Concept:Aldehydes have a hydrogen atom attached to the carbonyl carbon, making them easily oxidizable. Ketones lack this hydrogen and are very difficult to oxidize.
Solution:- Fehling's solution is a mild oxidizing agent (containing complexed Copper(II) ions).
- When an aldehyde is heated with Fehling's solution, it is oxidized, and the copper is reduced to form a brick-red precipitate of Copper(I) oxide.
- Ketones do not react with Fehling's solution, making it a perfect discriminatory test.
Why other options are incorrect:Strong oxidizing agents like \( K_2Cr_2O_7 \) under harsh conditions can sometimes cleave and oxidize ketones too, making it a poorer choice for simple qualitative discrimination compared to mild, specific reagents like Fehling's or Tollens'.
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