Question

Which of the following is deposited at cathode on electrolysis of aqueous NaCl solution?

• A. Chlorine
• B. Sodium
• C. Sodium amalgam
• D. Hydrogen

Hint:

In aqueous NaCl electrolysis: Cathode → H$_2$, Anode → Cl$_2$, Solution remains basic (NaOH formed).

Answer 1

The Correct Option is D

Step 1: Recall electrolysis process.
In aqueous NaCl electrolysis:
- At cathode: Water is reduced more easily than Na\(^+\), producing H$_2$ gas.
- At anode: Cl\(^-\) is oxidized to Cl$_2$.
Step 2: Analyze options.
(A) Chlorine: Produced at anode, not cathode.
(B) Sodium: Not deposited in aqueous solution due to high reduction potential.
(C) Sodium amalgam: Forms in mercury cathode electrolysis, not here.
(D) Hydrogen: Correct — released at cathode.
Step 3: Conclusion.
Therefore, hydrogen is deposited at cathode.