MolSynapsequestion bank
MolSynapse / Question bank / Amines and Aromatic Nitrogen Compounds / Basicity of amines
JEE Advanced levelOne or more correct optionsDifficulty 3 of 3nc122

Which of the following statements are correct?

  1. AAcetanilide is a much weaker base than aniline because the nitrogen lone pair is also delocalised onto the carbonyl oxygen.
  2. BGuanidine is a very strong base because its conjugate acid is stabilised by resonance among three equivalent nitrogen atoms.
  3. CPyridine is more basic than pyrrole because the pyridine nitrogen lone pair lies in an sp2 orbital outside the aromatic sextet.
  4. DIn aqueous solution trimethylamine is the strongest base among the methylamines because it has three +I methyl groups.

Answer: A, B, C

In acetanilide the lone pair is shared with C=O in addition to the ring, so (A) is correct. The guanidinium ion has three equivalent resonance forms, (B) is correct. The pyrrole lone pair is part of the aromatic sextet whereas the pyridine lone pair is not, (C) is correct. In water trimethylamine is weaker than dimethylamine and methylamine because of poor solvation and steric hindrance, so (D) is wrong.
Practice Amines and Aromatic Nitrogen Compounds More on Basicity of amines
Previous questionNext question

More questions on Basicity of amines