Question

Arrange 1°, 2° and 3° haloalkanes in the decreasing order of their reactivity towards nucleophilic substitution reactions.

Answer 1

1. For the (SN₂) mechanism (bimolecular nucleophilic substitution), the order is:
   1° haloalkanes > 2° haloalkanes > 3° haloalkanes
2. For the ( SN₁) mechanism (unimolecular nucleophilic substitution), the order is:
   3° haloalkanes > 2° haloalkanes > 1° haloalkanes