A catalyst increases the rate of reaction by:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Decreasing the activation energy with unchanged equilibrium state
A catalyst forms temporary bonds with the reactants and is given back unchanged at the end. It provides an alternative pathway of lower activation energy, so a larger fraction of the molecules has enough energy to react and the reaction becomes faster.
Why the other options are incorrect
Option (1) Decreasing the Gibbs energy with unchanged equilibrium state — Incorrect. \( \Delta G \) depends only on the initial and final states, which the catalyst does not change; that is why a catalyst cannot make a non-spontaneous reaction take place.
Option (2) Increasing the Gibbs energy and changing the equilibrium state — Incorrect. A catalyst changes neither the Gibbs energy nor the position of equilibrium.
Option (4) Decreasing the activation energy and changing the equilibrium state — Incorrect. The first half is right, but because the forward and backward rates rise equally, the equilibrium state stays the same.
NCERT (2026-27 edition):
Effect of Catalyst – …
Note: The same/similar question has been asked in different years by NTA as per the details given below:
| 2026 | 2025 | 2024 | 2023 | 2022 |
|---|---|---|---|---|
| – | 28-05 S1 | – | – | 17-08 S1 |