During electrolysis of alumina, aluminium is deposited at the cathode. Molten aluminium being heavier than the electrolyte, is collected at the bottom of the tank. Oxygen gas is liberated at the anode.
Anode reaction: 2O–– → O2 + 4e– (Oxidation)
Cathode reaction: Al3+ + 3e– → Al(I) (Reduction)
