Q1: If the pH value of a solution of sodium chloride is 7; then what will be the pH value of the solution after its electrolysis ?

ANS:C - >7

The pH value of a solution of sodium chloride (NaCl) is 7 because NaCl is a neutral salt. However, during electrolysis, water molecules are split into hydrogen ions (H⁺) and hydroxide ions (OH⁻) at the electrodes. This process affects the pH of the solution. At the anode (positive electrode), water molecules oxidize to produce oxygen gas and release protons (H⁺): 2H₂O(l) → O₂(g) + 4H⁺(aq) + 4e⁻ At the cathode (negative electrode), water molecules reduce to form hydrogen gas and hydroxide ions (OH⁻): 2H₂O(l) + 2e⁻ → H₂(g) + 2OH⁻(aq) The net result is the production of additional H⁺ ions and OH⁻ ions in the solution. However, since the number of H⁺ ions produced equals the number of OH⁻ ions produced, the solution remains neutral. Therefore, the pH value of the solution after electrolysis of sodium chloride would also be >7.