Solution: Consider the following reaction: CH3OH(g) ⇌ CO(g) + 2H2 (g) Calculate ΔG for this reaction at 25°C under the following conditions: PCH3OH = 0.890 atm PCO = 0.120 atm PH2 = 0.200 atm Δ G =                           kJ

We’re being asked to determine the standard free energy change (ΔG) at 25 ˚C for the given reaction:

CH₃OH(g) ⇌ CO(g) + 2 H₂(g)

Because of the double-arrows, we can say that this is an equilibrium reaction. 

We are given the following equilibrium pressures of each compound:

P_CH3OH = 0.890 atm

P_CO = 0.120 atm

P_H2 = 0.200 atm

Recall that ΔG and K are related to each other:

$\boxed{\mathbf{\Delta G}{\mathbf{°}}_{\mathbf{rxn}}\mathbf{=}\mathbf{-}\mathbf{RTlnK}}$