Question

For a given exothermic reaction $K_P$ and $K_P^{\prime }$ are the equilibrium constants at temperatures $T_1$ and $T_2$ respectively. Assuming that heat of reaction is constant in temperature range between $T_1$ and $T_2$ is readily observed that__________.

• A. $K_p>K_p^{\prime }$
• B. $K_p=\frac{1}{K_p^{\prime }}$
• C. $K_p=K_p^{\prime }$
• D. $K_p<K_p^{\prime }$

Answer 1

The correct option is A $K_p>K_p^{\prime }$

Given

Kp is equilibrium constant at T1

Kp' is equilibrium constant at T2.

Solution

The equilibrium constant at two different temperatures is given by

$log\frac{K_p^{{}^{\prime }}}{K_p}=\frac{\Delta H^0}{2.303R}(\frac{1}{T_1}-\frac{1}{T_2})$

For exothermic reaction T1 < T2

Therefore Kp > Kp'

The correct option is A