Exams › JEE Advanced › Chemistry

Consider the following two statements about aniline and acetamide: Statement I: Aniline is less basic than acetamide. Statement II: In aniline, the lone pair on nitrogen is delocalized into the benzene ring through resonance and is therefore less available for protonation. Choose the correct option.

1. Statement I is true but statement II is false.
2. Statement I is false but statement II is true.
3. Both statement I and statement II are true.
4. Both statement I and statement II are false.

Correct answer: Statement I is false but statement II is true.

Solution

Acetamide is less basic than aniline because in acetamide the nitrogen lone pair is strongly delocalized into the C=O pi system (more effective withdrawal), making it far less available for protonation (pKb ~ 14 for acetamide vs pKb ~ 9.4 for aniline). So aniline is MORE basic than acetamide, making Statement I false. Statement II correctly explains the resonance delocalization in aniline, so Statement II is true.

Related JEE Advanced Chemistry questions

• The transformation of C2H5CON to C2H5NCO demonstrates a rearrangement involving the migration of an alkyl group to which site?
• The hyperconjugative stabilities of tert-butyl cation and 2-butene, respectively, are due to -
• How many valid pairs (P1, P2) are possible such that 'P1-methylpent-P2-yne' is a correct IUPAC name, where P1 denotes the position of the methyl substituent and P2 denotes the position of the triple bond?
• In the Reimer-Tiemann reaction (phenol + CHCl3 + NaOH, heated), which intermediate is formed on the pathway to salicylaldehyde?
• How many of the following groups show a negative inductive (-I) effect? (a) -Cl (b) -CH3 (c) -O(-) (d) -COO(-) (e) -CMe3 (f) -F (g) -NH2 (h) -OH (i) -NO2 (j) -N=O (k) (+)-NH3
• How many of the following compounds are more acidic than ethanol (CH3-CH2-OH)? (a) CF3-CH2-OH (2,2,2-trifluoroethanol) (b) CH3-CF2-OH (1,1-difluoroethanol) (c) CH3-C(=O)-OH (acetic acid) (d) CH3-CH(OH)-CH3 (propan-2-ol)

⚔️ Practice JEE Advanced Chemistry free + battle 1v1 →