Chemistry · Oct / Nov 2018 · Paper 12 · Question 13

Four processes using electrolysis are listed. 1 the electrolysis of concentrated aqueous sodium chloride 2 the electrolysis of dilute sulfuric acid 3 the extraction of aluminium from pure aluminium oxide 4 the purification of copper using aqueous copper(II) sulfate Which processes produce oxygen at one of the electrodes?

1. A1 and 2
2. B2 and 3
3. C2 and 4
4. D3 and 4

As printed in the paper