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 $\mathrm{AgCN}$ form isocyanide as the main product.
Reason (R) : $\mathrm{KCN}$ and $\mathrm{AgCN}$ both are highly ionic compounds.
In the light of the above statements, choose the most appropriate answer from the options given below :
Solution
$\begin{aligned} & \mathrm{R}-\mathrm{X}+\mathrm{KCN} \longrightarrow \mathrm{R}-\mathrm{CN}+\mathrm{KX} \\\\ & \mathrm{R}-\mathrm{X}+\mathrm{AgCN} \longrightarrow \mathrm{R}-\mathrm{NC}+\mathrm{AgX}\end{aligned}$
<br/><br/>$\mathrm{KCN}$ is ionic so it provides cyanide ions in solution and attacks from carbon side on alkyl halide.
<br/><br/>But $\mathrm{AgCN}$ is covalent it cannot form cyanide ion so it attacks from nitrogen side and isocyanide is formed predominantly.
<br/><br/>$\mathrm{A}$ is correct $\mathrm{R}$ is not correct.
About this question
Subject: Chemistry · Chapter: Haloalkanes and Haloarenes · Topic: Nomenclature and Properties
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