Velocity of the `S_(N^(2))` reaction depends on the concentration of the substrate as well as te nucleophile.
The reaction is favoured by strong `Nu^(overset(..)(ө))`, and in the presence of polar aprotic solvent, optically active halides give walden inversion by `S_(N^(2))` mechanism. the presence of hetro group (atom as `beta-C` atom, unsaturation at `beta-C`, and `(-overset(O)overset(||)(C)-)` Allyl halides also give `S_(N^(2))` mechanism. EDG at ortho-and para-positions in benzyl halides favours `S_(N^(1))` mechanism, whereas EWG favours `S_(N^(2))` mechanism.
Q. In the reeaction
, [X] is
A. `C_(2)H_(5)Br`
B.
C.
D. `CH_(2)=CH_(2)`
