Which of the following is used as a test for aliphatic and aromatic primary amines?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Carbylamine test
A primary amine gives a foul-smelling isocyanide:
\( \displaystyle \ce{R-NH2 + CHCl3 + 3KOH} \xrightarrow{\text{Heat}} \ce{R-NC + 3KCl + 3H2O} \)
NCERT (2026-27 edition):
9.6 Chemical Reactions – “4. Carbylamine reaction
Aliphatic and aromatic primary amines on heating with chloroform and ethanolic potassium hydroxide form isocyanides or carbylamines which are foul smelling substances. Secondary and tertiary amines do not show this reaction. This reaction is known as carbylamine reaction or isocyanide test and is used as a test for primary amines.”