Question

Electrolytic refining is used to purify which of the following metals?

• A. $Cu\text{and}Zn$
• B. $Zr\text{and}Ti$
• C. $Ge\text{and}Si$
• D. $Zn\text{and}Hg$

Answer 1

The correct option is A $Cu\text{and}Zn$

Electrolytic refining is mainly used in copper and zinc metal. In this method, the impure metal is made to act as anode. A strip of the same metal in pure form is used as a cathode.

They are put in a suitable electrolytic bath containing soluble salt of the same metal.

The pure metal ions migrate at cathode and get deposited as pure metal and the impurities settle down at anode as anode mud.

Reactions for the Cu metal are:

At anode: $Cu\to C{u}^{2+}+2e^{-}$
At Cathode: $C{u}^{2+}+2e^{-}\to 2e^{-}\to Cu$

So, the correct answer is option (a).