Which of the following is Incorrect to explain catalytic activity of the transition metals and their compounds?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Strengthening of the bonds in the reacting molecules
A transition metal catalyst weakens the bonds in the reacting molecules, which lowers the activation energy. “Strengthening of the bonds” is the opposite, so it does not support catalytic activity.
Option (1) Ability to adopt multiple oxidation states — A reason for catalytic activity. The metal can change its oxidation state and so take part in electron transfer.
Option (2) Ability to form complexes — A reason for catalytic activity. The reactants form temporary bonds (complexes) with the metal or its compound.
Option (3) Lowering of activation energy — A reason for catalytic activity. The new reaction path through the catalyst has a lower activation energy.
Option (4) Strengthening of the bonds in the reacting molecules — Not a reason. The bonds are weakened, not strengthened.
NCERT (2026-27 edition):
Catalytic Properties
Note: The same/similar question has been asked in different years by NTA as per the details given below:
| 2026 | 2025 | 2024 | 2023 | 2022 |
|---|---|---|---|---|
| 31-05 S2 11-05 S1 | – | – | – | – |