Which of the following statement/s is/are wrong?
A. Methylamine is more basic than ammonia.
B. Amines form hydrogen bond.
C. Ethylamine has higher boiling point than propane.
D. Dimethylamine is less basic than methylamine.
E. Amines are soluble in organic solvents like alcohol.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → D only
A. Methylamine is more basic than ammonia — Correct. The electron-releasing (+I) methyl group increases the electron density on nitrogen, so \( \ce{CH3NH2} \) is a stronger base than \( \ce{NH3} \).
B. Amines form hydrogen bond — Correct. Primary and secondary amines have N–H bonds and form intermolecular hydrogen bonds; all amines form hydrogen bonds with water.
C. Ethylamine has higher boiling point than propane — Correct. Ethylamine (molar mass 45) is hydrogen bonded, while propane (molar mass 44) has only weak van der Waals forces.
D. Dimethylamine is less basic than methylamine — Incorrect. In aqueous solution the order of basic strength is \( \ce{(CH3)2NH} \) > \( \ce{CH3NH2} \) > \( \ce{(CH3)3N} \) > \( \ce{NH3} \); two methyl groups give a larger +I effect, and the ion is still well solvated. So dimethylamine is more basic than methylamine.
E. Amines are soluble in organic solvents like alcohol — Correct. Amines dissolve in organic solvents such as alcohol, ether and benzene.
NCERT (2026-27 edition):
Basic Character of Amines – “… The order of basic strength in case of methyl substituted amines and ethyl substituted amines in aqueous solution is as follows: (C2H5)2NH > (C2H5)3N > C2H5NH2 > NH3; (CH3)2NH > CH3NH2 > (CH3)3N > NH3”