Answer: Soluble sulfonamide salt.
- A Soluble sulfonamide salt
- B Insoluble sulfonamide
- C No reaction
- D Diazonium salt
Correct answer: A. Soluble sulfonamide salt
Explanation: Primary aromatic amines give a sulfonamide that dissolves in NaOH (has one acidic H on N).
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.