Question

For a reaction taking place in a container in equilibrium with its surroundings, the effect of temperature on its equilibrium constant $K$ in terms of change in entropy is described by

• A. With increase in temperature, the value of $K$ for exothermic reaction decreases because the entropy change of the system is positive
• B. With increase in temperature, the value of $K$ for endothermic reaction increases because unfavourable change in entropy of the surroundings decreases
• C. With increase in temperature, the value of $K$ for endothermic reaction increases because the entropy change of the system is negative
• D. With increase in temperature, the value of $K$ for exothermic reaction decrease because favourable change in entropy of the surroundings decreases

Answer 1

Answer: (B), (D)

With increase in temperature, the value of $K$ for exothermic reaction decrease because favourable change in entropy of the surroundings decreases
With increase in temperature, the value of $K$ for endothermic reaction increases because unfavourable change in entropy of the surroundings decreases

In case of endothermic reaction, K value increase with increase in temperature and decrease with decreases in temperature whereas in case of exothermic reaction, K value decrease with increase in temperature and increase with decreases in temperature.

When the surrounding loss heat, the entropy of surrounding decreases and so is the system. When it gain heat, entropy increases.

When heat is given to the system from surrounding, system gain the heat and surrounding loss the heat and when system give away the heat, heat of the system decrease but heat of surrounding increase.