Question

In the presence of a catalyst, the heat evolved or absorbed during the reaction _______.

• (A) Increases
• (B) Decreases
• (C) Remains unchanged
• (D) May increase or decrease

Answer 1

The Correct Option is C

Explanation:
In the presence of a catalyst, the heat evolved or absorbed during the reaction remains unchanged. The enthalpy change value of the reaction will not be affected by a catalyst. A catalyst will only lower the required activation energy for the reactions. Since it will lower the activation energy for both the forward and reverse reactions to the same extent, the net change in enthalpy is zero. Hence, the correct option is (C).