Explain zone refining process with an example.

Using the Ellingham diagram,
(A) Predict the conditions under which
(i) Aluminium might be expected to reduce magnesia.
(ii) Magnesium could reduce alumina.
(B) it is possible to reduce Fe₂O₃ by coke at a temperature around 1200K

Explain the electrometallurgy of aluminium.

Explain the following terms with suitable examples.
(i) Gangue
(ii) slag

Give the basic requirement for vapour phase refining.