Question

Which of the following do you expect to react fastest in an SN₂ reaction with cyanide ion?

a) Tertiary alkyl halide
b) Secondary alkyl halide
c) Primary alkyl halide
d) Methyl halide

Answer 1

The methyl halide is expected to react fastest in an SN2 reaction with cyanide ion.

Step-by-step explanation:

In an SN2 reaction with cyanide ion, the rate of reaction depends on the nature of the alkyl halide substrate. The substrate that is expected to react fastest in an SN2 reaction with cyanide ion is a methyl halide. Methyl halides have the highest reactivity in SN2 reactions due to their minimal steric hindrance, allowing the nucleophile (cyanide ion) to attack the carbon atom easily. Cyanide is also one of the most toxic substance.