Question

The fluorspar `(CaF_2)` is added in small quantities in the electrolytic reduction of alumina dissolved in fused cryolite `(Na_3 AlF_(6))` . The role of fluorspar is/are
I. to decrease the rate of oxidation of carbon at anode .
II. to act as a catalyst .
III. to lower the temperature of the melt .
IV. to make the fused mixture very conducting .
Choose the correct statement(s).
A. I and II
B. II and III
C. I and IV
D. III and IV

Answer 1

Correct Answer - A
The fluorspar `(CaF_2)` is added in small quantities in the electrolytic reduction of alumina dissolved in fused cryolite `(Na_3AlF_6)` . Fluorspar decreases the rate of oxidation of carbon at anode and also acts as a catalyst .