for HON.
70 80
I
90 100
- 1 2 0 -
T A B L E XXXII
V A P O R P R E S S U R E O F HCN
log P j , = - 1 4 5 9 . 4 2 / T + 4 .88345
t, "C.
25.7
30
35
40
4 5
50
55
60
65
70
75 80
85
90
95
100
105
110 115
120
125
130
135
140
145
150
155
160
165
170
174
176
177
178
179
180
181
182
183
183.5
p . , a t m .
1.000
1.17
1.40 1.66
1.97 2.31
2.70 3.13
3.61
4.14 4.72 5.36
6.08
6.89
7.79 8.78
9.89 11. t l 12.45
13.92 15.53
17.29 19.21 21.29
23 .55 26.01
28.66 31.54 34.65
38.02
40 .95
42 .51 43 .32 44 .14
44 .98
45 .82
46 .69 47.50 48 .45
48 .89
P j^ , a t m .
1.000
1.17
1.40 1.67
1.98 2.33
2.73 3.18
3.69
4 .27 4 .92 5.63
6.43 7.32
8.30 9.38
10.57 11.87 13.29
14.84 16.51
18.34 20 .31 22.44
24 .73 27.20
29.84 32.67 35.69
38.92
41 .65
43 .07 43 .79 44 .52
45 .26
46.00 46 .76
47 .53 48 .31
48.70
d, a tm .
-0
.0
.0
. 0 1
. 0 1
. 0 2
. 0 3
. 0 5
. 0 8
. 1 3
. 2 0
. 2 7
. 3 5
. 4 3
. 5 1
.bO
. 6 8
. 7 b
. 84
,9c
98
!.0 5 1. [V
1. i5
1 18 1.19
i , i 8 1.13 1 04
. 90
. 70
. 5 6
.47 •
.38 •
. 2 8
. 1 8
. 0 7
+ 0.03 - 0 . 1 4
- 0 . 1 9
- 1 2 1 -
25. Nitrogen Tetroxide
V a p o r - p r e s s u r e measu remen t s have been made by Baume and Robert
(7) up to 38' 'C. and 2 a tm. ; by Mit tasch, Kuss , and Schlueter (80) up to 60°C.
and 5 a tm.; by Schlinger and Sage (105) up to 149 "C. and 79 atm.; and by
Scheffer and Tr&ub (103) up to the cr i t ica l t empera tu re of 158.2''C. Bennewitz
and Windisch (10) repor t a cr i t ica l t empera tu re value of 158.4''C. The c r i t i
cal p r e s s u r e of N^O . has never been experimental ly de te rmined .
Cr i t ica l values of 158.0 "C. and 99 a tm. , which a r e at t r ibuted by Kobe
and Lynn (63) to Baume and Robert , appear in real i ty to be due to Cragoe ' s
calculated values given in the International Cri t ical Tables (54). The resu l t s
of all invest igators a r e in good agreement up to 130 °C. , as shown in F igure
34. Above this t empera tu re some of Sheffer and Treub ' s data exhibit a low-
p r e s s u r e "nose, " and since Schlinger and Sage's data show the mos t cons is t
ent prec is ion , we have chosen to extrapolate their data to the observed c r i t i
cal t empera tu re where we find fair agreement with Sheffer and Treub. The
c r i t i ca l p r e s s u r e determined by the deviation curve is 99.66 a tm . Kelley's
(59) boiling point of 21.0*0. appears to ag ree well with these data.
(7) Baume, G. , and Robert , M. , Compt. Rend. 168, 1199 (1919).
(80) Mit tasch, A., Kuss, E . , and Schlueter , H. , Z. Anorg. AUgem. Chem.
^ , 1 (1926).
(105) Schlinger, W. G. , and Sage, B. H., Ind. Eng. Chem. 42, 2158 (1950).
(103) Schef fe r ,F . E. C , and Treub, J . P . . Z. Physik. Chem. 8^, 308(1913).
(10) Bennewitz, K. , and Windisch, J . J . , Z. Physik. Chem. A166, 401 (1933).
(63) Kobe, K. A . , and Lynn, R. E. , J r . , Chem. Rev. 52, 117 (1953).
(54) "International Cri t ical T a b l e s , " Vol. Ill, McGraw-Hil l Book Company,
I n c . , New York, 1928, pp. 201-249.
(59) Kelley, K. K. , U. S. Bur . Mines Bull. 383 (1935).
2.
2 . 4 -
2.0
N2O4
21.0
0 10 GLL-637-1727
40
• Sch l inge r
•She f fe r
^ M i t t a s c h
I 60 80
T e m p (°cO 100
J u 120
± ± 20 30 40 50
% 1/T
60 70 80
± 140 158.2
90 100
tSJ
I
F i g . 34. D e v i a t i o n c u r v e for N ^ O ^ .
- 1 2 3 -
T A B L E XXXIII
VAPOR P R E S S U R E O F N^O^
t , ° C .
