What volume of gaseous H2 (at STP), when combined with excess O2 in the fuel cell, is needed to prod — Electrochemistry Chemistry Question

💡 Solution & Explanation

The maximum useful work obtainable from the fuel cell under standard conditions equals the magnitude of the standard Gibbs free energy change (ΔG°). Given ΔG° = -237.39 kJ/mol of H2O produced (which consumes 1 mole of H2). To produce 23.739 kJ of work, exactly 0.10 moles of H2 are required. The volume of 0.10 moles of an ideal gas at STP (using the modern 22.7 L/mol standard for 1 bar) is 0.10 × 22.7 = 2.27 L.