Give the ionization reactions of electrolyte used in Hall’s process.

1.	Give the ionization reactions of electrolyte used in Hall’s process. write the reaction at the cathode and the anode. Why the anode has to be replaced in this process?
Answer» The ionization reactions of electrolyte in Hall's process. 1. Cryolite: Na₃AlF₆ ⇌ 3Na⁺ + Al³⁺ + 6F^- 2. Fluorspar: CaF₂ ⇌ Ca²⁺ + 2F^- 3. Alumina: Al₂O₃ ⇌ 2Al³⁺ + 3O^2- The reaction at the cathode and anode are: Cathode: 4Al³⁺ + 12e^-→ 4Al Anode: 6O^2- -12e^- → 6[O] 3O + 3O → 3O₂ The anode has to be replaced from time to time as it gets oxidized by the oxygen evolved at the anode.

Give the ionization reactions of electrolyte used in Hall’s process. write the reaction at the cathode and the anode. Why the anode has to be replaced in this process?

Answer»

The ionization reactions of electrolyte in Hall's process.

1. Cryolite: Na₃AlF₆ ⇌ 3Na⁺ + Al³⁺ + 6F^-

2. Fluorspar: CaF₂ ⇌ Ca²⁺ + 2F^-

3. Alumina: Al₂O₃ ⇌ 2Al³⁺ + 3O^2-

The reaction at the cathode and anode are:

Cathode:

4Al³⁺ + 12e^-→ 4Al

Anode:

6O^2- -12e^- → 6[O]

3O + 3O → 3O₂

The anode has to be replaced from time to time as it gets oxidized by the oxygen evolved at the anode.