Question

Name and explain the most widely used method for refining impure metals.

Answer 1

The most widely used method for refining impure metals is electrolytic refining.
In electrolytic refining, an impure metal is made the anode (positive electrode), and a thin strip of pure metal is made the cathode (negative electrode). Both electrodes are placed in a solution containing soluble salts of the metal being refined (electrolyte). On passing electric current through the electrolyte, the impure metal at the anode dissolves, releasing metal ions into the solution. Simultaneously, pure metal ions from the solution deposit onto the cathode. Impurities either remain in the solution as ions or collect as anode mud (at the bottom of the anode).