Answer the question on the basis of passage given below:
There are three kinds of amines which are primary, secondary and tertiary amines. These amines may have alkyl group or aryl group or both alkyl and aryl groups. These amines can be distinguished from one another by various chemical tests.
Which of the following amines when treated with chloroform and \(KOH\) give foul smelling substance. \(A\) is:
A. Primary amine
B. Secondary amine
C. Tertiary amine
D. Aniline
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → A and D
The carbylamine reaction is a test for primary amines, aliphatic and aromatic: on heating with chloroform and ethanolic KOH they form isocyanides (carbylamines), which are foul smelling.
\( \ce{R-NH2 + CHCl3 + 3KOH} \xrightarrow{\ce{\Delta}} \ce{R-NC + 3KCl + 3H2O} \)
(A) Primary amine — Correct. It has two H atoms on nitrogen and gives an alkyl isocyanide.
(B) Secondary amine — Incorrect. Secondary amines do not show the carbylamine reaction.
(C) Tertiary amine — Incorrect. Tertiary amines have no H on nitrogen and do not react.
(D) Aniline — Correct. Aniline is a primary aromatic amine and gives phenyl isocyanide.
\( \ce{C6H5NH2 + CHCl3 + 3KOH} \xrightarrow{\ce{\Delta}} \ce{C6H5NC + 3KCl + 3H2O} \)
NCERT (2026-27 edition):
Chemical Reactions – …
