The molecule with largest C-X bond length is
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → \( CH_3-I \)
The length of a covalent bond depends on the sizes of the two bonded atoms. Down group 17 the size of the halogen atom increases, fluorine being the smallest and iodine the largest. So the carbon-halogen bond length increases from C–F to C–I, and the bond also becomes weaker in the same order.
So the molecule with the largest C–X bond length is methyl iodide, \( \ce{CH3-I} \).
NCERT (2026-27 edition):
Nature of C-X Bond – …
Note: The same/similar question has been asked in different years by NTA as per the details given below:
| 2026 | 2025 | 2024 | 2023 | 2022 |
|---|---|---|---|---|
| – | 03-06 S1 30-05 S1 | – | – | – |