Question

Which of the following will not be changed by the addition of a catalyst to a reaction at equilibrium?
i. The point of equilibrium
ii. The heat of reaction $\Delta H$
iii. The potential energy of the products

• A. i only
• B. ii only
• C. i and ii only
• D. ii and iii only
• E. i, ii and iii

Answer 1

The correct option is E i, ii and iii

Addition of a catalyst to a reaction at equilibrium will not change the following
i. The point of equilibrium and the value of the equilibrium constant
ii. The heat of reaction $\Delta$H.
iii. The potential energy of the products (and the potential energy of the reactants).
However, the activation energy and the rate of the reaction will change. The catalyst will provide an alternate pathway having lower activation energy. This will increase the rate of the reaction.