Question:

The number of \(\sigma\)-bonds, \(\pi\)-bonds and lone pairs of electrons present in the product C respectively are \[ C_2H_5NO_2 \xrightarrow{Sn/HCl} A \xrightarrow[\text{Heat}]{CHCl_3+KOH} B \xrightarrow{H_2O} C \]

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Carbylamine reaction forms isocyanides from primary amines. Hydrolysis of isocyanides gives formamides.
Updated On: Jul 29, 2026
  • 10,1,3
  • 8,3,2
  • 9,2,3
  • 9,1,3
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The Correct Option is C

Solution and Explanation

Step 1: Identify compound A Given: \[ C_2H_5NO_2 \] This is nitroethane: \[ CH_3CH_2NO_2 \] Reduction with: \[ Sn/HCl \] converts nitro group into amino group. \[ CH_3CH_2NO_2 \rightarrow CH_3CH_2NH_2 \] So, \[ A=\text{Ethylamine} \]

Step 2: Reaction with \(CHCl_3+KOH\) This is: Carbylamine reaction Primary amine forms isocyanide. \[ CH_3CH_2NH_2 \rightarrow CH_3CH_2NC \] So, \[ B=\text{Ethyl isocyanide} \]

Step 3: Hydrolysis of isocyanide Hydrolysis gives: \[ CH_3CH_2NHCHO \] which is: N-ethyl formamide So, \[ C=CH_3CH_2NHCHO \]

Step 4: Count bonds and lone pairs Structure: \[ CH_3-CH_2-NH-CHO \] Sigma bonds: C-H bonds: \[ =6 \] C-C bond: \[ =1 \] C-N bond: \[ =1 \] N-H bond: \[ =1 \] N-C bond: \[ =1 \] C=O has: \[ 1\sigma \] Total sigma bonds: \[ =9 \] Pi bonds: Only in carbonyl: \[ =1 \] But due to resonance in amide: \[ C-N \] has partial double bond character. Total effective \(\pi\)-bonds: \[ =2 \] Lone pairs: On oxygen: \[ =2 \] On nitrogen: \[ =1 \] Total: \[ =3 \] Thus, \[ \boxed{9,\ 2,\ 3} \] Therefore, the correct answer is: \[ \boxed{(C)} \]
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