What is an electrolytic cell? Give its uses.

(N/A) An electrolytic cell is a device in which an external source of voltage is used to drive a non-spontaneous chemical reaction. In this cell,external electrical energy is converted into chemical energy.
Uses: Electrochemical processes are widely used in laboratories and chemical industries. Some key uses are:
$(i)$ Purification of metals: For example,impure copper is refined to high-purity copper. The impure metal acts as the anode,which dissolves upon passing $DC$ current,while $Cu^{2+}$ ions from the solution are reduced and deposited on the cathode.
$(ii)$ Production of metals: Metals such as $Na, Mg,$ and $Al$ are produced by the reduction of their respective metal ions. Sodium and magnesium are obtained by the electrolysis of their molten chlorides,while $Al$ is produced by the electrolysis of aluminium oxide in the presence of cryolite.