1. 31/03/2017
Reactivity of Metals

2. Reactions of metals with oxygen
31/03/2017
When a metal reacts with oxygen it will form a METAL OXIDE. This is what happens when a metal rusts. We can make this reaction happen quicker by burning the metal.
METAL + OXYGEN METAL OXIDE
Copy and complete the following reactions:
Magnesium + oxygen
Copper + oxygen
Calcium + oxygen
Iron + oxygen

3. Reactions of metals with water
31/03/2017
When a metal reacts with water hydrogen is always given off. The other product will be either a metal hydroxide or a metal oxide.
METAL + WATER METAL OXIDE + HYDROGEN
METAL + WATER METAL HYDROXIDE + HYDROGEN
Copy and complete the following reactions:
Sodium + water
Potassium + water
Calcium + water
Iron + steam

4. Reactions of metals with acids
31/03/2017
When a metal reacts with an acid it gives off hydrogen (which can be “popped” using a lit splint). The other product is a salt.
METAL + ACID SALT + HYDROGEN
e.g. magnesium + hydrochloric acid magnesium chloride + hydrogen
Copy and complete the following reactions:
Calcium + hydrochloric acid
Zinc + hydrochloric acid
Iron + hydrochloric acid
Lithium + sulphuric acid

5. Complete the following reactions:
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Lithium + water
Lithium + hydrochloric acid
Silver + oxygen
Magnesium + sulphuric acid
Potassium + oxygen
Aluminium + oxygen
Manganese + water
Sodium + sulphuric acid
Lithium + oxygen
Nickel + hydrochloric acid
Lithium hydroxide + hydrogen
Lithium chloride + hydrogen
Silver oxide
Magnesium sulphate + hydrogen
Potassium oxide
Aluminium oxide
Manganese oxide + hydrogen
Sodium sulphate + hydrogen
Lithium oxide
Nickel chloride + hydrogen

6. An example question on reactivity
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Metal
Reaction with dilute acid
Reaction with water
Reaction with oxygen A
Some reaction
Slow reaction
Burns brightly B
No reaction
Reacts slowly C D
Violent reaction E
Reasonable reaction
Reacts with steam only

7. Increasing reactivity
The Reactivity Series
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Increasing reactivity
Potassium
Sodium
Calcium
Magnesium
Aluminium
Carbon
Zinc
Iron
Lead
Copper
Silver
Gold
The Reactivity Series lists metals in order of reactivity:

8. Displacement reactions
31/03/2017
A displacement reaction is one where a MORE REACTIVE metal will DISPLACE a LESS REACTIVE metal from a compound. Mg
Magnesium
SO4 Cu
Copper sulphate
The magnesium DISPLACES the copper from copper sulphate
SO4 Mg
Magnesium sulphate Cu
Copper

9. Displacement reactions
31/03/2017
A displacement reaction is one where a MORE REACTIVE metal will DISPLACE a LESS REACTIVE metal from a compound.
For example, 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.

10. Some example reactions…
31/03/2017
Reaction
Prediction
Observations
Zinc + copper sulphate
Zinc + lead nitrate
Copper + lead nitrate
Copper + silver nitrate
Extension work – write down the equations for these reactions

11. Some example reactions…
31/03/2017
Reaction
Prediction
Observations
Zinc + copper sulphate
Reaction DID happen
Zinc + lead nitrate
Copper + lead nitrate
Reaction DID NOT happen
Copper + silver nitrate
Extension work – write down the equations for these reactions

12. Extracting Metals Some definitions:
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Some definitions:
A METAL ORE is a mineral or mixture of minerals from which it is “economically practical” to extract some metal.
Most ores contain METAL OXIDES (e.g. rust = iron oxide).
To “extract” a metal from a metal oxide we need to REDUCE the oxygen. This is called a REDUCTION reaction.

13. Increasing reactivity
How do we do it?
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Potassium
Sodium
Calcium
Magnesium
Aluminium
Carbon
Zinc
Iron
Tin
Lead
Copper
Silver
Gold
Platinum
Increasing reactivity
Metals ABOVE CARBON, because of their high reactivity, are extracted by ELECTROLYSIS
Metals BELOW CARBON are extracted by heating them with carbon in a BLAST FURNACE
These LOW REACTIVITY metals blatantly won’t need to be extracted because they are SO unreactive you’ll find them on their own, not in a metal oxide

14. Extracting metals What is an ore?
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What is an ore?
In what form are metals usually found in the Earth?
How do you get a metal out of a metal oxide?
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

15. Iron oxide + carbon monoxide iron + carbon dioxide
The Blast Furnace
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1) HAEMATITE (iron ore), limestone and coke (carbon) are fed in here
2) Hot air is blasted in here
3) The carbon reacts with oxygen from the air to form carbon dioxide.
4) The carbon dioxide reacts with more carbon to form carbon monoxide
5) Carbon monoxide reduces iron oxide to iron. The molten iron is tapped off here
6) Molten slag (waste) is tapped off here
Iron oxide + carbon monoxide iron + carbon dioxide

16. Electrolysis Molecule of solid copper chloride
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Molecule of solid copper chloride
Molecule of solid copper chloride after being dissolved
Chloride ion
Copper ion

17. Electrolysis Electrolysis is used to extract a HIGHLY REACTIVE metal.
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Electrolysis is used to extract a HIGHLY REACTIVE metal.
= chloride ion
= copper ion
When we electrolysed copper chloride the negative chloride ions moved to the positive electrode and the positive copper ions moved to the negative electrode – OPPOSITES ATTRACT!!!

18. These two processes are called REDOX REACTIONS
31/03/2017
These happen during electrolysis:
At the positive electrode the negative ions LOSE electrons to become neutral – this is OXIDATION
At the negative electrode the positive ions GAIN electrons to become neutral – this is REDUCTION
These two processes are called REDOX REACTIONS
OILRIG – Oxidation Is Loss of electrons
Reduction Is Gain of electrons

19. Words – melting point, replaced, negative, bauxite, reactive, move
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Purifying Aluminium
Aluminium has to be extracted from its ore (called ________) by electrolysis. This is because aluminium is very ___________. The ore is mixed with cryolite to lower its ________ ________. The ore is then melted so that the ions can ______. The positively charged aluminium ions gather at the ___________ electrode. Oxygen forms at the positive electrode and causes it to wear away, which means that they have to be __________ frequently.
Words – melting point, replaced, negative, bauxite, reactive, move

20. Rusting Experiment NO RUST – no water NO RUST – no oxygen RUST
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NO RUST – no water
NO RUST – no oxygen
RUST

21. Rusting
31/03/2017
Rust is formed when iron reacts with water AND oxygen. It’s an example of an oxidation reaction which can be sped up using salt. There are several ways of dealing with rust:
Regular painting or oiling
Galvanising – this is when iron objects are coated with zinc
Making objects out of a non-rusting metal, such as stainless steel
Attaching zinc bars to ships – the water will react with the zinc before it reacts with the iron, because zinc is more reactive