Question

The sketch below illustrates the refining of aluminium by Hoope's process.
Figure

(a) Which of A and B is the cathode and which one is the anode?
(b) What is the electrolyte in the tank?
(c) What material is used for the cathode?

Answer 1

(a) A (graphite rods) is the cathode and B (impure aluminium) is the anode.
(b) Molten mixtures of fluorides of Na, Al and Ba act as the electrolyte.
(c) Graphite rods are used as the cathode.