Question

Which of the following statements regarding catalyst is not true?

• A. A catalyst remains unchanged in composition and quantity at the end of the reaction.
• B. A catalyst can alter the Gibbs free energy change.
• C. A catalyst does not alter the equilibrium in a reversible reaction.
• D. Catalysts are sometimes very specific in respect of reaction.

Answer 1

The correct option is B A catalyst can alter the Gibbs free energy change.

Do you remember the characteristics of a catalyst?

Let me give you a snapshot of it.

Characteristics of a Catalyst:

(i) It only catalyses the spontaneous reaction but not the non-spontaneous reaction.

(ii) It doesn’t change the equilibrium constant, but only helps in attaining equilibrium faster.

(iii) It catalyses both forward and backward reactions to the same extent to maintain the equilibrium state in case of reversible reaction.

(iv) It doesn’t alter the $\Delta G$ (Gibbs energy) of a reaction.

(v) A small amount of the catalyst can catalyze a large amount of reactants.