H2O2 can be prepared by successive reactions: 2NH4HSO4 -> H2 + (NH4)2S2O8; (NH4)2S2O8 + 2H2O -> 2NH4 — Electrochemistry Chemistry Question
Question
H2O2 can be prepared by successive reactions: 2NH4HSO4 -> H2 + (NH4)2S2O8; (NH4)2S2O8 + 2H2O -> 2NH4HSO4 + H2O2. The first reaction is an electrolytic reaction and second is steam distillation. What amount of current would have to be used in first reaction to produce enough intermediate to yield 102 g pure H2O2 per hour. Assume current efficiency 50%.
💡 Solution & Explanation
Molar mass of H2O2 = 34 g/mol. Rate of H2O2 production = 102 / 34 = 3 mol/hour. Each mole of H2O2 requires 1 mole of (NH4)2S2O8, which requires 2 Faradays of charge to produce via electrolysis. Theoretical charge required = 3 mol/h × 2 F/mol = 6 F/hour = 6 × 96500 C/hour. Theoretical current = (6 × 96500) / 3600 = 160.83 A. With 50% current efficiency, actual current = 160.83 / 0.50 = 321.67 A. Therefore, correct answer is B.