An electrolysis cell is set up with inert platinum, Pt, electrodes - VCE - SSCE Chemistry - Question 13 - 2022 - Paper 1

In the electrolysis of sodium chloride solution, the cathode reaction involves the reduction of sodium ions (Na⁺) to form sodium metal. However, this does not produce a gas.

In contrast, when sodium chloride is dissolved in water and subjected to electrolysis, chlorine gas (Cl₂) is produced at the anode. The cathode will, however, produce hydrogen gas (H₂) from water due to the following reaction: $2H_2O + 2e^- \rightarrow H_2(g) + 2OH^-(aq)$ Thus, during the electrolysis of NaCl(aq), a gas is produced at the cathode, making option B the correct choice.