The blue color of Fehling solution is changed to red when warmed with an aldehyde due to the formation of which of the following?
Correct answer: B. Cu2O
- A. CO2
- B. Cu2O
- C. AgO
- D. SO2
Explanation
The blue color of Fehling's solution changes to red when warmed with an aldehyde due to the formation of Cu₂O (copper(I) oxide) because of the reduction of Cu²⁺ ions present in the solution.
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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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