Aluminium is obtained by electrolysis of a mixture of aluminium oxide and cryolite. Which statement is incorrect?
- AThe electrodes are made from graphite.
- BThe formula for aluminium oxide is $\text{Al}_2\text{O}_3$.
- CThe purpose of the cryolite is to lower the melting point of the mixture.
- DThe reaction taking place at the anode is $\text{Al}^{3+} + 3e^- \rightarrow \text{Al}$.