If electrolysis of water is carried out for a time duration of 2 hours, how much electric current in amperes would be required to liberate 100 ~ml of O ₂ gas measured under standard conditions of temperature and pressure?

Step-by-step solution

The electrolysis of water produces oxygen gas at the anode according to the reaction: 2H₂O(l) O₂(g) + 4H⁺(aq) + 4e⁻ . From the stoichiometry of the reaction, 4 moles of electrons are required to produce 1 mole of O₂ gas. At standard temperature and pressure (STP), 1 mole of any gas occupies 22.4 liters or 22400 ml. The volume of O₂ given is 100 ml. The number of moles of O₂ produced is n_ O₂ = 100 22400 = 1 224 moles. The total charge Q required is n_ e⁻ F , where n_ e⁻ = 4 n_ O₂ = 4 1 224 = 1 56 moles of electrons