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CONCEPT DIAGRAM ("Mind Map") OF TOPICSome students find that memorizing the OUTLINE of a topic helps them learn and remember the concepts and
important facts. As you proceed th rough the topic, come back to this page regularly to see how each b it f its the
whole. At the end of the notes you will find a blank version of this "Mind Map" to practise on.
History of
Metal Use
Metal
Extraction
Needs Energy
Metal Reaction with
Oxygen
Water
Acids
The Activity Seriesof the Metals
MetalsWe Use
Today
Chemical Activity
of the
Metals
Electron Transfer
REDOX
Our Use of
Metals
Activity & Usage
of Metals
METALS
Patterns
of the
Periodic Table
History of the
Periodic Table
Extracting
Metals
from
Ores
QuantityCalculations
Definition
of the Mole
Conductivity
Melting Points Chemical Bonding
Valency
Reactivity
Atomic Radius1st Ionization
Energy
Electronegativity
Minerals
Ores
&
Resources
Case Study:
Extracting
Copper
from its Ore
Molar Ratios
in
Reactions
The Case for Recycling
Metals
Gay-Lussac's Law
&
Avogadro's Hypothesis
Mole Quantity
Calculations
Masses
Gas Volumes
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The First Uses of MetalsFor most of human existence, people used tools of stone,
wood and bone. Primitive tribes were familiar with gold
which occurs uncombined in nature, but it i s too soft to be
useful for anything but jewellery and decoration.
About 5,000 years ago, in the Middle East, some people
accidentally discovered that if certain rocks were roasted by
fire, small amounts of copper would be found later i n t he
ashes. Copper is too soft to be reallyuseful, but there was
a brief "Copper Age" around the eastern end of the
Mediterranean Sea. Copper was used for decoration,
jewellery, small utensils, and occasionally for knives and
spear points.
The big breakthrough was the discovery by these copper-
using people that if they roasted copper-bearing rocks
(ores) with tin ores, the resulting "alloy" (mixture) of
copper and tin produced a much harder metal, "bronze",
which could be cast in moulds, and hammered to shape
many useful tools and weapons ... this was the start of
The Bronze Age (approx 4,500 to 2,500 years ago)
It is no accident that the rise of the great ancient
civilizations occurred about this time. The stone blocks of
the pyramids and temples of ancient Egypt were cut and
shaped with bronze chisels. Egyptians, and later Greeks,
dominated their world because their soldiers were armed
with bronze swords, spears and arrowheads.
With bronze tools they built better ships and wagons for
transport and trade, which brought wealth and power.
Sad as it might be, t he f acts of human history are that
progress has been marked by conflict, war and conquest,
and metals have been a vital part of that development.
Metal has many advantages over stone, wood, or b one:
metal is harder, stronger, and flexible, not brittle.
metal can be cast, hammered or drawn into shapes not
possible in stone, such as saw blades, swords and armour.
when tools become blunt, metal can be re-sharpened.
Basically, a warrior with a bronze sword always beats a
bloke with a stone axe ... we call that progress!
The Iron Age (approx. 2,500 to 1,500 years ago)
About 1,000 B.C. the extraction of iron from its ores was
discovered. This requires much higher temperatures, and
t he br eakthrough was probably t he invention of t he
bellows, a device to pump air into afurnace so the wood or
charcoal burns hotter.
Iron is stronger and harder than bronze. A warrior armed
with iron weapons will usually beat a bronze-armed man.
Iron t ools and even the humble nail allowed new
developments in buildings, ships, wagons. .. remember that
towns, trade and commerce givewealth and power. An iron
plough allows more land to be cultivated to grow more
food, to feed a bigger army... and so on.
It is no accident that the dominant world power of this
time was ancient Rome, because their technology was
based on iron.
From the Medieval to the Modern
After the collapse of the Roman Empire the variouscultures that dominated the "Dark Ages" still had iron-
based technologies.
The next great technological change was the "Industrial
Revolution" which b egan about 1750 in England. This
had many aspects, but the big change in technology was the
use of coal (instead of wood) for fuel. As well as steam
engines, coal allowed for large scale smelting of iron and
the invention of steel (an alloy of iron with carbon).
The engines, tools and machinery of the great factories
were based on steel. Transport was revolutionized by steel
locomotives running on steel rails. Steel ships replaced
wooden ones, and steel weapons (machine guns, tanks and
artillery) achieved new heights (depths?) in warfare and
mass destruction.
