Question

Explain the principle of the method of electrolytic refining of metals by giving an example.

Answer 1

Principle of the method of Electrolytic refining-

Electrolytic refining is the method of using electricity to refine impure metals. In this process, the anode is made of impure metal, and the cathode is made of a strip of pure metal. A solution is made with a soluble salt of the same substance as the electrolyte. When an electric current is transmitted, metal ions from the electrolyte are deposited as a pure metal in the cathode, and the impure metal from the anode dissolves in the form of ions into the electrolyte. Below the anode, the impurities metals are collected. It is called mud anode. In the electrolytic refining of copper, the electrolyte is a solution of acidified copper sulphate. The anode is impure copper, whereas the cathode is a strip of pure copper on passing electric current, pure copper is deposited on the cathode.