Answer: tertiary.
- A primary
- B tertiary
- C quaternary
- D secondary
Correct answer: B. tertiary
Explanation: All three hydrogens of ammonia are replaced by alkyl groups, so it is a tertiary amine.
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.