KCET · Chemistry · Aldehydes and Ketones
The reagent used to distinguish between acetaldehyde and benzaldehyde is
- A Tollen's reagent
- B Fehling's solution
- C 2-4-dinitrophenyl hydrazine
- D semicarbazide
Answer & Solution
Correct Answer
(B) Fehling's solution
Step-by-step Solution
Detailed explanation
(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.

(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.
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Chemistry
- In a face centred cubic arrangement of \( A \) and \( B \) atoms in which 'A' atoms are at the corners of
the unit cell and 'B' atoms are at the face centers. One of the 'A' atom is missing from one
corner in unit cell.the simplest formula of the compound isKCET 2017 Easy - The major product of the following reaction is \(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{CH}_{2}-\mathrm{OH} \underset{\text { Excess }}{\stackrel{\mathrm{HBr}}{\longrightarrow}}\) ProductKCET 2021 Medium
- The electronic conductance depends onKCET 2025 Easy
- Silver iodide is used for producing artificial rain because AglKCET 2012 Easy
- Excess of silver nitrate solution is added to \(100 \mathrm{~mL}\) of \(0.01 \mathrm{M}\) pentaaqua chloro chromium (III) chloride solution. The mass of silver chloride obtained in grams is [Atomic mass of silver is 108].KCET 2011 Medium
- Give the IUPAC name of \(\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4}\right]\left[\mathrm{Pt} \mathrm{Cl}_{4}\right]\) isKCET 2020 Easy
More PYQs from KCET
- Which of the following is not a characteristic of a covalent compound?KCET 2012 Medium
- In malignant tumours, the cell divide rapidly and move to distant parts of the body and cause new tumours. This property is called.KCET 2018 Easy
- A body of mass \( 50 \mathrm{~kg} \), is suspended using a spring balance inside a lift at rest. If the lift starts
falling freely, the reading of the spring balance isKCET 2017 Easy - Resonance effect is not observed inKCET 2019 Easy
- Which of the following hormones does not contain a polypeptide?KCET 2009 Hard
- If \(A\) and \(B\) are square matrices of the same order such that \((A+B)(A-B)=A^{2}-B^{2}\), then \(\left(A B A^{-1}\right)^{2}\) is equal toKCET 2009 Easy