Question

If the equilibrium constants of a reaction at $298K$ and $308K$ are $1.0\times {10}^{-2}$ and $2\times {10}^{-2}$respectively, then the reaction is:

• A. exothermic
• B. endothermic
• C. may be endothermic or exothermic
• D. cannot be predicted

Answer 1

Answer: (B)

endothermic

We are given that the equilibrium constants of a reaction at $298K$ and $308K$ are $1.0\times {10}^{-2}$ and $2\times {10}^{-2}$ respectively.

With an increase in temperature, the value of the equilibrium constant is also increasing.

This indicates that forward reaction is favoured with an increase in temperature.

This is possible when the forward reaction is endothermic by Le Chatelier's Principle.

Hence, the correct option is $\text{B}$