These structures represent which particular kind of halides:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Allylic halides
In both structures the halogen is bonded to an sp3-hybridised carbon next to a C=C double bond (an allylic carbon):
\( \ce{CH2=CH-CH2-X} \): X is on the \( \ce{CH2} \) group attached to the double bond (3-halopropene).
3-Halocyclohex-1-ene: X is on the ring carbon next to the ring double bond.
Compounds of this type are called allylic halides.
Why the other options are incorrect
Option (1) Alkyl halides — Incorrect. In alkyl halides X is on an sp3 carbon of a saturated chain with no neighbouring C=C; these molecules have a double bond next to the C–X carbon.
Option (2) Benzylic halides — Incorrect. X would be on an sp3 carbon attached to an aromatic ring; neither structure has a benzene ring.
Option (3) Vinyl halide — Incorrect. X would be on an sp2 carbon of the C=C itself; here X is on the carbon next to the double bond.
NCERT (2026-27 edition):
Allylic Halides
