Answer: Primary amine.
- A Primary amine
- B Secondary amine
- C Tertiary amine
- D Quaternary ammonium salt
Correct answer: A. Primary amine
Explanation: Only primary amines give the characteristic foul-smelling isocyanide in the carbylamine test.
In aniline, the nitrogen's lone pair is pulled into the benzene ring through resonance, leaving less electron density available to accept a proton - which is why aniline is a much weaker base than methylamine, where the lone pair is fully available.
Concept context
Nitrogen-containing organic compounds. Covers classification (primary, secondary, tertiary), basicity comparison, preparation methods, and reactions including diazotization and coupling, key for understanding dyes and pharmaceuticals.