Chemistry · Aldehydes and Ketones
JEE Main 2024 — 4 April, Shift 1 — Question 67
Given below are two statements, one is labelled as Statement I and the other is labelled as Statement II.
Statement I : Acidity of -hydrogens of aldehydes and ketones is responsible for Aldol reaction.
Statement II : Reaction between benzaldehyde and ethanal will NOT give Cross - Aldol product.
In the light of above statements, choose the most appropriate answer from the options given below:
- Option A:
Both statement I and statement Il are correct.
- Option B:Correct
Statement I is correct and statement Il is incorrect.
- Option C:
Statement I is incorrect and statement Il is correct.
- Option D:
Both statements I and statements ll are incorrect.
Answer: B
Step-by-step solution
Statement I is Correct: The Aldol reaction occurs due to the presence of acidic -hydrogens in aldehydes and ketones. These -hydrogens are removed to form an enolate ion, which then attacks the carbonyl carbon of another molecule, initiating the aldol reaction.
Statement II is Incorrect: Benzaldehyde does not have -hydrogens, but ethanal does. Therefore, ethanal can form an enolate ion and react with benzaldehyde to give a cross-aldol product. Hence, the statement saying that the reaction will not give a cross-aldol product is incorrect.
Thus, Statement I is correct and Statement II is incorrect (Option B).
Answer key and solution verified before publishing.
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- Exam
- JEE Main 2024
- Paper
- 4 April, Shift 1
- Subject
- Chemistry
- Chapter
- Aldehydes and Ketones
- Topic
- Chemical properties of Aldehydes & Ketones