Question

Electrolytic refining is used for refining of:
$A.\;\;\;\;Cu$
$B.\;\;\;\;Fe$
$C.\;\;\;\;Pb$
$D.\;\;\;\;Co$

Answer 1

By the help of electrolysis, the purification or extraction of pure metal can occur. This process is termed as electrolytic refining in which a huge slab of impure metal is used as anode with a thin strip of pure metal at cathode. When we talk about the electrolyte used in this process, we use a metal salt aqueous solution of the metal which is used.

Complete step-by-step answer: We must know that the pure metal at cathode when electrical current is passed which is of a sufficient voltage by dissolving impure metal at anode.
When we talk about refining, we take an example of electrolytic copper which can be understood very clearly. Coal can be mined to extract copper. This extracted copper is called blister copper. This copper is about $99\%$ pure and like this this process can be used to easily extract pure products.
In the copper refining process, impure copper is taken at anode. Anode is a positive electrode. We use electrolyte as copper sulphate. This copper sulphate is acidified with sulphuric acid. Pure copper is obtained at a negative anode called cathode. The electrolysis process causes copper sulphate to break down into a positive ion of copper and negative of sulphate. The positive copper ion $\left( {C{u^{ + + }}} \right)$ or cations travel towards the negative electrode made of pure copper where it absorbs the electrons from the cathode. $Cu$ atom is deposited on the cathode’s graphite layer.

**Thus the correct option is $\left( A \right)$ Copper. **

Note: Graphite is used to coat cathode which causes the concentrate material to be easily removed. Copper has various industrial uses such as its high electrical conductivity and low corrosion level. This causes copper to be used in wires too. It is an excellent alloy and thus it is often used in utensils. It can be moulded easily and has low human toxicity.