Question

Electrolysis is carried out in three cells :

In cell (1) : 1(M) CuSO₄ solution is electrolysed using Pt electrodes.

In cell (2) : 1(M) CuSO₄ solution is electrolysed using Cu electrodes.

In cell (3) : 1(M) KCl solution is electrolysed using Pt electrodes.

Which of the following is/are correct ?

• A. In cell (1) : the pH of the solution is decreased
• B. In cell (2) : the pH of the solution remains constant
• C. In cell (3) : the pH of the solution is increased
• D. All of the given are correct

Answer 1

Answer: (D)

All of the given are correct

Answer 2

In cell (1) : Cathode reaction : Cu²⁺ + 2e ¾® Cu

Anode reaction : H₂O ¾® 2H⁺ + $\frac{1}{2}$O₂ + 2e

In cell (2) : Cathode reaction : Cu²⁺ + 2e ¾® Cu

Anode reaction : Cu ¾® Cu²⁺ + 2e

In cell (3) : Cathode reaction : 2H₂O + 2e

¾® H₂ + 2OH^–

Anode reaction : 2Cl^– ¾® Cl₂ + 2e