Water is formed when hydrogen burns in oxygen.2H2(g) + O2(g) → 2H2O(l) ΔHθr

Water is formed when hydrogen burns in oxygen.

2H2(g) + O2(g)  2H2O(l) ΔHθr = –561.6 kJ–1 mol–1

a. Calculate the entropy change of the system for this reaction.

(Values for Sθin J K–1 mol–1: H2(g) = +130.6, O2(g) = +205.0, H2O(g) = +69.9)

b. Use your answer to part a and the information at the start of the question to calculate a value for the Gibbs free energy change of this reaction.

c. Is the reaction spontaneous at room temperature? Explain your answer.

d. Use your answer to part b to suggest a value for the standard Gibbs free energy of formation of H2O(l). Explain your answer.