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Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.
Assertion (A): Benzaldehyde is less reactive than ethanal towards nucleophilic addition reactions.
Reason (R): Ethanal is more sterically hindered.
  • a)
    Both A and R are true and R is the correct explanation of A
  • b)
    Both A and R are true but R is NOT the correct explanation of A
  • c)
    A is true but R is false
  • d)
    A is false and R is true
Correct answer is option 'B'. Can you explain this answer?
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Directions: In the following questions, A statement of Assertion (A) ...
The carbon atom of the carbonyl group of benzaldehyde is less electrophilic than carbon atom of carbonyl group present in ethanal. The polarity of the carbonyl group is reduced in benzaldehyde due to resonance hence it is less reactive than ethanal towards nucleophilic addition reaction.
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Directions: In the following questions, A statement of Assertion (A) ...
Assertion (A): Benzaldehyde is less reactive than ethanal towards nucleophilic addition reactions.
Reason (R): Ethanal is more sterically hindered.

The correct answer is option 'B' - Both A and R are true but R is NOT the correct explanation of A.

Explanation:
Nucleophilic addition reactions involve the addition of a nucleophile to a carbonyl group, resulting in the formation of a new bond. In this case, we are comparing the reactivity of benzaldehyde and ethanal towards nucleophilic addition reactions.

Reactivity of Benzaldehyde:
Benzaldehyde has a phenyl group attached to the carbonyl carbon. The presence of the phenyl group in benzaldehyde makes the carbonyl carbon less electrophilic compared to that in ethanal. This is because the phenyl group is electron-donating and destabilizes the partial positive charge on the carbonyl carbon. Therefore, benzaldehyde is less reactive towards nucleophilic addition reactions compared to ethanal.

Reactivity of Ethanal:
Ethanal does not have any bulky substituents attached to the carbonyl carbon. Therefore, the carbonyl carbon in ethanal is more electrophilic compared to that in benzaldehyde. This makes ethanal more reactive towards nucleophilic addition reactions.

Steric Hindrance:
The reason provided in the statement (R) is that ethanal is more sterically hindered. Steric hindrance refers to the obstruction of a reaction due to the presence of bulky substituents. However, this reason is not correct in this context. Ethanal is actually less sterically hindered compared to benzaldehyde because it does not have any bulky substituents. Therefore, the reason provided is not the correct explanation for the difference in reactivity between benzaldehyde and ethanal.

In conclusion, both the assertion and reason are true, but the reason is not the correct explanation for the assertion. Hence, the correct answer is option 'B' - Both A and R are true but R is NOT the correct explanation of A.
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Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.Assertion (A): Benzaldehyde is less reactive than ethanal towards nucleophilic addition reactions.Reason (R): Ethanal is more sterically hindered.a)Both A and R are true and R is the correct explanation of Ab)Both A and R are true but R is NOT the correct explanation of Ac)A is true but R is falsed)A is false and R is trueCorrect answer is option 'B'. Can you explain this answer?
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Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.Assertion (A): Benzaldehyde is less reactive than ethanal towards nucleophilic addition reactions.Reason (R): Ethanal is more sterically hindered.a)Both A and R are true and R is the correct explanation of Ab)Both A and R are true but R is NOT the correct explanation of Ac)A is true but R is falsed)A is false and R is trueCorrect answer is option 'B'. Can you explain this answer? for Class 12 2024 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.Assertion (A): Benzaldehyde is less reactive than ethanal towards nucleophilic addition reactions.Reason (R): Ethanal is more sterically hindered.a)Both A and R are true and R is the correct explanation of Ab)Both A and R are true but R is NOT the correct explanation of Ac)A is true but R is falsed)A is false and R is trueCorrect answer is option 'B'. Can you explain this answer? covers all topics & solutions for Class 12 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.Assertion (A): Benzaldehyde is less reactive than ethanal towards nucleophilic addition reactions.Reason (R): Ethanal is more sterically hindered.a)Both A and R are true and R is the correct explanation of Ab)Both A and R are true but R is NOT the correct explanation of Ac)A is true but R is falsed)A is false and R is trueCorrect answer is option 'B'. Can you explain this answer?.
Solutions for Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.Assertion (A): Benzaldehyde is less reactive than ethanal towards nucleophilic addition reactions.Reason (R): Ethanal is more sterically hindered.a)Both A and R are true and R is the correct explanation of Ab)Both A and R are true but R is NOT the correct explanation of Ac)A is true but R is falsed)A is false and R is trueCorrect answer is option 'B'. Can you explain this answer? in English & in Hindi are available as part of our courses for Class 12. Download more important topics, notes, lectures and mock test series for Class 12 Exam by signing up for free.
Here you can find the meaning of Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.Assertion (A): Benzaldehyde is less reactive than ethanal towards nucleophilic addition reactions.Reason (R): Ethanal is more sterically hindered.a)Both A and R are true and R is the correct explanation of Ab)Both A and R are true but R is NOT the correct explanation of Ac)A is true but R is falsed)A is false and R is trueCorrect answer is option 'B'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.Assertion (A): Benzaldehyde is less reactive than ethanal towards nucleophilic addition reactions.Reason (R): Ethanal is more sterically hindered.a)Both A and R are true and R is the correct explanation of Ab)Both A and R are true but R is NOT the correct explanation of Ac)A is true but R is falsed)A is false and R is trueCorrect answer is option 'B'. Can you explain this answer?, a detailed solution for Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.Assertion (A): Benzaldehyde is less reactive than ethanal towards nucleophilic addition reactions.Reason (R): Ethanal is more sterically hindered.a)Both A and R are true and R is the correct explanation of Ab)Both A and R are true but R is NOT the correct explanation of Ac)A is true but R is falsed)A is false and R is trueCorrect answer is option 'B'. Can you explain this answer? has been provided alongside types of Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.Assertion (A): Benzaldehyde is less reactive than ethanal towards nucleophilic addition reactions.Reason (R): Ethanal is more sterically hindered.a)Both A and R are true and R is the correct explanation of Ab)Both A and R are true but R is NOT the correct explanation of Ac)A is true but R is falsed)A is false and R is trueCorrect answer is option 'B'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.Assertion (A): Benzaldehyde is less reactive than ethanal towards nucleophilic addition reactions.Reason (R): Ethanal is more sterically hindered.a)Both A and R are true and R is the correct explanation of Ab)Both A and R are true but R is NOT the correct explanation of Ac)A is true but R is falsed)A is false and R is trueCorrect answer is option 'B'. Can you explain this answer? tests, examples and also practice Class 12 tests.
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