Why alumina is dissolved in Cryolite for electrolysis?

Ans.

1. Alumina is a bad conductor of electricity in the solid state.
2. The melting point of alumina is very high (>2000⁰C)
3. It is very expensive to carry out the electrolysis at this temperature.
4. Therefore, alumina is dissolved in molten Cryolite for electrolysis.