Electrolysis

Question 1

Explain why electrolysis cannot be conducted on solid ionic substances

Answer 1

They don’t conduct electricity

Question 2

Name the products of the electrolysis of molten iron bromide

Answer 2

Iron an Bromine

Question 3

In electrolysis, what types of substances can be electrolytes?

Answer 3

Ionic compounds that have been melted or dissolved in water

Question 4

In the electrolysis of solutions, what is produced at the anode?

Answer 4

A halogen ( group 7 metal ) or oxygen ( when there is no halogen present )

Question 5

Explain why graphite is often used for the electrodes

Answer 5

It conducts electricity and is relatively unreactive

Question 6

Explain why the anode needs to be continually replaced in the electrolysis of the aluminium oxide

Answer 6

Oxygen is produced at the anode.
The oxygen reacts with the anode, which is made of carbon.
Which forms carbon dioxide.
Causing the anode to wear away (combust)

Question 7

Give the two main disadvantages of using electrolysis to extract metals.

Answer 7

Requires a large amount of energy to melt the compounds and
to produce the necessary electrical current.

Question 8

Explain why aluminium oxide is mixed with cryolite when extracting aluminium by electrolysis.

Answer 8

To lower the melting point.

Question 9

State the purpose of electrolysis

Answer 9

To separate ionic compounds into its elements

Question 10

Give an ionic equation for the breakdown of water in the electrolysis of solutions.

Answer 10

H20 (l)= H+ (at) + OH- (aq) - ( the symbols - 2,+,- - they are actually small )