Question

What will happen during the electrolysis of aqueous solution of CuSO$$_4$$ by using platinum electrodes?

Answer 1

Correct option is C. Oxygen will be released at anode

During electrolysis following reaction takes place at cathode:

$$Cu^{2+} + 2e^{-} \rightarrow Cu$$

$$H^{-} + e^{-} \rightarrow \frac{1}{2} H_2$$

Standard electrode potential of $$Cu^{2+}/Cu$$ is greater than $$H^- / \frac{1}{2}H_2$$ therefore Cu will deposited at cathode.