Calculate ΔrG° for the following reaction:
CO2(g) + 3H2(g) -> CH3OH(g) + H2O(g)
Use the following reactions and given ΔrG° values:
CO(g) + H2O(g) -> CO2(g) + H2(g) ΔrG° = -50 kJ/mol
3H2(g) -> CH3OH(g) ΔrG° = -120 kJ/mol

A) -180 kJ
B) -70 kJ
C) 70 kJ
D) 180 kJ