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Q.
The organic chloro compound, which shows complete sterochemical inversion during a $S_{N^2}$ reaction, is
AIEEEAIEEE 2008Haloalkanes and Haloarenes
Solution:
$S_{N^2}$ reaction is favoured by small groups on the carbon atom attached to halogen. So, the order of reactivity is $CH_3Cl > (CH_3 ) 2CHCl > (CH_3 ) 3CCl > (C_2H_2)_2 CHCl$