Properties of metals
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Metals physical properties includes:
they are;
Ductile; they can be drawn into wire,
Malleable; they can be hammered into sheets
Have a high melting point they also have
high density,
 good conductors of electricity and heat
 Metals chemical properties include;
 Reaction with water,
 most reactive metals (K-Ca) react with cold
water, fairly reactive metals (Mg-Fe) will only
react with steam whereas the least reactive
metals (Sn-Pt) don’t react at all.
 Reaction with dilute acids,
 Most reactive metals (K-Ca) reacting
violently, the fairly reactive metals (Mg-Pb)
reacting gradually more slowly and the least
reactive metals (Cu-Pt) not reacting at all.
 Displacement Reactions
 The reactivity of metals relates to how easily
they form ions, more reactive metals like K
form K+ ions much more easily than less
reactive metals like Cu can form Cu+ ions.
 A more reactive metal will reduce a less
reactive metal
Alloys
 Alloys are ‘mixtures of two or more
 Alloys are often harder than the
metals’ (although sometimes they
can contain a non-metal) that are
made by mixing molten metals
 Alloys often have very different
properties to the metals they are
made from
 by varying their properties, metals
can be tailored to have specific
desirable properties – this is called
metallurgy
metals they are made from.
 In pure metals atoms are neatly
lined up meaning they can slip past
each easily when hit.
 In alloys there are atoms of different
sizes which don’t line up neatly so
can’t slip past each other so easily
making them harder.
Some uses of Alloys
Alloy
Properties
Uses
Brass
(Copper + Zinc)
Stronger than copper but still
malleable, gold coloured, shiny &
does not corrode
To make musical instruments,
door knobs, locks & ornaments
Bronze
(Copper + Tin)
Very hard
To make moving parts of
machines, bells, statues etc.
Stainless Steel
(Iron + Chromium+ Nickel)
Does not rust like Iron
To make cutlery, car parts, surgical
instruments etc.
Reactivity series
 In a reactivity series, the most reactive element
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Increase in reactivity
 MOST REACTIVE
 Potassium, K
 Sodium, Na
 Calcium, Ca
 Magnesium, Mg
 Aluminium, Al
 (Carbon, C)
 Zinc, Zn
 Iron, Fe
 Tin, Sn
 Lead, Pb
 (Hydrogen, H)
 Copper, Cu
 Silver, Ag
 Gold, Au
 Platinum, Pt
 LEAST REACTIVE
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is placed at the top and the least reactive
element at the bottom.
More reactive metals have a greater tendency
to lose electrons and form positive ions.
metals above hydrogen reacts with dilute acids,
to produce salt and hydrogen gas.
metals below hydrogen will not react with
dilute acids
K, Na, Ca & Mg react with cold water forming
an alkali solution and hydrogen gas
Zn & Fe react with steam forming metal oxide
and hydrogen gas
The vigour of the reaction decreases down the
reactivity series
more reactive metals will reduce the less
reactive metals i.e. will displace them from
their compounds
Extraction of metals
 Rocks that contain a significant amount of
 metals below carbon on reactivity series
a metal are called ores.
 Metals occur in ores as compounds – often
oxides or sulphides of the metal.
 Examples;
e.g. Zn, Fe & Pb are extracted by using
carbon to reducing oxides of metals
 Example:
 PbO(s) + C(s) →
Pb(s) + CO(g)
 lead is extracted from an ore called galena
 Carbon monoxide is produced in the
(PbS, lead sulphide).
 Iron is extracted from an ore called
Haematite (Fe2O3, Iron III oxide).
 Aluminium is extracted from an ore called
bauxite (Al2O3, Aluminium oxide).
furnace and used for extraction of metal
 Example;
 The method of metal extraction depends
on the position of the metal on the
reactivity series
 metals above carbon on reactivity series
e.g. Al, Mg & Ca are extracted by
electrolysis.
→ 2CO(g)
 ZnO(s) + CO(g) →
Zn(s) + CO2(g)
 2C(s) + O2(g)
Extraction of iron in the blast furnace
 Iron is less reactive than carbon so it extracted
by using carbon to reduce it’s oxide, this is done
in a blast furnace
 Step 1: Carbon (coke) reacts with oxygen (from
the hot air blast)
 C(s) + O2(g)
→
CO2(g)
 Step 2: Carbon dioxide reacts with more carbon
to make carbon monoxide
 CO2(g) + C(s) →
2CO(g)
 Step 3: Carbon monoxide reduces the iron
oxide (iron ore) to make molten liquid iron.
 Fe2O3(s) + 3CO(g) →
2Fe(l) + 3CO2(g)
 The limestone (CaCO3) reacts with impurities
such as silicon to form an easy-to-collect waste
called slag (calcium silicate, CaSiO3):
 CaCO3(s) +SiO2(l)
→ CaSiO3(l) + CO2(g)
 The liquid slag is run off at the bottom and it is
used as a building material in road construction
Uses of metals
 Metals have many uses including:
 Aluminium– and its alloys used for
aircraft as they have low density
and great strength
 Aluminium– is used for food
containers (drink cans, cooking foil
& food cartons) as it is non-toxic,
can be rolled into sheets and
resistant to corrosion
 Aluminium– is used for overhead
electricity cables since it is a good
conductor of electricity, ductile &
resists corrosion
 Zinc – is used to protect steel either
by coating it (galvanising) or as
sacrificial protection to protect it
from rusting
 to galvanise steel, a steel object is
dipped into liquid zinc for zinc to
form a coating on the surface of
steel
 in sacrificial protection, a lump of
zinc is attached to the ship’s hull to
prevent rusting as it is more reactive
than steel so it corrodes instead of
the steel hull