Question

Some data are given below :

(Iron tank, Carbon lining, Cryolite, Carbon blocks, Electricity)

1. Identify the metal whose metallurgy is associated here.

2. Explain the extraction of this metal.

Answer 1

1. Aluminium.

2. The alumina is dissolved in a mixture of molten cryolite. It is then electrolysed in a rectangular steel tank, with carbon lining, which serves as cathode. Anode is a set of thick carbon rods suspended from top into the fused Al₂O₃ . The temperature is maintained as 1200 K and 1310 K. Oxygen is evolved at anode which reacts with carbon of anode producing CO and CO₂ . Aluminium formed at the cathode gets collected.