For a gaseous reaction, standard conditions are 298 K and a partial pressure of 1 atm for all species. For the reaction 2NO(g) + O_2(g) rlhar 2NO_2(g) the standard change in Gibbs free energy is delta G degree = -69.0 kJ/mol. What is delta G for this reaction at 298 K when the partial pressures are P_NO = 0.450 atm, P_O_2 = 0.500 atm, and P_NO_2, = 0.850 atm delta G =
Expert Answer
Apply full dG equation
dG = dG º + RT*ln(Q)
Q = P-NO2^2 /(P-NO)^2 * (p-O2)
Q = (0.85^2)/((0.45^2)(0.5)) = 7.1358
now, dGº = -69 kJ = -69000
substitute all data
dG = dG º + RT*ln(Q)
dG = -69000 +(8.314*298)*ln(7.1358)
dG = -64,131.26 J/mol
dG = -64.231 kJ/mol