Which of the following statements are correct?
A. p-Nitroaniline is a stronger base than aniline
B. Aniline is a weaker base than o-nitroaniline
C. Aniline is a weaker base than ethylamine
D. p-methoxyaniline is stronger base than aniline
E. Aniline is weaker base than ammonia
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → E, C and D only
The basic strength of an amine depends on how freely the lone pair on nitrogen is available for a proton. In aniline the lone pair is delocalised into the benzene ring, so aniline is weaker than ammonia and than alkylamines. On the ring, electron-releasing groups increase the basic strength and electron-withdrawing groups decrease it.
(A) p-Nitroaniline is a stronger base than aniline — False. –\( \ce{NO2} \) withdraws electrons, so p-nitroaniline is weaker.
(B) Aniline is a weaker base than o-nitroaniline — False. o-Nitroaniline is weaker still; the nitro group pulls the lone pair further away.
(C) Aniline is a weaker base than ethylamine — True. The ethyl group pushes electrons (+I) towards nitrogen, while in aniline the lone pair is delocalised.
(D) p-methoxyaniline is stronger base than aniline — True. –\( \ce{OCH3} \) at the para position releases electrons and raises the basic strength.
(E) Aniline is weaker base than ammonia — True. Resonance makes aniline more stable than the anilinium ion, lowering its proton acceptability.
NCERT (2026-27 edition):
Arylamines versus Ammonia – …
