Explain the principle of the method of electrolytic refining of metals. Give one example.

In this method, the impure metal is made to act as anode. A strip of the same metal in pure form is used as cathode. They are put in a suitable electrolytic bath containing soluble salt of the same metal.

When current is passed through it, the metal ions from solution goes to the cathode and accept electrons and gets deposited on it in metallic form.

In the meantime the equal amount of metal at anode lose electrons and come into the solution.

This continues and the pure strip of metal made as cathode gets thicker while the impure metal electrode gets thinner.

The other impurities gets settled below anode as anode mud.

Metals like Cu, Zn, etc are purified by this method.