Question

An aqueous solution of CuSO4 is electrolyzed using platinum electrodes.
Which of the following will be observed at the cathode?

• A. Copper metal is deposited.
• B. Hydrogen gas is evolved.
• C. Oxygen gas is evolved.
• D. Copper dissolves.

Hint:

During electrolysis, at the cathode, reduction occurs (metal deposition or hydrogen evolution). At the anode, oxidation occurs (oxygen evolution or metal dissolution).

Answer 1

The Correct Option is A

During the electrolysis of an aqueous CuSO4 solution, copper metal is deposited at the cathode. This is because the copper ions (Cu\(^{2+}\)) are reduced to copper metal (Cu) at the cathode. The half-reaction at the cathode is: \[ Cu^{2+} + 2e^- \rightarrow Cu \] At the anode, oxygen gas is evolved, but the question asks about the cathode, where copper is deposited. Hence, option (A) is the correct answer.