Question

Refining of metals is done by:

• A. heating in presence of air
• B. electrolysis
• C. heating in absence of air
• D. none of these

Answer 1

The correct option is B

electrolysis

Refining of metals is done by electrolysis. Metals like copper, silver, zinc and gold can be obtained by refining in the electrolysis process.
In an electrolytic cell, the impure metal is made anode and a thin strip of pure metal is made cathode. A solution of a suitable salt of the concerned metal is used as the electrolyte. On passing electricity, the anode undergoes dissolution while the pure metal gets deposited at the cathode. Insoluble impurities deposit below the anode in the form of anode mud.