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Q.
Which reaction result in the formation of a pair of enantiomers?
Haloalkanes and Haloarenes
Solution:
Reaction (a) & (c) goes via $S_{N} 2$ mechanism. Reaction (b) & (d) proceeds via $S _{ N }$ l mechanism. $S _{ N } 1$ involves formation of a planar carbocation $\&$ hence formation of a pair of enantiomer results, provided the carbon bearing the leaving group becomes chiral after the nucleophillic attack: