The equilibrium constant for the reaction H2 + at 1 atm and 1500C is given to be

Question:

The equilibrium constant for the reaction H2 + at 1 atm and 1500°C is given to be K. Of the reactions given below, all at 1500°C, the reaction that has a different equilibrium constant is
(a) H2 + 12O2 → H2O at 5 atm
(b) 2H2 + O2 → 2H2O at 1 atm
(c) H2 + O2 → H2O + 1/2O2 at 2 atm
(d) H2 + 1/2O2 + 3N2 → H2O + 3N2 at 5 atm
(e) H2 + 1/2O2 + 3N2 →H2O + 3N2 at 1 atm