AIIMS 2017 Chemistry Reactivity of Carbonyl Compounds Assertion Reason Question
Assertion (A): Benzaldehyde is more reactive than ethanal towards nucleophilic attack.
Reason (R): The overall effect of and effect of phenyl group decreases the electron density on the carbon atom of the carbonyl group in benzaldehyde.
Both Assertion and Reason are true and Reason is the correct explanation of Assertion
Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
Assertion is true but Reason is false
Both Assertion and Reason are false
Correct Answer
Detailed Explanation
Option A is correct because benzaldehyde is indeed more reactive than ethanol towards nucleophilic attack due to the electron-withdrawing inductive effect (–I) of the phenyl group, which decreases the electron density on the carbonyl carbon (>C=O). This makes the carbonyl carbon more electrophilic and susceptible to nucleophilic attack. Other options are incorrect because option B suggests that the reason does not explain the assertion, while options C and D incorrectly state that either the assertion or the reason is false, which contradicts the established reactivity of benzaldehyde compared to ethanol. Understanding the influence of resonance (+R) and inductive effects (–I) on carbonyl reactivity is crucial in organic chemistry.
Found an issue with this question?