Which of the following methods is used for refining impure metals?

Question

Question

This question was previously asked in

RRB Technician Grade III Official Paper (Held On: 29 Dec, 2024 Shift 1)

Answer 1

The correct answer is Electrolytic refining.

Key Points

Electrolytic refining is a method used to purify impure metals by using electrolysis.
In this process, the impure metal is made the anode, and a pure metal strip is made the cathode.
An electrolyte solution containing the metal ions is used to facilitate the transfer of metal ions from the anode to the cathode.
As a result, the pure metal is deposited on the cathode, while impurities either fall off as anode mud or remain in the solution.
This method is commonly used for refining metals like copper, nickel, lead, and zinc.

Additional Information

Electrolysis is the process of using an electric current to drive a non-spontaneous chemical reaction.
In electrolytic refining, the energy supplied by the electric current helps in the separation of pure metal from its impurities.
Anode refers to the electrode where oxidation occurs, while the cathode refers to the electrode where reduction occurs.
Anode mud is the insoluble impurities that collect at the bottom of the electrolytic cell during the refining process.
This method ensures high purity levels of the refined metal, often exceeding 99.9% purity.