An incorrect statement with respect to `S_(N)1` and `S_(N)2` mechanism for alkyl halide is:

Options

A. A strong nucleophile in an aprotic solvent increases the rate or favours `S_(N)2` reaction
B. Competing reaction for an `S_(N)2` reaction is rearrangement
C. `S_(N)1` reaction can be catalysed by some Lewis acids
D. A weak nucleophile and a protic solvent increases the rate or favours `S_(N)1` reaction

Answer

B

Explanation

`S_(N)1` reaction occurs through the formation of carbocation as intermediate. Hence, rearrangement occur in `S_(N)1` reaction and not in `S_(N)2` reaction. `S_(N)1` reaction is favoured in presence of a polar protic solvent and a weak nucleophile. A strong nucleophile is an aprotic solvent increases the rate of `S_(N)2` reaction.