Aluminium is produced by the electrolysis of aluminium oxide. The diagram shows the electrolysis cell. Which statement about the process is incorrect?
- AAluminium ions gain electrons during the electrolysis and are reduced.
- BCryolite is added to reduce the melting point of the aluminium oxide.
- CThe anode and cathode are made of graphite.
- DThe cathode has to be replaced regularly because it is burnt away.