Part A Estimate ΔG°rxn for the following reaction at 387 K. HCN(g) + 2 H2(g) → CH3NH2(g) ΔH°= -158.0 kJ; ΔS°= -219.9 J/K Estimate ΔG°rxn for the following reaction at 387 K. HCN(g) + 2 H2(g) → CH3NH2(g) ΔH°= -158.0 kJ; ΔS°= -219.9 J/K +75.0 kJ -243 kJ -72.9 kJ +72.9 kJ +243 kJ