21
22
24
26
28
30
32
54
:-6
38
40
4 2
4 4
4 6
4 8
50
52
54
56
58
60
62 64
66
6 8
70
72
74
76
78
80
82
84
8b
8 8
90
92
l og P^ =
P j , a t m .
1 .000
1.046
! . 1 4 4
1.251
1.368
1.494
; . 6 3 0
i . 7 7 o
1.954
2 . 1 0 6
2 . 2 9 0
2 . 4 8 9
2 . 7 0 4
2 . 9 3 3
3 . 1 7 9
3 . 4 4 4
3 . 7 2 7
4 . 0 2 7
4 . 3 4 7
4 . 6 8 9
5 . 0 5 4
5 . 4 4 3 5 . 8 5 8
6 . 3 0 0
6 . 7 7 2
7 . 2 7 4
7 . 8 1 0
8 . 3 7 8
8 . 9 8 2
9 . 6 2 2
1 0 . 2 9 9
1 1 . 0 2 0
1 1 . 7 8 2
1 2 . 5 9 3
i 3 ; 4 4 8
1 4 . 3 5 6
1 5 . 3 1 4
- 1 8 4 8 . 2 0 / T + 6 . 2 8 3 2 0
P j ^ , a t m .
1.000
1.050
1.157
1.274
1.400
1 . 5 3 D
^ . . 6 8 5
1 .845
2 . 0 1 8
2 . 2 0 4
2 . 4 0 6
2 . 6 2 2
2 . 8 5 5
3 . 1 0 6
3 . 3 7 5
3 . 6 6 3
3 . 9 7 2
4 . 5 0 3 4 . 6 5 7
5 . 0 3 6
5 . 4 3 9 5 . 8 7 0
6 . 3 2 9
6 . 8 1 8
7 . 3 3 9 7 . 8 9 2
8 , 4 8 1
9 . 1 0 5
9 . 7 6 7
1 0 . 4 6 9
1 1 . 2 1 3
1 2 . 0 0 0
1 2 . 8 3 3
1 3 . 7 1 4
1 4 . 6 4 4
1 5 . 6 2 6
1 6 . 6 6 2
d , a t m .
. 0 0 0
004
0 1 3
0 23
, 032
0 4 2
0 5 5
. 0 6 9
. 0 8 4
. 0 9 8
. 1 1 6
. 1 3 3
. 1 5 1
. 1 7 3
t9D
. 2 . 9
24 5
2 7-j
3 .0
.34 7
3^^5 42 7
^ 4 7 1
, 5 ' 8
^o7
D S
, b 7 ;
7-7
.7>?5
. 8 4 7
-914
. 9 8 0
1.051
l . i 2 1
1.19b
1.270
1 3 4 8
- 1 2 4 -
TABLE XXXIII (Continued)
t, °c . 94
96
98
100
102
104
106
108
110 112
114
116
118
120
122
124
126
128
130
132
134
136 138
140
142
144
146
148
150
151
152
153
154
155
156
157
158 158.2
P . , a t m .
16.328
17.402
18.533
19.728
20.988
22.317
23.714
25.185 2 6 . 7 4 1 28.382
30.111
31.933
33.846
35.856 37.961
40 .169
42 .491
44 .941 47 .511 50.21 53.05 56.02 59.14
62.41 65.83
6 9 . 4 i 73.16 77.08
81.16
83.27 85.41
87.60 89.83
92.10
94.42 96.78 99.18 99.66
P j^ , a t m .
17.754
18.904
20.116
21 .391 22.732
24 .141
25.b22
27.176 ^ 28 .807
30 .518
32.310
34 .188
36 .154
38.212 40 .364
42 .613
44 .964
47 .418 49 .981 52.654 55.442 58 .348 61,377
64.530
67.813
71.229 74.783 78.476
82 .316
84 .291 86 .303
88 .356 90.445
92.574
94.743 96.952 99.203 99 .658
d, a t m .
1.426
1.502
1.583
1.663
1.744
1 824
1.908
1.991 2.066 2.136
2 .199 2 .255
2 .308
2.356 2.403
2.444
2.4 73
2 477 2,470 2 443 2 3 9: 2,3 24 2 239
2. 124 i .987
1.822 L b 2 l 1.400
1.158
1.025
.891
.757
.615
.4b9
.324
.176 + 0.027 - 0 . 0 0 2
-125-
26. Bromine
The only h igh -p re s su re measu remen t s on bromine have been made by
Scheffer and Voogd (104). Their resu l t s a r e in ag reement with our deviation
curve shown in F igure 35; however, no data were taken above 200 "C. Be
yond this point, the curve is projected so as to correspond with other curves
shown in F igure 4. Scheffer and Voogd did de te rmine the cr i t ica l t empe ra
ture to be 3 11 °C. and calculated a corresponding cr i t ica l p r e s s u r e of 102 a tm.
This value is in good agreement with our deviation curve and is definitely to
be p re fe r red over StuU's value of 121 a tm. (108) calculated from Nadejine's
(82) c r i t ica l t empera tu re of 302 °C. StuU's boiling point (108) has been used.
(104) Scheffer, F . E . C , and Voogd, M., Rec. T rav . Chim. 45, 214 (1926).
(108) Stull, D. R. , Ind. Eng. Chem. 39, 517 1684 (1947).
(82) Nadejine, Bull. Acad. Imp. Sci. St. Pe t e r sbu rg 30, 327 (1886).
d(a
tm)
era
O
3 n c <
0)
i-h 0 td
tv
P I ON
O
J -<
1 I H
-J
ro
CO
>
ro
O
OJ O 8-
^ C
Ji
:- o
en o el-
cx>
o to
o
o
o
I I
I p
po
o
pp
op
oo
pp
OJ
ro
—
o
—
ro
OJ
i^
b
i en
->
i bo
CO
CJ
I
P
ro
GO
O o
o
-• m
h
s "0 go
h
-• c ^ m
""^
L
0 r
^0
0 •^
o
[—
ro
ro
O
ro
o>
o —1
—1 1
1
- _ •
•
~ •
—
—
1 f
1 1
1 1
1 1
1 1
1 r I OD
1 i^
" m
( 1 1 1 J *
1 1 1 *
1 *
/ [ Y N
. •
• ^
s^
• •
^v
^^
^\
^ ^
S^ \
^^
.^
1
•92
1
127-
t, °C. P . , a t m . P , atnn. d, a t m .
1 r\
58.2 1.00 1.000 .0
60 1.06 1.059 -0 .002
70 1.45 1.444 .012
80 1.96 1.934 .022
90 2.58 2.549 .034
100 3.36 3.311 .049
110 4.30 4 .241 .062
120 5.44 5.365 .080
130 6.81 6.708 .102
140 8.42 8.297 .120
150 10.30 10.160 .135
160 12.47 12.326 .145
170 15.97 14.823 .150
180 17.83 17.682 .145
190 21.06 20 .931 .125
200 24 .67 24.602 - 0 . 0 7 0
210 28.72 28 .724 .000
220 33.22 33.32 +0.10
230 38.22 38.44 .22
240 43.75 44 .09 .34
250 49 .87 50.31 .44
260 56.61 57.12 .51
270 63.98 64.54 .56
280 72.04 72.62 .58
290 80.80 81.36 .56
300 90.38 90.80 .42
305 95.50 95.79 .29
311.0 102.00 102.00 .00
-128-
27. Sulfur Trioxide
The deviation curve for SO^ was calculated from original data kindly
supplied by Dr . P . F . Tiley (1). We have computed a boiling point of 44.55*0.
from our deviation curve . Hyne and Tiley (53) have repor ted a boiling point
of 44.45 ± 0,15*C. Tiley (1) has determined the cr i t ica l point to be 217.7*0
± 0.2 *C. and calculated the cr i t ica l p r e s s u r e to be 80.8 a tm. We have ca l
culated a P of 81.44 a tm. from our deviation curve , est imating a kc peak
height equivalent to that for SO^ in absence of p rec i se data in this region.
The resu l t s of Smits and Schoenmaker (107) and Berthoud (11) a r e in good
agreement at the boiling point and Berthoud's data a r e in fair agreement near
the c r i t i ca l point. Berthoud's c r i t i ca l point is 218.2*0. and 83.8 a tm.
(I) Abercomby, D. C , and Tiley, P . F . , J . Chem. Soc. (London) lg.63, 4902.
(53) Hyne, R. A . , Tiley, P . F . , J . Chem. Soc. (London) 1961, 2348.
(107) Smits , A . , and Schoenmaker, P . , J . Chem. Soc. (London) 19^26, 1108.
(II) Berthoud, A. , Helv. Chim. Acta 5̂ , 513 (1922).
GLL-637-1729
40 60 7o( l / T )
100
tv sO I
Fig . 36. Deviation curve for SO3.
- I S O -
T A B L E XXXV
VAPOR P R E S S U R E O F SO3
1 6 2 3 . 8 7 / T + 5.22851
t, °C. 44 ,55
4 5
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
130
135
140
145
150
155
160
165
170 175
180 185
190 195 200
205
210 212
214 216
217 217.7
log
Pi" 1
1
1
1 •>
2
2
3 4
5
5
6
7
9
10
11
13
14,
16,
^ ^ K ^ a t m .
. 00
.02
.30
. 6 3
. 0 1
, 46
. 9 8
. 5 8
. 26
. 04
.90
. 8 6
. 9 1
. 0 7
. 3 3
.72
.22
.86
,67
18.61 20.
22 ,
2 5 .
2 7 .
3 0 .
3 3 .
3 6 .
4 0 .
4 3 .
4 7 .
5 2 .
56 .
6 1 .
6 6 .
7 1 .
7 4 .
7 6 .
7 9 .
8 0 .
8 1 .
,70
.91
.29
84
,62
61
83
29
97
90
10
58
35
44
89 22
64
18
50
4 4
K' 1 1
1
1
2
2
3
3 4
4
5
6
7
8
9 11
12,
14,
15.
17,
19.
2 2 ,
a t m . .31 . 33
.60
. 9 1
. 26
,b7
. 14
. 6 7
,27
. 9 5
. 7 1
. 5 7
. 53
.60
. 78
. 0 9
.53
.12
,87
.78
,86
,13
24.60
2 7 .
3 0 .
3 3 .
3 6 .
4 0 .
4 4 .
4 8 .
5 2 .
5 7 .
6 2 .
,27
,17
29 65
27
16 32
77 52
58
67.98
7 3 .
7 6 .
7 8 .
8 1 .
8 2 .
8 3 .
7 1
10
54
04
32
22
d , + 0
-fO
- 0
- 0
+ 0
a t m .31
.31
.30
28
25
21
. l b
.09
.01
.09
.19
.29
.38
.47
.55
.63
,b9
74
,80
83
84
.78
o9
57 .45
,18
. 0 ^
.19 ,42
.67
.94
,23
.54
,82
,88
.90
,86
,82
,78
- 1 3 1 -
28. Carbon Tet rachlor ide
The data of Young (119) and Wer the imer (115) shown in F igure 37 a r e
in good agreement and give a well defined deviation curve . Young's c r i t i ca l
point value of 283.15*0. and 44.97 a tm. is well confirmed by the deviation
curve . Hildenbrand and McDonald's (48) boiling point of 76.73*0. is used.
(119) Young, 5 . , J . Chem. Soc. 59, 911 (1891).
(115) Wer the imer , E. , Ber . Deut. Physik. Ges . 21, 435 (1919).
(48) Hildenbrand, D. L. , and McDonald, R. A. , J . Phys . Chem. 63, 1521
(1959).
s TJ
0 . 4
0 . 3
0 .2
0.1
0
-0 .1
-0.2
C C l
76.7 100
0 10 GLL-637-1730
•Young
• W e r t h e i m e r
I 120 140 160
T e m p (°C)
180 ± _L
200 240
20 30 40 50 60 % l / T
70 80
260 283.2
90
OJ tv
100
F i g . 37. D e v i a t i o n c u r v e for C C l ^ .
- 133-
T A B L E XXXVI
VAPOR P R E S S U R E O F CCl
log Pj^ = -1558 .62 /T + 4.45472
t, ' C . P . , a tm . 1
76.73 1.00
80 1.10
85 1.28
90 1.47
95 1.68
100 1.92
105 2.19
110 2.48
115 2.80
120 3.15
125 3.53
130 3.94
135 4.40
140 4.89
145 5.42
150 5.99
155 6.61
160 7.27
165 7.98
170 8.74
175 9.54
180 10.39
185 11.30
190 12.27
195 13.30
200 14.40
205 15.56
210 16.79
215 18.09
220 19.46
225 20.91
230 22.44
235 24.07
240 25.78
245 27.59
250 29.49
255 31.49
260 33.59
265 35.81
270 38.14
275 40.59
280 43.15
283.15 44.97
' K ' ^'™-1.000
1.10
1.267
1.455
1.664
1.896
2.153
2.437
2.749
3.092
3.468
3.878
4.325
4.810
5.337
5.907
6.522
7.184
7.897
8.661
9.480
10.356
11.291
12.287
13.348
14.474
15.669
16.934
18.273
19.687
21.179
22.751
24.405
26.143
27.969
29.883
31.888
33.986
36.180
38.470
40.860
43.351
44.974
d, a tm
.0
-0 .003
.009
.015
.021
.027
.033
.040
.047
.054
.060
.066
.072
.077
.082
.085
.087
.086
.084
.076
.060
.038
-0.012
+ 0.017
.047
.077
.110
.145
.182
.223
.268
.306
.336
.362
.380
.393
.400
.393
.368
.330
.270
.202
.0
-134-
29. Tin Tet rachlor ide
Young (119) and Wer th imer (115) have measured the vapor p r e s s u r e of
SnCl . , and their data a r e in agreement on a boiling point of 114.1*C. Above
280*0. Young's data that a r e not shown in F igure 38 a r e evidently inaccura te
and we have used Wer the imer ' s data to the cr i t ica l point. The cr i t ica l -poin t
values of 318.7*0. and 36.95 a tm. a r e repor ted by Wer the imer but appear to
be based on Young's calculated T of 318.7*C. , corresponding to his observed
cr i t ica l p r e s s u r e of 36.95 a tm. (120).
(119) Young, S. , J . Chem. Soc. 59, 911 (1891).
(115) Wer the imer , E. , Ber . Deut. Physik. Ges. 2^, 435 (1919).
(120) Young, S. , Sci. P r o c . Roy. Dublin Soc. 12, 374 (1909).
a 4-"
T3
0 10 GLL-637-1731
100
Fig . 38. Deviation curve for SnCl^.
- 1 3 6 -
T A B L E X X X V I I
V A P O R P R E S S U R E O F S n C l ^
log P = - 1 ? 5 6 . 0 5 / T + 4.53467
t, °c . 1 14.1
lis 120
125
130
135
140
145
150
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
245
250
255
2 60
265
270
275
280
285
2 90
295
300
i05
310
315
318.7
P̂ , atm.
1.00
1.02 1.18
1.35
1.54
1.74
1.97
2.21
2.48
2.78
3.10
3.45
3.83
4.24
4.68
5.16
5.67 6.21
6.80
7.42
8.08
8.79
9.55
10.35
11.20
12.10
13.04
14.05
15.12
16.24
17.42
18.66
19.98
21.37
22.82
24.36
24.97
27.67
29.45
31.32
33.28
35.34
36.95
Pj^, atm.
1.000
1.024 1.170
1.331 1.510
1.707
^ 1.924
2.163
2.425
2.711
3.024
3.364
3.733
4.133
4.565
5.032
5.535
6.076
6.657
7.279
7.945
8.656
9.414
10.222
11.080
11.992
12.959
13.983
15.066
16.209
17.415
18.687
20.026
21.433
22.910
24.461
26.086
27.787
29.567
31.427
33.370
35.396
36.950
d, atmi
.000
-0.001
.008
.017
.025
.033
.042
.050
.060
.069
.079
.089
.100
.109
.118
.126
.133
.138
.140
.141
.140
.138
.134
.126
.1 15
.103
.087
.069
.04 9
.027
-0.003 4 0.0̂ 22
.045
.067
.085
.100
.112
.118
.118
.109
.088
.052
.0
-137-
30. Water
The deviation curve for H^O taken from the tables of Osborne, Stimson,
and Ginnings (86), is presented in Figure 39 for the purpose of comparison
with the other curves in this r epor t . The fact that water is highly associa ted
is responsible for the disproport ionate length of the bj section of the curve .
It should be noted, however, that the sum of the j and k peaks of 1.22 a tm. is
only slightly higher than that of HCl, H^S, HBr, and HI and less than that for
HF, N^O^, and SO^.
(86) Osborne , N. S. , Stimson, H. F . , and Ginnings, D. C. , J . Res . Natl.
Bur . Std. 23, 261 (1939).
1.2
1.0
0.8
0.6
0-4
0.2
S 0 a '^ -0.2
-0.1
—
-
—
-
-
-
-
-
ioo |
H^O
1
I
1 140
1
1
«
J 1 1 180 220
Temp (°C)
1 1 1
1 1 260
1
y V 1 1
300
1
/ ' \
/ \
/
/
1 1 1 34q374;l^
1 0 10
GLL-637-1732
20 30 40 50
% l / T
60 70 80
00 00
90 100
Fig . 39. Deviation curve for H^O.
-139-
IV. ACKNOWLEDGMENTS
We wish to thank Joseph L. Brady and M r s , Mary Lou Higuera of the
Computation Division of the Lawrence Radiation Laboratory (Livermore) for
their help in p rogramming and running the calculations for this work; and
Donald G. Miller of the Chemist ry Depar tment for his helpful c r i t i c i sm .
- 140-
V. REFERENCES
(1) Abercomby, D. C. , and Tiley, P . F . , J . Chem. Soc. (London) 1963,
4902.
(2) Adwentowski, K. , Intern. Bull. Acad. Sci. Cracovie II 1909. 742.
(3) Ambrose , D. , T rans . Faraday Soc. 52, 772 (1956).
(4) Arms t rong , G. T. , Natl. Bur. Std. Rept. 2626 (1953).
(5) Arms t rong , G. T. , J . Res . Natl. Bur. Std. 53, 263 (1954).
(6) Arms t rong , G. T. , Brickwedde, F . G. , and Scott, R. B. , J . Res .
Natl. Bur . Std. 55, 39 (1955).
(7) Baume. G. , and Robert , M. , Compt. Rend. 168 ,̂ 1199 (1919).
(8) Beat t ie , J . A. , and Lawrence, 0 . K. , J . Am. Chern. Soc. 52, 6 (1930).
(9) Bennewitz, K. , and Andreev, N. , Z. Physik. Chem. A142, 37 (1929).
(10) Bennewitz, K. , and Windish, J . J . , Z. Physik. Chem. Al66 , 401(1933).
(11) Berthoud, A. , Helv. Chim. Acta 5, 513 (1922).
(12) Bloomer , O. T. , and Pa ren t , J . D. , Inst. Gas Techn. Res . Bull. 17
(1952).
(13) Booth, H. S. , and Swinehart, C. F . , J . Am. Chem. Soc. 57, 1337(1935).
(14) Bredig, G. , and Teichman, L. , E lek t rochem. M. 449 (1925).
(15) Cardoso, E. , Gazz. Chim. Ital . 5^, 1 (1921).
(16) Cardoso , E. , and Baume, G, , J . Chim. Phys . 10, 509 (1912).
(17) Cardoso , E. , and Fiorent ino, U. , J . Chim. Phys . 23, 841 (1926).
(18) Cardoso , E. , and Germann, A, F . O. , J . Chim. Phys . 10, 517 (1912).
(19) Cardoso , E. . and Germann. A. F . O. , J . Chim. Phys . H , 632 (1913).
(20) Oath, P . G. , and Kammerl ingh Onnes, H. , Koninkl. Ned. Akad.
Wetenschap. P roc . Ser. B. 26, 490 (1917) Leiden Comm. No. 152a.
(21) Clark, A. M. , Din, F . , Robb, J . , Michels , A . , Wassenaar , T. , and
Zwieter ing, Th. N. , Physic a 17, 876 (1951).
- 1 4 1 -
(22) Clark, A. M. , Cockett, A. H. , and E i s n e r . H. S. , P r o c . Roy. Soc.
(London) A209. 408 (1951).
(23) Clegg. H. P . , Rowlinson. J . S. , and Sutton, J . R. . T r a n s . Faraday
Soc. 51, 1325 (1955).
(24) Couch. E. J . , and Kobe, K. A . , J . Chem. Eng. Data 6, 229 (1961).
(25) Cragoe . C. S. . Meye r s , 0 . H. . and Taylor , C. S. . Natl. Bur . Std.
Sci. and Tech. Pape r s 16, 1 (1920) and J. Am. Chem. Soc. 42, 206
(1920).
(26) Crommel in , C. A. , Koninkl. Ned. Akad. Wetenschap. P r o c . Ser . B
22, 1212 (1913) Leiden Comm. Nos. 115a, 138c, 140a.
(27) Dodge, B. F . , and Davis, H. N. , J . Am. Chem. Soc. 49, 610 (1927).
(28) Drozdowski. E. . and P ie t rzak , J . , Bull . Intern. Acad. Sci. Cracovie
A J 9 i 3 , 219.
(29) Franck , E . V . , and Spalthoff, W. , Z . E lek t rochem. 6 j , 348 (1957).
(30) F r i edman , A. S. , and White, D. , J . Am. Chem. Soc. 72, 3931 (1950).
(31) F r i edman , A. S. , and White, D . . J . Am. Chem. Soc. 73. 5713 (1951).
(32) F r i edman , A. S. , White, D. , and Johnston, H. L. . J . Am. Chem. Soc
73. 1310 (1951).
(33) F r i edman , A. S. , White, D. , and Johnston, H. L. , J . Chem. Phys .
^ , 126 (1951).
(34) Giauque, W. F . , and Blue, R. W. , J . Am. Chem. Soc. 58, 831 (1936).
(35) Giauque, W. F . , and Clayton, J . O. , J . Am. Chem. Soc. 54, 2610
(1932).
(36) Giauque, W. F . , and Clayton, J . O. , J . Am. Chem. Soc. 55, 4875
(1933).
(37) Giauque, W. F . , and Powell , T. M. , J . Am. Chem. Soc. 6^, 1970
(1939).
- 1 4 2 -
(38) G i a u q u e , W. F . , and R u h r w e i n , R. A . , J . A m . C h e m . Soc . 6_1, 2626
(1939).
(39) G i a u q u e , W. F . , and Wiebe , R. , J . A m . C h e m . Soc . 50, 101 (1928).
(40) G i a u q u e , W. F . , and Wiebe , R. , J . A m . C h e m . Soc . 50, 2193 (1928).
(41) G i a u q u e , W. F . , and Wiebe , R. , J . A m . C h e m . Soc . 5J , 1441 (1929).
(42) Goodwin, R. D . , D i l l e r , D. E . , R o d e r , H. M. , and W e b e r , L . A . ,
J . R e s . Na t l . B u r . Std. 67A, 173 (1963).
(43
(44
(45
(46
(47
(48
(49
(50
(51
(52
(53
(54
(55
(56
G r i l l y , E . R. , J . A m . C h e m . Soc . 73, 843 (1951).
G r i l l y , E . R. , C r y o g e n i c s 2̂ , 226 (1962).
Habgood , H. W. , and S c h n e i d e r , W. G. , Can . J . C h e m . 32, 98 (1954).
H a r a , R. , and S inozak i , H. , T e c h . R e p t s . Tohoku I m p . Univ. 4, 145
(1924).
H e s t e r m a n s , P . , and Whi te , D . . J . P h y s . C h e m . 65 , 362 (1961).
H i l d e n b r a n d , D. L . , and McDona ld , R. A . , J . P h y s . C h e m . 63 , 1521
(1959).
Hoge , H. J . , J . R e s . Na t l , B u r . Std. 34, 281 (1945),
H o g e , H, J . , J . R e s . Na t l , B u r . Std. 44 , 321 (1950).
Hoge , H, J . , and A r n o l d , R. D , , J . R e s . N a t l . B u r , Std. 47 , 63 (1951).
Hoge , H. J , , and L a s s i t e r , J , W. , J . R e s . N a t l . B u r . Std. 47 , 75
(1951).
H y n e . R. A . , and T i l e y . P . F . . J . C h e m . Soc . (London) 196J. 2348,
" I n t e r n a t i o n a l C r i t i c a l T a b l e s . " Vol . III. M c G r a w - H i l l Book C o m p a n y .
I n c . , New Y o r k , 1928, p p . 2 0 1 - 2 4 9 .
J a r r y , R. L . , and D a v i s , W . , J r . , J , P h y s , C h e m . 57, 600 (1953)
and A m , D o c . 4069 .
J o h n s t o n , H. L, , and G iauque , W. F . , J , A m , C h e m . Soc, 5 1 , 3194
(1929).
-143-
(57) Kang, T. L. , Hir th , L. J . , Kobe. K. A . , and McKetta, J . J . , _J.
Chem. Eng. Data 6, 220 (1961),
(58) Kay, W. B. , and Rambosek, G. M. , Ind. Eng. Chem. 22j[ (1953).
(59) Kelley, K. K. , U, S. Bur . Mines Bull. 383 (1935).
(60) Keyes, F . G. , and Brownlee, R. B. , J . Am. Chem, Soc. 40, 25 (1918).
(61) Keyes, F . G. , Taylor, R. S. , and Smith, L, B. , J . Math, Phys , 1,
211 (1922),
(62) Knietsch, Ann. Chem. 259, 100 (1890).
(63) Kobe, K. A , , and Lynn, R. E. . J r . , Chem. Rev. 52, 117 (1953).
(64) Kopper, H. , Z. Physik. Chem. ALTS, 469 (1936).
(65) Landol t -Bornste in , "Phys ika l i sch-Chemische Tabe l len , " Verlag von
Julius Springer , Berl in , 1923-36, HW 1332-77, IE 721-42, HE 1290-
1310, HIE 2430-62.
(66) Lewis , G. N. , and Randall, M. , " T h e r m o d y n a m i c s , " Second Ed, (Re
vised by P i t ze r and Brewer) McGraw-Hill Book Co. , Inc. , New York,
1961.
(67) Lorentzen, H. C , Acta Chem. Scand. 7̂ , 1335 (1953).
(68) Mathias , E . , and Crommel in . C. A . , Ann. Phys . 5, 137 (1936).
(69) Meihuizen, J . J . , and Crommel in , C. A . , Physica 4, 1 (1937).
(70) M e y e r s , C. H. , and Van Dusen. M. S. , J . Res , Natl. Bur . Std. 10,
381 (1933).
(71) Michels , A , . B la i s se . B. , and Michels , C , P r o c . Roy. Soc. (London)
A160, 358 (1937).
(72| Michels , A , , and Levelt , J . M. , Physica 24. 659 (1958).
(73| Michels , A , , and Wassenaar , T. . Physica 16, 253 (1950).
(74) Michels , A . , Wassenaar , T. , DeGraaf, W. , and P r i n s , C h r . , Physica
19, 26 (1953).
-144-
Michels , A . , Wassenaar , T. , and Zwietering, Th. N. , Physica 18,
63 (1952).
Michels , A . , Wassenaar , T. , and Zwieter ing, Th. N. , Physica 18,
160 (1952).
Michels , A . , Wassenaar , T. , Zwietering, Th. N. , and Smits , P . ,
Physica 16, 501 (1950).
Mi l le r , D. G. . Ind. Eng. Chem. 56, 46 (1964).
Mi l le r , H. 0 . , Verdel l i , L. S. , and Gall, J . F . , Ind. Eng. Chem. 43,
1126 (1951).
Mit tasch, A . , Kuss, E. , and Schlueter , H. , Z. Anorg. AUgem. Chem,
i 5 9 , 1 (1926).
Moles , E. , J . Chim. Phys . 17, 415 (1919).
Nadejine, Bull. Acad. Imp. Sci. St. Pe t e r sburg 30, 327 (1886).
U. S. Natl, Bur . Std. Ci rc , 500 (1952).
Natl. Bur . Std. C i r c . 564 (1955).
Osborne , N. S. , and M e y e r s , 0 . H. , J . Res . Natl. Bur . Std. n , 1(1934).
Osborne , N. S. , Stimson, H. F . , and Ginnings, D. C. , J . Res . Natl.
