Question

When an aqueous solution of sodium chloride is electrolyzed using platinum electrodes, the ions discharged at the electrodes are:

• A. sodium and hydrogen
• B. sodium and chloride
• C. hydrogen and chloride
• D. hydroxyl and chloride

Answer 1

The correct option is C hydrogen and chloride

Electrolysis of aqueous sodium chloride yields hydrogen and chlorine, with aqueous sodium hydroxide remaining in solution.

The reason for the difference is that the reduction of $N{a}^{+}$ (E° = –2.7 V) is energetically more difficult than the reduction of water (–1.23 V).