Question

Give the reactions occurring at cathode and anode during electrolytic refining of copper.

Answer 1

At the anode (oxidation): Copper atoms from the impure block lose electrons and dissolve into the solution as copper ions.

\[\ce{Cu -> Cu^{2+} + 2e^-}\]

At the cathode (reduction): Copper ions from the solution move to the pure copper cathode, gain electrons, and deposit as pure copper metal.

\[\ce{Cu^{2+} + 2e^- -> Cu}\]

Thus, impure copper dissolves from the anode and pure copper is deposited on the cathode.