Chemistry Aldehydes & Ketones ETEA 2023
PMDC Verified Question 21 of 94
Fehling's solution works on the principle of redox reaction which results in:
A
Reduction of Aldehydes
B
Oxidation of Copper
C
Oxidation of Aldehyde
D
Oxidation of ketone
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option C: Oxidation of Aldehyde
Concept:

Fehling's solution is a mild chemical test based on simultaneous oxidation and reduction.

Solution:

  • Fehling's solution contains Copper(II) ions, which act as the oxidizing agent.


  • When an aldehyde is introduced, the aldehyde provides electrons to the copper.


  • As a result, the copper is reduced (from \( Cu^{+2} \) to \( Cu^{+1} \)).


  • Simultaneously, the aldehyde loses these electrons and is transformed into a carboxylate salt. This means the overall transformative result for the organic molecule is the Oxidation of the Aldehyde.


Why other options are incorrect:

Aldehydes are oxidized, not reduced (Option A). Copper is reduced, not oxidized (Option B). Ketones resist this reaction entirely and are not oxidized (Option D).

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