Write down the Reactivity Series from Potassium to Gold. Potassium

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Write down the Reactivity
Series from Potassium to
Gold.
Potassium
Sodium
Lithium
Calcium
Magnesium
Aluminium
Carbon
Zinc
Iron
Tin
Lead
Hydrogen
Copper
Silver
Gold
Platinum
The most reactive is at the top, the least reactive at the bottom.
The Reaction of Iron with Air.
Write the Word Equation.
What is this Slow Reaction called?
• iron
+ oxygen
• rusting.

iron(III) oxide
The Reaction of Magnesium with Steam.
Write the Word Equation.
Is this Reaction Reversible?
• magnesium + steam
magnesium oxide
• No
+ hydrogen
The Reaction of Iron with Dilute
Hydrochloric Acid.
Write the Word Equation.
• iron + hydrochloric acid 
iron(II) chloride
+ hydrogen.
The Reaction of Iron with Copper(II) Sulphate.
Write the Word Equation.
What Type of Reaction is this?
• iron + copper(II) sulphate  iron sulphate +
copper.
• Metal Displacement Reactions.
• A metal will displace (take the place of) a less reactive metal
in metal salt solution.
What would you See during the
Reaction?
• Copper(II) sulphate is blue, iron sulphate is
colourless.
• During the reaction the blue solution loses its
colour
• and the iron metal is seen to turn pink-brown
as the displaced copper becomes deposited on
it.
What is Oxidation?
What is Reduction?
• Oxidation means losing electrons and
reduction means gaining electrons .
• OIL RIG
What is an Ore?
• Metal ore deposits are a finite resource
and non-renewable.
A mineral which contains a high enough
percentage of a metal
for economic extraction is called a metal ore.
When is Carbon used for
Extraction?
• A metal below carbon in the reactivity series
(zinc to silver)
may be extracted from its ore by heating with
carbon.
The metal is displaced from its non-metal anion
by the more reactive carbon.
Carbon is used because it is readily available
and cheap
(coke or charcoal are both carbon).
The metal in the ore is said to be reduced by
reaction with carbon
When is Electrolysis used for
Extraction?
• Metals above carbon in the reactivity
series
(potassium, sodium, lithium, calcium,
magnesium and aluminium)
are extracted by electrolysis.
What is Aluminium Ore called?
• Aluminium ore is called bauxite.
What is the Chemical Formula for
Aluminium Oxide?
• Al2O3.
Why is Cryolite added to
Aluminium Ore?
• The alumina must be molten for electrolysis to
work,
Unfortunately, alumina has a high melting point
(2040 °C)
and it is not practical to do electrolysis at such a
high temperature.
• A solution of alumina in cryolite melts at about
900 °C
and electrolysis is done at about 950 °C.
Which Gases are given off at the
Anode?
• oxygen at the anode.
Why does the Anode need to be
Replaced?
•
Oxygen is given off at the positive carbon anode.
•
Carbon dioxide is also given off at the carbon anode because
hot oxygen reacts with the carbon anode to form carbon dioxide gas.
carbon + oxygen  carbon dioxide.
•
The carbon anodes slowly disappear
because each molecule of carbon dioxide which is given off
takes a little piece of carbon away with it.
•
The carbon anodes need to be replaced when they become too small
Why is Aluminium More
Expensive than Iron?
• Aluminium is the third most abundant element
in the Earth's crust after oxygen and silicon.
It is the most abundant metal but it is more
expensive to produce than iron
because of the cost of the large amounts of
electricity
which are needed for electrolysis.
About half of the aluminium used in the UK is
recycled.
Give two uses of Aluminium.
• 1) is strong, malleable and has a low
density.
2) is resistant to corrosion.
3) is a good conductor of heat and
electricity.
4) can be polished to give a highly
reflective surface.
What is Haematite?
• The main iron ore is called haematite.
Haematite is iron(III) oxide - Fe2O3.
Which three Raw Materials are added
through the Top of the Blast Furnace
?
• Iron ore
• Coke
• limestone
Write the Balanced Equation for
the Combustion of Coke.
• carbon + oxygen 
C(s) +
carbondioxide + heat.
O2(g)
CO2(g)
Which compound Reduces Iron in
the Blast Furnace?
• Carbon monoxide reduces iron in the ore
to iron metal.
Why is Limestone used in the
Blast Furnace?
• Limestone is calcium carbonate (CaCO3)
and it is
added to the blast furnace to remove the
impurities in the iron ore.
What is Thermal Decomposition
of Limestone.
• Calcium carbonate is decomposed by
heat in the furnace
to give calcium oxide (quicklime) and
carbon dioxide.
This is called thermal decomposition
Give one Use of Slag.
• The slag (CaSiO3) is used for road
construction.
In purification of Copper the
Anode made from Pure or Impure
Copper?
• The anode is a block of impure copper.
Which Compound is used as the
Electrolyte during Purification?
• Aqueous copper sulphate
Write the equation for the
Reduction of Copper at the
Cathode.
• Cu(s) - 2e- 
Cu2+(aq)
Give two Uses of Copper.
• 1) Copper is an excellent conductor of
electricity and heat.
2) Copper is soft, easily bent and shaped
(malleable).
3) Copper is resistant to corrosion (very
unreactive).
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