Chemistry Carboxylic Acids MDCAT 2012
PMDC Verified Question 87 of 94
When ethanoyl chloride reacts with methylamine an amide is formed. What is the structure of the amide formed?
A
\( \text{CH}_3\text{-CH}_2\text{-C(=O)-NH}_2 \)
B
\( \text{CH}_3\text{-C(=O)-NH}_2 \)
C
\( \text{CH}_3\text{-CH}_2\text{-C(=O)-NHCH}_3 \)
D
\( \text{CH}_3\text{-C(=O)-NHCH}_3 \)
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option D: \( \text{CH}_3\text{-C(=O)-NHCH}_3 \)
Concept:

Acid chlorides react readily with primary amines via nucleophilic acyl substitution to form N-substituted amides.

Formula:

$$ \text{CH}_3\text{COCl} + \text{CH}_3\text{NH}_2 \longrightarrow \text{CH}_3\text{CONHCH}_3 + \text{HCl} $$

Solution:

  • Ethanoyl chloride provides the \( \text{CH}_3\text{CO-} \) (acetyl) group.


  • Methylamine provides the \( \text{-NHCH}_3 \) nucleophile.


  • The chlorine atom is expelled as a leaving group, resulting in N-methylethanamide (\( \text{CH}_3\text{-C(=O)-NHCH}_3 \)).


Why other options are incorrect:

Option A and C contain propanoyl groups instead of ethanoyl. Option B is formed if ammonia is used instead of methylamine.

Quality & Fidelity Assurance: Every question on BeambePrep is rigorously curated against the official PMDC syllabus with zero filler, zero out-of-syllabus content, and zero typos. When an authentic past paper originally contained a historical mistake or ambiguity from the examining board (such as UHS or NUMS), BeambePrep faithfully reflects the original paper while detailing the nuance and scientific consensus in the autopsy above.

Previous Question All Carboxylic Acids MCQs Next Question

Want to solve full-length papers under timed exam conditions?

Practice with zero-scroll lockdown sprints, dynamic latency zone timers, live peer selection telemetry, and the automated Amber mistake recovery loop.

Enter Arena Sprint iOS App Android App