Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Haloalkanes react with KCN to form alkyl cyanides as a main product while with AgCN form isocyanide as the main product. Reason (R) : KCN and AgCN both are highly ionic compounds. In the light of the above statements, choose the most appropriate answer from the options given below :

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

(A) is not correct but (R) is correct

Both (A) and (R) are correct but (R) is not the correct explanation of (A)

Haloalkanes and Haloarenes PYQ — JEE Main 2024 · 1 Feb · Shift 1 · Q15 with Solution

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Correct answer: A

Haloalkanes react with cyanide reagents differently depending on the nature of the cyanide compound:

With $\mathrm{KCN}$ , the reagent is predominantly ionic, so free cyanide ion $\mathrm{CN^-}$ is available.
$\mathrm{CN^-}$ $C N^{-}$ is an ambident nucleophile, meaning it can attack through either:
- carbon end: giving alkyl cyanide / nitrile $\mathrm{R-C\equiv N}$
- nitrogen end: giving isocyanide $\mathrm{R-N\equiv C}$

In the case of $\mathrm{KCN}$ , attack occurs mainly through the carbon atom, so the major product is alkyl cyanide.

With $\mathrm{AgCN}$ , the compound is largely covalent. The carbon end is bonded to silver, so nucleophilic substitution occurs mainly through the nitrogen end, giving isocyanide as the major product.

Therefore, Assertion (A) is correct.

Reason says: $\mathrm{KCN}$ and $\mathrm{AgCN}$ both are highly ionic compounds.

This is false because:

So Reason (R) is not correct.

Hence the correct option is:

$\boxed{\text{A: (A) is correct but (R) is not correct}}$

Stored correct answer = A

My derived answer = A

So they agree.