Question

$NaOH$ is prepared by the electrolysis of

• A. aqueous solution of sodium chloride with platinum electrode
• B. sodium chloride solution with graphite anode and iron cathode
• C. sodium carbonate with platinum electrodes
• D. sodium carbonate with nickel electrodes

Answer 1

Answer: (B)

A sodium chloride solution contains Na⁺ , Cl^- , H⁺ and OH^- ions. On passing electricity, Na⁺ and H⁺ move towards cathode and Cl^- and OH ^- ions towards anode. The discharge potential of H⁺ is less than Na⁺ , therefore hydrogen ions get discharged easily similarly at anode, Cl^- ions easily discharged as Cl₂ . Solution becomes rise in Na⁺ and OH^- ions.