Metals
Learning Objectives
• Order metals in order of reactivity
• Relate extraction method to reactivity
• Write word/symbol equations for
reduction of metal ores with carbon
Iron
Magnetite
Magnetite (iron oxide Fe3O4)
Hematite (iron oxide, Fe2O3)
Put the metals in order of reactivity
Metal Reaction with Reaction Reaction
dilute acid with water with oxygen
Some reaction Slow reaction Burns brightly
A
No reaction No reaction Reacts slowly
B
No reaction No reaction No reaction
C
Violent reaction Slow reaction Burns brightly
D
Reasonable Reacts with Reacts slowly
E reaction steam only
Displacement reactions
A displacement reaction is one where a MORE REACTIVE metal will
DISPLACE a LESS REACTIVE metal from a compound.
Magnesium Copper sulphate
Mg Cu SO4
The magnesium
DISPLACES the copper
from copper sulphate
Mg SO4 Cu
Magnesium sulphate Copper
Displacement reactions
A displacement reaction is one where a MORE REACTIVE
metal will DISPLACE a LESS REACTIVE metal from a
compound.
E.g. if you drop some magnesium into copper sulphate a
reaction will happen because magnesium is more reactive
than copper, so the reaction is:
Magnesium + copper sulphate copper + magnesium sulphate
However, if you drop some copper into magnesium sulphate
NOTHING will happen.
Extraction methods
Potassium
Sodium
Metals ABOVE CARBON, because
Calcium
Increasing reactivity
of their high reactivity, are
Magnesium extracted by ELECTROLYSIS
Aluminium
Carbon
Metals BELOW CARBON are
Zinc extracted by heating them with
Iron carbon in a BLAST FURNACE
Tin
Lead
Copper These LOW REACTIVITY metals don’t
need to be extracted because they are
Silver SO unreactive you’ll find them on their
Gold own, NATIVE (not in a metal oxide)
Platinum N.B. Cu can sometimes be found native
Reduction with carbon
• Zinc, iron, tin, lead and copper can all be extracted from
their ores by SMELTING.
• Metal ore (usually an OXIDE) is heated to a high
temperature with carbon.
• Carbon competes with the metal for the oxygen and
DISPLACES it.
• This is a REDOX process, the carbon is OXIDISED
(gains oxygen) at the same time the metal ore is
REDUCED (loses oxygen)
Equations
Copper oxide + carbon carbon dioxide + copper
(CuO)
2CuO + C CO2 + 2Cu
Iron oxide + carbon carbon dioxide + iron
(Fe2O3)
2Fe2O3 + 3C 3CO2 + 4Fe
Summary:
Extracting metals
1) What is an ore?
2) In what form are metals usually found in the Earth?
3) How do you get a metal out of a metal oxide?
4) What is this type of reaction called?
Type of metal Extraction process Examples
High reactivity (i.e
anything above carbon)
Middle reactivity (i.e.
anything below carbon)
Low reactivity