What will happen during the electrolysis of aqueous solution of \(CuCl_2\) by using platinum electrodes?
Show Hint
- Cu will deposit at Anode
- \(H_2\) gas will be released at cathode
- \(O_2\) gas will be released at anode
- \(Cl_2\) gas will be released at anode
The Correct Option is D
Solution and Explanation
In electrolysis, reduction happens at the cathode (the species easiest to reduce is discharged) and oxidation happens at the anode (the species easiest to oxidise is discharged). With inert platinum electrodes, the electrodes do not take part in the reaction.
Step 1:
At the cathode, \(Cu^{2+}\) is more easily reduced than water, so copper metal is deposited at the cathode (not hydrogen). This rules out options (A) and (B).
Step 2:
At the anode, the choice is between \(Cl^-\) and water. Because of the high overpotential for oxygen evolution, the concentrated chloride ions are discharged in preference to water, so \(Cl_2\) gas is released at the anode.
Answer: Option (D) — \(Cl_2\) gas will be released at the anode.
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