Aldehydes are more reactive than ketones because they have:
Correct answer: B. Less steric hindrance
- A. More electron donating groups
- B. Less steric hindrance
- C. Both A and B
- D. None of these
Explanation
The reactivity difference between aldehydes and ketones is mainly due to steric hindrance. In aldehydes, the carbonyl group is always at the end of the carbon chain, and there is an additional hydrogen atom attached to the carbonyl carbon. On the other hand, ketones have the carbonyl group in the middle of the carbon chain, with two carbon groups (alkyl or aryl groups) attached to the carbonyl carbon. The presence of these additional carbon groups in ketones leads to more steric hindrance compared to aldehydes. Steric hindrance makes it more difficult for nucleophiles to approach the electrophilic carbonyl carbon, thus reducing the reactivity of ketones compared to aldehydes. Therefore, option b is correct.
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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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