Question

Electrolysis of aqueous sodium chloride solution will form ______ at the cathode.

Options

• hydrogen gas

• sodium metal

Answer 1

Electrolysis of aqueous sodium chloride solution will form hydrogen gas at the cathode.

Explanation:

In an aqueous solution of sodium chloride, both sodium ions (Na⁺) and hydrogen ions (H⁺ from water) migrate toward the cathode. Since hydrogen has a much higher reduction potential than sodium, H⁺ ions are preferentially reduced by gaining electrons to liberate hydrogen gas (H₂). Sodium ions remain unchanged in the solution, combining with leftover hydroxyl ions to form sodium hydroxide.