Assertion A : Hydrolysis of an alkyl chloride is a slow reaction but in the presence of NaI, the rate of the hydrolysis increases. Reason R : $\mathrm{I}^{-}$ is a good nucleophile as well as a good leaving group. In the light of the above statements, choose the correct answer from the options given below.

(C) Both A and R are true and R is the correct explanation of A

(D) Both A and R are true but R is NOT the correct explanation of A

JEE Main · 2023 · 24 Jan 2023 · Shift 1 · Haloalkanes and Haloarenes

Assertion A : Hydrolysis of an alkyl chloride is a slow reaction but in the presence of NaI, the rate of the hydrolysis increases.
Reason R :

I^{-}

is a good nucleophile as well as a good leaving group.
In the light of the above statements, choose the correct answer from the options given below.

(A)A is false but R is true
(B)A is true but R is false
(C)Both A and R are true and R is the correct explanation of A✓ Correct
(D)Both A and R are true but R is NOT the correct explanation of A

Answer: (C)

Solution

Alkyl chlorides hydrolyse slowly because chloride is a poor leaving group. Iodide added as sodium iodide first behaves as a strong nucleophile and displaces chloride to form the alkyl iodide; the resulting carbon–iodine bond then breaks easily during hydrolysis because iodide is an excellent leaving group. Both the nucleophilic and the leaving-group ability of iodide are needed for the rate to rise, so the assertion is true, the reason is true, and the reason is the correct explanation of the assertion.

JEE Main · 2023 · 24 Jan 2023 · Shift 1 · Single correct option

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JEE Main · 2023 · 24 Jan 2023 · Shift 1 · Haloalkanes and Haloarenes

Solution

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