Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
The reagent used to distinguish between acetaldehyde and benzaldehyde is
ChemistryAldehydes and KetonesJEE Main
Options:
  • A Tollen's reagent
  • B Fehling's solution
  • C 2-4-dinitrophenyl hydrazine
  • D semicarbazide
Solution:
1655 Upvotes Verified Answer
The correct answer is: Fehling's solution
(i) Reaction with 2,4-dinitrophenylhydrazine (Brady's reagent) : Acetaldehyde and benzaldehyde react with 2,4-dinitrophenylhydrazine (DNP) to form yellow, orange or red ppt of 2,4-dinitrophenylhydrazones (DNP derivatives)



(ii) Reaction with semicarbazide : Both acetaldehyde and benzaldehyde react with semicarbazide to form.


(iii) Reduction ot Tollen's reagent both acetaldehyde and benzaldehyde reduce Tollen's reagent to metallic silver which deposit on the walls of the test tube as bright silver mirror


(iv) Reduction of Fehling's solution: Acetaldehyde reduces Fehling solution to a red ppt of cuprous oxide.


However, benzaldehyde does not reduce Fehling's solution.

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.