In the 20th century, new metals and alloys became available...
aluminium, titanium, chromium, and many more.
This was made possible by electricity, which is needed in
large amounts to extract some metals from their ores, or to
purify and process them once extracted.
Human Progress has always been linked
to our use of Metals.
Progress in metal usage has always been linked
to the availability of energy to extract the metals.
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The Metals We Use TodayIn one sense, we are still in the "Iron Age". Iron is still the
metal we use the most, but nearly always it is mixed with
other elements in a variety of alloys, notably steel.
Steel isused for bridges, tools and machinery, bolts, screws
and nails, reinforcing inside concrete structures, engines,
vehicle bodies, trains and their rails, ships, and "tin" cans.
Iron ore occurs in huge deposits, so iron is common and
economical to produce.
Steel (in its various forms) is very hard and strong.
It can be cast, milled, rolled, worked, bent, cut and
machined into just about any shape or size imaginable.
As always, our usage of the different steel alloys is linked to
their particular properties:
Steel Iron, Properties Uses
Alloy with ...
Mild steel 0.2% strong, but car bodies,
carbon malleable pipes, roofing
Tool steel 1-1.5% very hard drills, knives,
carbon hammers
Stainless 20% nickel resists food utensils,Steel & chromium corrOSIon, medical tools
hygenic
Brass
is a common "non-ferrous" (no iron) alloy.
Brass is very hard, but easilymachined for screw threads, etc.
It is more expensive than steel, but is corrosion resistant, so
it is ideal for taps and fittings forwater and gas pipes.
Solder
is an alloy of 30-50% tin with lead.
Its most notable property IS a very low melting point,
around 150-200C.
Its major use is in plumbing for sealing the joints between
pipes,. and in electronics for connecting small components
on a"circuit board".
Metals That Are Used in Their Pure State
Although we use a wide range of alloys, there are some
important metals we use in their pure, elemental state.
Aluminium
is very lightweight, yet strong and corrosion resistant
Its lightweight strength is perfect
for aircraft construction.
Lightweight and a good conductor,
it is used for electricity power lines.
Malleable and corrosion resistant, it
is ideal for window frames and drink cans.
Copper
is used for electrical wiring in building s and appliances,
because of its great electrical conductivity and its ductility
for ease of wire-making.
Metal Extraction Needs EnergyAs mentioned previously, our use of diff erent metals
through history can be linked to the availability of energy.
In topic 1, you learned about the process of chemical
decomposition; where a compound breaks down intosimpler substances.
Decomposition is generally an endothermic process;
energy is absorbed by the reactants during the reaction.
Generally, you must supply energy to make the process
happen.
Metal ores are mineral compounds. To obtain the elemental
metal involves decomposition, which is endothermic and
requires energy. Some compounds require more energy
than others for decomposition.
Copper and tin ores require little energy. A decent wood
fire can "smelt" the metal from its ore. TIllS why copper
and bronze were used in ancient times.
Iron ore requires more energy for decomposition. That's
why the "Iron Age" came later.
Aluminium and other "modern" metals require even more
energy, and electricity works better than heat, so these only
became available in quite recent times.
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Before metals, people used tools mainly madefrom a)............................. or .
The fIrst metal used was probably
b) , because it occurs i n the
elemental state in nature. However, it is too softto be used for tools, so was just used for
c) .
Metallurgy (the technology of metals) began withthe extraction of d) from ores
that were simply e) .
A big improvement was the mixing of ores of
f) and .
This produced the alloyg) ,
which made tools and weapons with many
advantages over stone: metal ish) and .
and isnot i) like stonemetal can made into intricate shapes, such as
j) : ,not possible in stone.
Later, bronze was replaced by k) .
which is1) and ,
but requires more m) for
its extraction.
During the "Industrial Revolution", the use of
n) for energy led to the production of
0) which is iron with a small
amount of p)................................ in it. This
allowed the development of machinery, trains
and the modern industrial world.
In the 20th century new metals such as
q) became availablebecause the
r) needed to extract it from its
s) was available.
Today,the metal weuse most is still t) ,in the form of the alloyu) Its
widespread useisbecause:
it is common and v) to
produce.
it is very w) and .
Steel comes in a variety of alloys, including
x) steel (car bodies, pipes, roofIng)
and y) steel used for foodutensils and medical tools.
Other alloys used widely include:
brass, amixture of z) and .
aa) , with a verylowmelting
point, is an alloy of ab) and
.................................... and is used in
ac) and .
As well as many alloys, there are some metalscommonly used in their pure, elemental form:
Aluminium, which has the advantages of beingad)................................. and resistant to
ae) .Uses include af) .
and .
ag) is used for electrical
wiring because of its good
ah) and because it is
ai) so it is easyto draw out into
wues.
Chemically, the extraction of metals from ores
involves aj) .
reactions, which are ak) -thermic. Some
metals, such as al).................................... require
very little energy, others such as
am) require muchmore. In many cases an) .
works better than heat in the extraction and
purifIcation processes. The changes in
ao) usage through history can be
directly linked to society's changing sources and
uses of ap) .
WHEN COMPLETED, WORKSHEETS
BECOME SECTION SUMMARIES
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Metals React With OxygenOne of the most familiar laboratory reactions 1S the
burning of magnesium:
Magnesium + Oxygen ~ Magnesium oxide
2 Mg + 0z ----.. 2 MgO
In fact, many metals will burn, some alot more readily and
violently than magnesium:
Sodium + Oxygen --.-4 Na + 0z --..
Sodium oxide
2 NazO
In these cases there is a violent exothermic reactio n, with
light and heat energy produced. The product is often a
powdery, crumbly solid.
Other metals, such as alumin ium and zinc, react on the
surface and the oxide compound formed is airtight and
pr~vents further reaction. That's why these metals are often
dull-looking ... the surface coat of oxide is dull.
Aluminium + Oxygen2Al + 30z
~ Aluminium oxide
----.. 2 AlZ03
Other metals, such as copper, react with oxygen very slowly
and only if heated strongly. Some, like gold, will not react
at all.
T he point is, that
metals have diff erent chemi cal activities.
Metals React With Water
Another favourite school reaction is when sodium reacts
with water. This is often done outdoors, because it results
in an exciting little explosion.
What happens is:
Sodium + Water ----.. Hydrogen(gas)
2 Na + 2 HzO . Hz
+ Sodiumhydroxide
+ 2NaOH
(In fact this is NOT the explosion reaction. The explosion
is the reaction of the hydrogen with oxygen, to f orm water)
Once again, some metals react easily and rapidly and form
the metal h)7droxide, while others react slowly if heated insteam, and form oxides.
Zinc + W ater ~ Hydrogen + Zinc oxide
Zn + HzO ~ Hz + ZnO
Metals W{ecopper and gold do not react at all.
There is an "Activity Series" among the metals.
Metals React With AcidsThe different activity levels of tl le metals is most clearly
seen when metals are reacted with dilute acids.
You may have done experimental work to observe howvigorously different metals react with a dilute acid.
Metals like calcium and
magnesium react vigorously.
When there is a reaction, the
gas produced ishydrogen.
The metal is "eaten away" and
dissolves into the liquid. This is
because it forms a soluble ionic
compound. Exactly what the
compound is, depends on which acid is used.
Zinc + H ydrochloric ~ Hydrogen + Zincacid chloride
Zn + 2HCI ~ Hz + ZnClz
Magnesium + Nitric ~ Hydrogen + Magnesiumacid nitrate
Mg + 2 HN03 ~ Hz + Mg(N03h
Iron + Sulfuricacid
Fe + HZS0
4
+ Iron(II)sulfate
+ FeS04
The ionic compounds formed are collectively known as
"salts", so the general pattern of the reactions is
I Metal + Acid
It will help you greatly to learn
the common laboratory acids
Common Name Chern Name
H yd ro chlo ri c Hyd ro gen c hlo ri de
SulfurIC Hydrogen Sulfate
Nitric Hydrogen nitr ate
Formula
HCI
HzS04HN03
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The Activity Series of the Metals
From these 3 patterns of reaction, i t seems there is a
further, underlying pattern. Certain metals, like sodium,
always seem to reac t readily and vigorously. Others, like
copper, always react slowly or not at all.
From this, aItd other reaction studies, the common
laboratory metals can be arranged in an "Activity Series":
Most
Active
Mg
AI
Ag
Au
Least
Active
The highly active metals all lie to the extreme left of the
table, AND the h igher their activity, the lower down the
table they are within each column.
This is one of many patterns that allows you to use the
Periodic Table instead of learning many small facts. For
example, instead of memorizing the Activity Series fully,
you can remember the pattern above and always be able to
figure out the order of the most active metals.
Northmead High School SL#603217
Electron Transfer in Metal Reactions
The chemical reactions that allow us to see the pattern of
the Activity Series are just part of an even greater pattern
in Chemistry ... the process of electron transfer.
To understand this, look again atthe reaction between a
metal and an acid:
Zinc + Hydrochloric ~ Hydrogen + Zincacid (gas) chloride
HCl and ZnClz are both ionic compounds. Here is the
equation re-written to show the individual ion "species".
IZn + 2B+ + 2Cr ------ B, + Zn +> + 2CrStudy this carefully and m ake sure you understand why
there have to be 2 of some ions to agree with the original
balanced equation.
Notice that the chloride ions (Clj occur on both sides of
the equation unchanged. Nothing has happened to them at
all. We say they are "spectator ions". Like by-standers at a
car crash they are not involved, while other atoms and ions
undergo serious changes.
Since they aren't actually i nvolved, we can leave the
spectators out. This is called a "net equation".
Now we can see what really happened;
a zinc atom became a zinc ion
and 2 hydrogen ions became a (covalent) hydrogen
molecule.
To do this, the zinc atom has to lose 2 electrons, and the
hydrogen ions must gain a pair of electrons to share.
Now it should be clear what reallyhappened: the zinc atom
gave a pair of electrons to some hydrogen ions. Electrons
were transferred from one "species" to another.
The equations above are "Half-Equations" and are often
used to describe what is reallyhappening in a reaction.
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Oxidation and Reduction
The transfer of e lectrons from one species to another is
one of the most fundamental and important general
reactions of Chemistry.
The reaction between zinc and acid can be visualized like
this:
electrons transferred
~::;;::::~' G)
Zinc atom 2 Hydrogen ions
~
0;0I
Covalent bond(2 electrons being shared)
For historical reasons,
the loss of electrons is called "Oxidation"
The zinc oxidation allows the hydrogen to be reduced, and
the hydrogen reduction allows the zinc to be oxidized.
T he total reaction is an "Oxidation-Reduction" and is
commonly abbreviated to "REDOX".
Note that the syllabus does NOT r equire you to know
these defInitions yet, but it is worth knowing about Redox
for future topics. You ARE required to know about
electron transfer and " its involvement in metal reactions.
Northmead High School SL#60321 7
First Ionization EnergyAlthough you're not yet required t o kn ow ab out
Oxidation and Reduction, this bit you have to learn.
Definition
The Ionization Energy of an element is the energy
required to remove an electron from an atom.
For technical reasons, the measurement of this energyis carried out for atoms i n the gas state.
+----.- Zn (g) + e -
The energy required for this to happen is the
"1st Ionization Energy"
We know that zinc atoms normally lose 2 electrons to
form the Zn +2 ion. However, the formal defInition for
this process involves just the loss of 1 electron.
Every element has it s o wn characteristic value, eventhose elements which would not normally lose
electrons, such as non-metals like chlorine.
Normally a chlorine atom forms a negative ion
by gaining an electron.
Technically though, it is possible for it to lose
an electron if energy is added.
This energy is the "1st Ionization Energy"
Even the inert gases, which normally d o no t form ions
at all, can be forced to lo se an electron if energy is
added. They too have a 1st Ionization Energy value.
Ionization Energy Determines the Activity Series
Now back to the metals a n d the Activity Series.
In order for a metal to begin reacting with an acid, (or
with water or oxygen) it must lose an electron. Tlus will
require the input of its 1st Ionization Energy.
If the value for 1st Ionization energy is very low, the
metal will gain this energy easily and quickly from its
surroundings. It will readily enter the reaction, and the
reaction will proceed vigorously.
If its value for 1st IOluzation energy is higher, the atom
cannot react so readily or vigorously ... its activity is
lower.
The ACTIVITY SERIES of t he Metals
is determined by
1st IONIZATION ENERGY
K...Q)
c NaL.Uc
0
Li.~.~c
Ba.2
AIc
VI
rUZnQ)...
u
E
Fe
Sn
Ph
Cu
Ag
Au
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Choice of MetalsBased on ActivitySometimes which metal is chose n fo r a p arti cular
application is based o n i ts position in the Activity Series.
Example
In critical electronic connections, su ch as computer
network pl ugs, it is essential that the electric signals get
through w itho ut loss or distortion.
Normally we us e copper for electrical winng, but in a
critical connection plug it is worth the extra expense of
using gold.
Copper is a low activity metal, but can slowly react with
oxygen to form a non-conducting oxide layer in the
connection. Go ld is l ower down the activity series and will
not react at all, s o the plug connection cannot corrode.
Gold's extremely low chemical activity (due to a relatively
high 1st Ionization Energy) is part of the reason it h as
always been used for jewellery.
Gold's low activity means it will not tarnish or corrode, so
it retains its beautiful colour and lustre.
Steel is cheap, but since iron
is about the middle of the
Activity Series it will
corrode (rust) by contact
with water. Is it better to
choose alower activity metal
such as copper, which will
not corrode as quickly, but is
more expensive?
The decision is usually to
use cheap steel pipes for
longer, outdoor uses like
your garden taps.
Indoors, where distances are
shorter, and a rusted-out
leaking pipe would b e a
disaster inside awall or
ceiling, copper is chosen,
especially for hot water
supply.
Interestingly, sometimes the higher activity metals corrode
less. Aluminiu m an d zinc are higher up the Activity Series
than iron. They react rapidly when exposed to oxygen, but
the surface layer of oxide is airtight and waterproof , and
prevents oxygen or water getting to the m etal underneath.
Therefore, these metals can be used in situations where
corrosion needs to be prevented.
"Galvanized" steel is coated with a thin layer of zinc to
prevent (or slow down) corrosion of steel roofIng, fence
wires, nails, bolts, etc.
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When a metal reacts with oxygen it forms an a) .
compound.
I METAL + OXYGEN b) \
Some metals will also react with water, forming
c) gas and a d) .
compound.
I METAL + WATER --..c) + d) I
Most metals will react with acids, forming e) .
gas and an ionic compound called a ") "
I METAL + ACID ~ e) + ) ,
In all these reactions t he various metals react at
g) rates, showing an order of chemical
h) Fr om these reactions and others,
the "Activity Series" has been determined.
Metals such as i) and .
are the most active. These are the elements located in the
j) columns of the Periodic Table.
Some metals such as k) and .
have very low activity, and often do not react at all. Other
common metals like 1) and
.................................... are in t h e middle of the series. They
will react, but generally do s o m) .
All these reactions involve the transfer of n) .
In the case of the Metal + Acid reaction, the metal atoms
always 0)........................... electron(s) while a pair of
p) ions gain 2 electrons (which they
share in a q) bond) and form a
r) molecule with formula s) .
"Oxidation" is the technical term for t) .
................................. The opposite is "u) .
In the Metal + Acid reaction, the metal is alwaysv) while w) ions
are always x) .
The "1st y) Energy" of an element is
defined as the energy required to z) .
............................... from atoms in the aa) state.The very active metals are like that because they have very
ab) (high/low) values for tllls. Metals
further down the series do not react as vigorously because
their values are ac) .
Sometimes the choice of which metal to use is determined
by the activity level. An example is ad) .
1. Write a balanced, symbol equation for the reaction of
each of the following metals with oxygen.
a)Lead
(assume lead(IV) ion forms)
b) Iron
(Assume iron(III) ion)
2. a) Arrange the m etals in Q1 in or der of decreasing
chemical activity.
b) Which one(s), if any, might ignite easily and burn in
air with a visible flame?
3. Write a word equation AND a balanced, symbol
equation to describe the reaction of:
a) calcium metal with water (reacts spontaneously at room
temperature)
4. All the following equations are Metal + Acid reactions.Fill in all blank spaces, then re-write in symbols and
balance.
b) Calcium + Hydrochloric ~ + .acid
c) + ~ Hydrogen + Bariumnitrate
d) + ~ Hydrogen + iron(II)chloride
5. For each of the reactions in Q4, wlllch chemical species
a) lost electrons?b) gained electrons?
c) was a "spectator"?
WHEN COMPLETED, WORKSHEETS
BECOME SECTION SUMMARIES
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Atomic Structure, Number and Mass
Here is a quick reminder of some basics about atoms you
need to know:
In the Nucleus are
Protons &
x'.," .Neutrons ..................... '"
;' :.' " ,- .. .
, '\.::/\,n DebitaeDund..... t he nucleus a re
the Electrons
E ach element's atoms have a different, characteristic,
number of protons and electrons. Therefore, each elementhas a different Atomic Number.
In the Periodic Table t he elements are arranged i n order of
Atomic Number.
No.Protons + No.Neutrons = "Mass Number"(Electron mass is insignificant)
The M ass N umber is always a whole number, but in the
Periodic Table the "Atomic Weight" is shown instead.
(How and why this i s different will be explained in a later
topic)
The Periodic Table
is firstly a list of the elements, arranged i n o rd er, a nd
showing all the basic details.
Atomic Number
18 Equal to the number of electronsand the number of protons in
each atom
ArArgon ..
"Atomic Weight"
NOT the "Mass Number"
The shape and arrangement of t he Periodic Table is a very
clever device to allow many patterns and grouping s to b e
accommodated. You have already learnt one pattern in the
position of the most active metals, and their 1st Ioniza tion
Energies.
History of the Periodic Table
The modern concept of a chemical element as a substance
containing identical atoms was first accepted almost exactly
200 years ago.
By 1830 there were about 40 known elements. Even with
such a small sample, people began to notice patterns:
Dobereiner (German) pointed out that there were several
groups of 3 elements witl1.remarkably sinlliar properties:
Lithium, sodium & potassiu m was one "triad".
Chlorine, bromine and iodine formed another "triad".
By 1860, with over 60 known elements, Newlands
(English) proposed a "Law of Octaves".
If the elements were arranged in order of r elative weights,
Newlands found that every 8th element (an "octave" ) was
sinlliar in properties. These similar elements included
Dobereiner's triads.
The s ystem worked well for the first 20 elements, but then
became confused.
The basis of the modern Periodic Table was developed by
the Russian, Dmitri Mendeleev in 1869.
Mendeleev used many physical and chemical properties:
atomic weight density
melting point formula of oxide compound
density of oxide and many more,
and arranged the elements in order of weight, but with
elements with sinlliar properties under each other.
Mendeleev's genius was to realiz t hat there were probably
missing elements that hadn't een d iscovered yet. He
cleverly lef t gaps in his table f or these undis covered
elements.
The most famous case was that of the "missing" element
Mendeleev called "eka-silicon" . He us ed the patterns in his
table to predict, very precisely, the properties for eka-
silicon. Scientists went looking for such a substance and
soon found a new element (which was named
"Germanium") with properties almost exactly as predicted.
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Patterns of the Periodic Table
In Mendeleev's day no-one could explain why these patterns existed.
However, when scientists see patterns in nature like this, they know there must be underlying "r ules" or
"laws of nature" causing and controlling the patterns.
Perhaps Mendeleev's great contribution was not just the Periodic Table itself,
but the stimulus it gave other scientists to investigate the reasons behind the patterns.
Within 40 years Science had unravelled the secrets of atomic structure, the electron energy levels, and more.
At this s ta e our task is to lear n s ome of the atter ns.
Electrical Conductivity
As you go across any row ("period") of the table, you will
move through anumber of metals, then one or two semi-
metals, then into the non-metals.
Therefore, the conductivity will start out high, but r apidly
decrease as you encounter a semi-metal, and becomeextremely low at the non-metals.
r!, I
CLJ\ I i
llj~H~~tJTEI1:1
Boiling Points
follow a similar pattern to
Melting Points
Valencies are the same
down each group
Melting Point
You learned in topic 1 how melting point is determined by the
bonding within a substance.
At the left side of the table are the very active metals of d1e
Activity Series. They are also usually soft, and have relatively low
(for metals) melting points.
Moving to the right across a period you enter d1e "Transition
Block" containing typical hard, high melting point metals, held
strongly together by "metallic bonding".
Further right you hit d1e Semi-Metals. These often have very high
melting points because of their covalent lattice structure.
Then you enter d1e Non-Metals which have covalent molecular
structures and quite low mp's. At the far right column, each period
ends with an Inert Gas which are all s ingle-atom molecules, and
have d1elowest mp of each period.
This pattern repeats itself along each period.
Melting Points of ElementsIII
I
Peaks are Transi ti on M etals
or Semi-Metals
Sketch Graph.oooN
Go~ooo... -
c-
oc..
010
Nac
Chemical Bonding, Valency & Reactivity
What you've already learnt about the Activity Series, Ionic and Covalent Bonding and Valency
will help you make sense of the following: ("" G 8 I Group nert ases
No chemical reactions,
no bonding
Activity of Non-Metals
Most active at top-right(FIuori ne)
Activity (generally)decreases downwardsand to the left.