The equilibrium constant Kc for the reaction N2 (g) + 3H2 (g)⇋ 2NH3 (g) is:
N2 (g) + 3H2 (g)⇋ 2NH3 (g)
We can write Rate of forward reaction, rf = kf [N2]1 [H2]3
And the rate of backward reaction, rb = kb [NH3]2
The equilibrium constant Kp for the reaction N2 (g) + 3H2 (g) ⇋ 2NH3 (g) is: