Four electrolysis processes are given below. 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 generate oxygen at one of the electrodes?
- A1 and 2
- B2 and 3
- C2 and 4
- D3 and 4