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JEE Main levelSingle correct optionDifficulty 2 of 3mt177

Electrolytic refining of copper uses acidified copper sulfate solution as electrolyte. Sulfuric acid is added mainly to

Asuppress hydrolysis of $CuSO X_{4}$ and increase the conductivity of the solution
Bmake the cathode deposit porous
Creduce $Cu X^{2 +}$ to $Cu X^{+}$
Doxidise $Zn$ and $Fe$ impurities to solid oxides

Answer: A

Cu X^{2 +}

salts tend to hydrolyse, giving basic salts. Added

H X_{2} SO X_{4}

prevents this and, being strongly ionised, raises the conductivity so the cell works at a low voltage.

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