Question

The correct order of the increasing basicity of methyl amine, ammonia and aniline is

• A. methyl amine < aniline < ammonia
• B. aniline < ammonia < methyl amine
• C. aniline < methyl amine < ammonia
• D. ammonia < aniline < methyl amine

Answer 1

Answer: (B)

aniline < ammonia < methyl amine

Answer 2

In aniline the lone pair on N is involved in delocalization with benzene ring and is not available for protonation. Methyl amine is a stronger base than ammonia because +I effect of methyl group increases electron density on N making it more basic than ${NH_3}$. Cannot be protonated. least basic {\underset{\text{ +I Effect increases basicity. }}{ { CH_2 -> - NH_2}}}