How do I calculate reaction free energy?

Calculate the change in free energy (KJ) for the reaction NO(g) + O3(g) → NO2(g) + O2(g)?

• Calculate the change in free energy (KJ) for the reaction NO(g) + O3(g) → NO2(g) + O2(g) under the following conditions: T = 298 K ΔGo = -198.0 kJ/mol Pressure of NO = 1.06 x 10-5 atm Pressure of O3 = 1.44 x 10-5 atm Pressure of NO2 = 2.50 x 10-6 atm Pressure of O2 = 2.25 x 10-2 atm

• Answer:

  use the formula delta G= -RTln K K=(partial pressure of NO2* partial pr of O2)/(partial pr of NO*partial pr of O3) R=8.314J