Question

Which of the following statements about a catalyst is /are true?
A. a catalyst accelerates the reaction by bringing down the energy of activation.
B. A catalyst does not take part in the reaction.
C. A catalyst makes the reaction more feasible by making the ΔG^o more negative.
D. A catalyst makes the equilibrium constant of the reaction more favourable for the forward reaction.

Answer 1

Hint: A substance that functions in altering a reaction's rate is termed a catalyst. It gives an alternate pathway by which a reaction proceeds. Some names of catalysts are manganese dioxide, platinum, palladium, nickel, etc.

Complete Step by Step Answer:
Let's understand what happens with the catalyst addition to a system. The role of the catalyst is to speed up both the forward and the backward reactions. Thus, it helps to achieve the equilibrium state early. But the concentration at equilibrium is not changed, that is, the equilibrium constant is not changed.

Let's discuss the options one by one.
Catalysts provide an alternate pathway by lowering the activation energy of the reaction. Therefore, option A is right.
The role of the catalysts is to make the reaction faster. They actually do not participate in the reaction. Therefore, option B is right.
Catalysts have no impact on the thermodynamic parameters and equilibrium constant. Therefore, C and D are wrong statements.
Hence, A and B are right answer.

Note: Catalysts are classified as positive and negative catalysts. Positive catalysts function in speeding up reaction namely, manganese dioxide, vanadium dioxide, etc. The negative catalysts lower the speed of a reaction, such as platinum.