To calculate the Gibbs free energy change G for the reaction, we first need to find the change in enthalpy H and the change in entropy S for the reaction. 1. Calculate H for the reaction:H = Hf products - Hf reactants For the products, we have 2 moles of H2O l , so:H products = 2 * -285.8 kJ/mol = -571.6 kJFor the reactants, we have 2 moles of H2 g and 1 mole of O2 g , both with Hf = 0 kJ/mol, so:H reactants = 2 * 0 kJ/mol + 1 * 0 kJ/mol = 0 kJNow, we can find H for the reaction:H = -571.6 kJ - 0 kJ = -571.6 kJ2. Calculate S for the reaction:We are given S[H2O l ] = -69.9 J/Kmol. However, we need the entropy change for the entire reaction. Since we don't have the entropy values for H2 g and O2 g , we cannot directly calculate S for the reaction.3. Calculate G for the reaction:Since we don't have the entropy change for the reaction, we cannot use the equation G = H - TS directly. However, we know that the reaction of hydrogen and oxygen to form water is spontaneous under standard conditions, which means G must be negative. Therefore, the Gibbs free energy change for the reaction is negative, but we cannot determine the exact value without the entropy change for the reaction.