Which of the following is an example of electrochemical principles of metallurgy?
Answer & explanation
Correct answer: option 4
The Hall-Heroult method uses electrochemistry to transform bauxite into almost pure aluminium. Bauxite is kept at a high temperature while being dissolved in a molten electrolyte made of sodium, fluorine, and aluminium. In this procedure, oxygen gas accumulates at the anode and aluminium at the cathode.