Bur . Std. 23, 261 (1939).
Otto, J . , and Thomas. W. . Z. Physik. Chem. (Frankfurt) 23, 84 (I960).
Patnode, W. I . , and Papish , J . , J . Phys . Chem. 34, 1494 (1930).
Pa t t e r son , H. S. , Cr ipps , R. S. , and Whytlaw-Gray, R. , P r o c , Roy.
Soc. (London) A86, 579(1912),
(90) Pellatonj M. , J . Chim. Phys . _13, 426 (1915),
(91) P e r r y , J . H. , "Chemical Engineers Handbook," Four th Ed. , McGraw-
Hill Book Company, I n c . , New York, 1963, pp. 3-107.
(92) P e r r y , J . H. , and Bardwell , D, C , J . Am. Chem. Soc. 47, 2629(1925).
- 1 4 5 -
(93) Picker ing , S. F . , J . Phys . Chem. 28, 97 (1924) and Natl. Bur. Std.
Sci. and Tech. Pape r s y . , 597 (1926).
(94) P o r t e r , F . , and P e r r y , J . H. , J . Am. Chem. Soc. 48, 2059 (1926).
(95) Reamer , H. H. , Sage, B. H. , and Lacey, W. N. , Ind. Eng. Chem.
42, 140 (1950).
(96) Regnault, H. V . , Mem, de P a r i s 26, (1862).
(97) Richardson, J . W. , and Smith, P . R, , "E lec t ron Density Shifts Dur
ing Chemical Bond F o r m a t i o n , " presented at the 145th Meeting of the
Amer ican Chemical Society, New York, 1963.
(98) Riedel, L. , Bull. Intern. Inst. Refrig. 20, No. 4, Annex No. 5, B l
(1939).
(99) Ruehrwein, R, A. , and Giauque, W. F . , J . Am. Chem. Soc. 6 j ,
2940 (1939).
(100) Roder, H. M. , Di l ler , D. E. , Weber, L. A . , and Goodwin, R. D. ,
Cryogenics 3, 16 (1963).
(101) Roebuck, J . R. , Mur re l l , T. A , , and Mil ler , E. E. , J . Am. Chem.
Soc. 64, 400 (1942).
(102) Sama, D. A . , M. S. Thes is , Chemical Engineering, Massachusse t t s
Institute of Technology, 1955.
(103) Scheffer, F . E. C , and Treub, J . P . , Z. Physik. Chem. 8Jl, 308
(1913).
(104) Scheffer, F . E . C , and Voogd, M. , Rec . Trav . Chim. 45, 214 (1926).
(105) Schlinger, W. G. , and Sage, B. H. . Ind. Eng. Chem. 42, 2158 (1950).
(106) Schmidt, E. , and Thomas, W. , Fo r sch . Gebeite. IngenJurw 20B, 161
(1954).
(107) Smits , A . , and Schoenmaker, P . , J . Chem. Soc. (London) 1926, 1108.
(108) Stull, D. R. , Ind. Eng. Chem. 39, 517, 1684 (1947).
- 146-
(109) T e r w e n , J . W. , Z . P h y s i k . C h e m . 9 1 , 469 (1916).
(109a) T h o m a s , W. , P r o g . I n t e r n . R e s . T h e r m o d y n a m i c T r a n s p o r t P r o p e r
t i e s ASME Second S y m p o s i u m , 1962.
(110) T o r i u m i , T. , and H a r a , R, , J . Soc . C h e m . Ind. ( Japan) 4 7 . 502(1944) .
(111) W a r i n g , W. , Ind. E n g . C h e m . 46 , 762 (1954).
(112) W e b e r , L . A . , D i l l e r , D. E . , R o d e r , H. M . , and Goodwin, R. D . ,
C r y o g e n i c s 2, 236 (1962).
(113) W e i n b e r g e r , M . A . , and S c h n e i d e r , W. G. , Can . J . C h e m . 30, 422
(1952).
(114) Wentorf , R. H. , J r . , J . C h e m . P h y s . 24, 607 (1956).
(115) W e r t h e i m e r , E . , B e r . Deu t . P h y s i k . G e s . 2 1 , 435 (1919).
(116) Whi t e , D . , F r i e d m a n , A . S. , and J o h n s t o n , H. L . , J . A m . C h e m .
Soc . 72, 3927 (1950).
(117) Whi te , D . , F r i e d m a n , A . S. , and J o h n s t o n , H. L . , J . A m . C h e m .
Soc . 72, 3565 (1950).
(118) Wooley , H. W. , Scot t , R. B . , and B r i c k w e d d e , F . G. , J . R e s . N a t l .
B u r . Std. 4 1 , 379 (1948).
(119) Young, S . , J . C h e m . Soc . 59, 911 (1891).
(120) Young, S . , Sc i . P r o c . Roy. Dubl in Soc . 12, 3 7 4 ( 1 9 0 9 ) .
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