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Karnataka Board PUCPUC Science 2nd PUC Class 12

Assertion: The α-hydrogen atom in carbonyl compounds is less acidic. Reason: The anion formed after the loss of α-hydrogen atom is resonance stabilised.

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Question

Assertion: The α-hydrogen atom in carbonyl compounds is less acidic.

Reason: The anion formed after the loss of α-hydrogen atom is resonance stabilised.

Options

  • Assertion and reason both are correct and reason is correct explanation of assertion.

  • Assertion and reason both are wrong statements.

  • Assertion is correct statement but reason is wrong statement.

  • Assertion is wrong statement but reason is correct statement.

  • Assertion and reason both are correct statements but reasson is not correct explanation of assertion.

MCQ
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Solution

Assertion is wrong statement but reason is correct statement.

Explanation:

Because of the presence of electron-withdrawing carbonyl group, the alpha hydrogen atom in carbonyl compounds is acidic. In nature, hydrogen is very acidic.

Because the cation is released in the form of \[\ce{H-}\], the anion created after the loss of the -hydrogen atom is resonance stabilised. 

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Chapter 12: Aldehydes, Ketones and Carboxylic Acids - Multiple Choice Questions (Type - I) [Page 176]

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NCERT Exemplar Chemistry Exemplar [English] Class 12
Chapter 12 Aldehydes, Ketones and Carboxylic Acids
Multiple Choice Questions (Type - I) | Q 44 | Page 176

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