Allyl cholride can be distinguished from Vinyl chloride by NaOH and silver nitrate test. Comment.

Allyl chloride: The Cl atom is bonded to an sp³ -hybridized carbon atom next to carbon-carbon double bond (C=C) i.e. to an allylic carbon. For example:

1.

2. CH₂ = CHCH₂Cl

Vinyl chloride: The Cl atom is bonded to an sp²-hybridised carbon atom of a carbon-carbon double bond (C = C). For example:

1.

2.

As we can see that allyl chloride has a CH₂ group attached to Cl atom whereas vinyl chloride does not have any CH₂ group attached to Cl atom. CH₂ group is responsible for the precipitation (saturation process).

⇒ Hence, on test with NaOH and silver nitrate, allyl chloride gives a precipitate due to the presence of CH₂ group whereas vinyl chloride does not due to absence of CH₂ group.

One more difference is that vinyl chloride does not respond to NaOH and silver nitrate test because of partial double bond character due to resonance.

⇒ In vinyl chloride, chlorine atom is directly attached to doubly-bonded carbon atom. Hence, it shows resonance.

⇒ In allyl chloride, chorine atom is attached to CH₂ group. Hence, it does not show any resonance.