JEE Main 2024 Chemistry question
A constant current was passed through a solution of AuCl₄⁻ ion between gold electrodes. After a period of 10.0 minutes, the increase in mass of cathode was 1.314 g. The total charge passed through the solution is × 10⁻² F. (Given atomic mass of Au = 197)
Answer: 2
Solution
Au³⁺ + 3e⁻ → Au. Moles of Au deposited = 1.314/197 = 6.67 × 10⁻³, so the charge is 3 × 6.67 × 10⁻³ = 0.02 F = 2 × 10⁻² F.