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MODEL PAPER 4 — Chemistry STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceChemistryMODEL PAPER 41 Mark
Question
Assertion $(A):$ Isopropyl chloride is less reactive than $\ce{CH_3Br}$ in $S_N2$ reactions.
Reason $(R): SN^2$ reactions are always accompanied by inversion of configuration.
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Answer

As the size of the alkyl groups increases, the $S_N2$ reactivity decreases, further $C - Cl$ bond is stronger and more difficult to cleave than $C - Br$ bond. So $\ce{CH_3Br}$ is more reactive than $\ce{(CH_3)_2CHCl.}$

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