For iodine gas [I_2(g)], Delta H_f degree = 62.4 kJ/mol and S degree = 260.7 J/mol-K. Calculate the equilibrium partial pressures of I_2(g), H_2(g), and HI(g) for the system 2HI(g) H_2(g) + I_2(g) at 500 degree C if the initial partial pressures are all 0.200 atm.