Question

For the reaction $A\left(g\right)\leftrightharpoons B\left(g\right)+C\left(g\right),K_p$ at ${400}^{\circ }C$ is $1.5\times {10}^{-4}$ and $K_p$ at ${600}^{\circ }C$ is $6\times {10}^{-3}$. Then, which of the following statements is incorrect?

• A. The reaction is an exothermic one.
• B. An increase in temperature increases the formation of $B$.
• C. An increase in pressure increase the formation of $A$.
• D. A decrease in temperature and increase in pressure shifts the equilibrium towards left.

Answer 1

The correct option is A The reaction is an exothermic one.

As the temperature increases from ${400}^{o}C$ to ${600}^{o}C$, the value of the equilibrium constant increases from $1.5\times {10}^{-4}$ to $6\times {10}^{-3}$. This indicates that the reaction is endothermic so that with an increase in temperature, the equilibrium shifts to right, heat is absorbed which nullifies the effect of the increased temperature.

In an endothermic reaction, an increase in pressure shifts the equilibrium towards less mole of gas. So, in the given reaction when pressure is increased the formation of A increases.