Acetal on acid hydrolysis generates
Correct answer: C. Both a & b
- A. Alcohol
- B. Ketone
- C. Both a & b
- D. None of the above
Explanation
Acetal, also known as 1,1-diethoxyethane (CH₃CH₂OCH₂CH₃), undergoes acid hydrolysis in the presence of strong acids like H₂SO₄ or HCl. This reaction follows two pathways, leading to a mixture of products:1. Cleavage of the acetal linkage: The acid protonates the oxygen atom in the acetal group, weakening the O-C bond and leading to its cleavage. This generates two molecules of ethanol (CH₃CH₂OH):CH₃CH₂OCH₂CH₃ + H₂O + H⁺ → 2 CH₃CH₂OH + H₂⁺2. Depolymerization to aldehyde: In a competing reaction, the acetal can undergo further protonation and rearrangement, ultimately breaking down into two molecules of acetaldehyde (CH₃CHO):CH₃CH₂OCH₂CH₃ + 2 H₂O + 2 H⁺ → 2 CH₃CHO + 2 CH₃CH₂OH + H₂⁺Therefore, acid hydrolysis of acetal yields a mixture of ethanol and acetaldehyde, making (c) Both a & b the accurate answer.
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About Aldehydes and Ketones
Aldehydes and ketones contain the polar carbonyl group, but aldehydes are generally more readily oxidised and more reactive than ketones. Coverage includes preparation by oxidation or reduction routes, nucleophilic addition of reagents such as hydrogen cyanide and bisulfite, and tests that distinguish aldehydes from ketones.
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