Question

In the electrolysis of molten NaCl using inert electrodes, what will be observed at the electrodes?

• A. Sodium deposited at anode, chlorine at cathode.
• B. Sodium deposited at cathode, chlorine at anode.
• C. Hydrogen gas at cathode, chlorine at anode.
• D. Sodium deposited at anode, oxygen at cathode.

Hint:

In electrolysis, remember that reduction occurs at the cathode (metal deposition or hydrogen evolution), and oxidation occurs at the anode (gas evolution or metal dissolution).

Answer 1

The Correct Option is B

Sodium metal is produced at the cathode during the electrolysis of molten NaCl with inert electrodes, where reduction takes place. Concurrently, chlorine gas is liberated at the anode, the site of oxidation. The electrode half-reactions are delineated as: At the cathode (reduction): \[ Na^+ + e^- \rightarrow Na \quad \text{(Sodium is deposited)} \] At the anode (oxidation): \[ 2Cl^- \rightarrow Cl_2 + 2e^- \quad \text{(Chlorine gas is evolved)} \] Therefore, the observed phenomena are the deposition of sodium at the cathode and the evolution of chlorine gas at the anode.