For a given exothermic reactionKp and Kp' are the equilibrium constants at temperatures T1 and T2, respectively. Assuming that heat of reaction is constant in temperature range between T1 and T2, it is readily observed that
For exothermic reaction, ΔH=-ve i.e. heat is evolved. The temperature T2 is higher than T1 .
Thus, 1T2-1T1 is negative.
so, logKp'-logKp=- ve or logKp>logKp'