In the correct of the Hall-Heroult process for the extraction of `Al`, which of the following statements is false ?

Options

A. CO and `CO_(2)` are produced in the process.
B. `Al_(2)O_(3)` is mixed with `CaF_(2)` which lowers the melting point of the mixture and brings conductivity.
C. `Al^(3+)` is reduced at the cathode to form Al
D. `Na_(3)AlF_(6)` serves as the electrolyte

Answer

D

Explanation

(i) In Hall- Heroult process for extraction of Al, carbon anode is oxidised to CO and `CO_(2)`.
(ii) When `Al_(2)O_(3)` is mixed with `CaF_(2)`, it lowers the melting point of the mixture and brings conductivity.
(iii) `Al^(3+)` is reduced at cathode to form Al.
(iv) `Al_(2)O_(3)` serves as the electrolyte, undergoing the redox process. `Na_(3)AlF_(6)` although is an electrolyte but serves as a solvent, not electrolyte.