Given the reactions (1) and (2) at 298K below, determine (a) ∆ ⊖ and ∆ ⊖ for reaction (3) at 298K; (b) ∆ ⊖ for both HI(g) and H2O(g) all at 298 K. (1) H2(g) + I2(s) → 2 HI(g) ∆ ⊖ = +52.96 kJ mol-1 (2) 2 H2(g) + O2(g) → 2 H2O(g) ∆ ⊖= -483.64 kJ rnol-1 (3) 4 HI(g) + O2(g) → 2 I2(s) + 2 H2O(g)
