Free Energy of Reaction -- Temperature Dependence
2NH3(g) + 3O2(g) + 2CH4(g) 1000°C --------> Pt - Rh 2HCN(g) + 6H2O(g)
The above reaction is used in the industrial production of hydrogen cyanide. Consider the relevant thermodynamic data from the appendices of your text. (The tabulated values ΔH°f and S° are for 25°C. For the purposes of this question assume that ΔH° and ΔS° are invariant with temperature. This is not actually true but would generally be a reasonable approximation over "small" temperature ranges.)
a) Calculate ΔH° for this equation.
-939.8 kJ
b) Calculate ΔS° for this equation.
165 J/K
c) Calculate ΔG° at 787°C, for this equation.