Given below are two statements: Statement I : The dipole moment of R-CN is greater than R-NC and R-NC can undergo hydrolysis under acidic medium to produce : R-CN hydrolyses under acidic medium to produce a compound which on treatment with SOCl _ 2 , followed by the addition of NH _ 3 gives another

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Given below are two statements: Statement I : The dipole moment of R-CN is greater than R-NC and R-NC can undergo hydrolysis under acidic medium to produce : R-CN hydrolyses under acidic medium to produce a compound which on treatment with SOCl _ 2 , followed by the addition of NH _ 3 gives another compound ( x ). This compound ( x ) on treatment with NaOCl / NaOH gives a product, that on treatment with CHCl _ 3 / KOH / produces R-NC. In the light of the above statements, choose the correct answer from the options given below

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Correct answer: B. Statement I is false but Statement II is true

Statement I: The dipole moment of alkyl cyanides (R-CN) is indeed greater than alkyl isocyanides (R-NC) because the C N bond is more polar than the N^+ C^- bond where formal charges oppose the electronegativity difference. However, the acidic hydrolysis of R-NC produces a primary amine (R-NH_2) and formic acid (HCOOH), not a carboxylic acid (R-COOH). Thus, Statement I is false. Statement II: R-CN on acidic hydrolysis gives R-COOH. Treatment with SOCl_2 gives R-COCl. Addition of NH_3 gives R-CONH_2 (compound x). Treatment of R-CONH_2 with NaOCl/NaOH (Hofmann Bromamide Degradation equivalent) gives R-NH_2. R-NH_2 on treatment with CHCl_3/KOH/ (Carbylamine reaction) produces R-NC. Thus, Statement II is true. Therefore, Statement I is false but Statement II is true.

JEE Main Chemistry Question (2026) — Solution

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