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प्रश्न
Why is the α-hydrogens of aldehydes and ketones are acidic in nature?
Account for the following:
The alpha (α)-hydrogens of aldehydes and ketones are acidic in nature.
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उत्तर
Because of the strong electron-withdrawing nature of the carbonyl groups and the resonance stabilisation of the conjugate base, aldehydes and ketones are acidic in nature.

| \[\begin{array}{cc} \ce{R}\phantom{..........}\\ \backslash\phantom{........}\\ \ce{C = O}\\ /\phantom{........}\\ \ce{H}\phantom{..........}\\ \end{array}\] |
\[\begin{array}{cc} \ce{R}\phantom{..........}\\ \backslash\phantom{........}\\ \ce{C = O}\\ /\phantom{........}\\ \ce{R}\phantom{..........}\\ \end{array}\] |
| Aldehyde | Ketone |
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संबंधित प्रश्न
How will you bring about the following conversion in not more than two steps?
Ethanol to 3-Hydroxybutanal
Which product is formed when the compound
is treated with concentrated aqueous \[\ce{KOH}\] solution?
Compound ‘A’ was prepared by oxidation of compound ‘B’ with alkaline \[\ce{KMnO4}\]. Compound ‘A’ on reduction with lithium aluminium hydride gets converted back to compound ‘B’. When compound ‘A’ is heated with compound B in the presence of \[\ce{H2SO4}\] it produces fruity smell of compound C to which family the compounds ‘A’, ‘B’ and ‘C’ belong to?
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.
Give reasons to support the answer:
Presence of Alpha hydrogen in aldehydes and ketones is essential for aldol condensation.
Which of the following gives aldol con~ensation reaction?
Identify A and B from the following reaction:
\[\begin{array}{cc}
\ce{CH3}\phantom{.................}\\
|\phantom{....................}\\
\phantom{}\ce{2CH3 - C = O ->[Ba(OH)2] A ->[Δ] B + H2O}
\end{array}\]
Which of the following compounds will undergo self-condensation in the presence of dilute NaOH solution?

Identify A and B:
Which one of the following undergoes reaction with 50% sodiumhydroxide solution to give the corresponding alcohol and acid:
