Chemistry Aldehydes & Ketones NUMS 2019
PMDC Verified Question 57 of 94
Carbonyl group undergo:
A
Electrophilic addition reaction
B
Nucleophilic addition reaction
C
Electrophilic substitution reaction
D
Nucleophilic substitution reaction
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option B: Nucleophilic addition reaction
Concept:

The reactivity of a functional group is dictated by its polarization. The carbonyl group (\( C=O \)) has a highly polarized double bond.

Solution:

  • Due to oxygen's higher electronegativity, the carbonyl carbon bears a partial positive charge (\( \delta^+ \)), making it an electrophilic center.


  • Nucleophiles (electron-rich species) are attracted to this carbon and attack it, breaking the \( \pi \) bond.


  • Since two molecules combine into one without losing any atoms, it is an addition reaction.


  • Therefore, the characteristic reaction is a Nucleophilic addition reaction.


Why other options are incorrect:

Electrophilic addition is typical of alkenes (\( C=C \)). Substitution reactions require a good leaving group, which aldehydes and ketones lack (unlike acyl chlorides or esters).

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