Geometry of reaction intermediate in `S_(N^(1))` reaction is

Options

A. Tetrahedral
B. Planar
C. Triangular bipyramidal
D. None of these

Answer

B

Explanation

The carbocation intermediate is formed in the reaction rate determining step in `S_(N^1)` reaction is an `sp^(2)` hybridized carbon with trigonal planar molecular geometry. Example:

This allows two different avenues for the nucleophilic attack on either side of the planar structure .
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