Aldehydes, Ketones and Carboxylic Acids NEET Previous Year Questions (PYQs)
Practice NEET previous year questions from Aldehydes, Ketones and Carboxylic Acids. These MCQs focus on reactions, mechanisms, acidity, nucleophilic addition and named reactions with answers and clear explanations.
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Aldehydes, Ketones & Carboxylic Acids Chapter Notes
Q1. Carboxylic acids have higher boiling points than aldehydes, ketones and even alcohols of comparable molecular mass due to:
(NEET 2018)
- (A) Intramolecular hydrogen bonding
- (B) Formation of carboxylate ion
- (C) Van der Waals forces
- (D) Intermolecular hydrogen bonding
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(D)
Show Explanation
Carboxylic acids form stable dimers through intermolecular hydrogen bonding.
Q2. A carbonyl compound having at least one α-hydrogen undergoes:
(NEET 2016)
- (A) Carbonylation
- (B) Aldehyde–ketone equilibration
- (C) Keto–enol tautomerism
- (D) Cannizzaro reaction
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(C)
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Presence of α-hydrogen allows interconversion between keto and enol forms.
Q3. The product formed when an aldehyde reacts with a primary amine is:
(NEET 2016)
- (A) Carboxylic acid
- (B) Ketone
- (C) Schiff’s base
- (D) Amide
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(C)
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Aldehydes react with primary amines to form imines (Schiff’s bases).
Q4. Which of the following does NOT give benzoic acid as the major product?
(NEET 2019)
- (A) Oxidation of toluene
- (B) Oxidation of benzaldehyde
- (C) Hydrolysis of benzoyl chloride
- (D) Hydrolysis of chlorobenzene
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(D)
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Chlorobenzene does not undergo hydrolysis under normal conditions.
Q5. The reaction in which aldehydes without α-hydrogen disproportionate is:
(NEET 2015)
- (A) Aldol reaction
- (B) Cannizzaro reaction
- (C) Perkin reaction
- (D) Claisen condensation
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(B)
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Aldehydes without α-hydrogen undergo Cannizzaro reaction in strong base.
Q6. Which reagent reduces aldehydes and ketones to hydrocarbons?
(NEET 2007)
- (A) NaBH4
- (B) LiAlH4
- (C) Zn–Hg / conc. HCl
- (D) PCC
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(C)
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Zn–Hg / conc. HCl performs Clemmensen reduction.
Q7. Which compound gives a positive Tollens’ test?
(NEET 1994)
- (A) Acetone
- (B) Acetic acid
- (C) Acetaldehyde
- (D) Acetamide
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(C)
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Aldehydes reduce Tollens’ reagent to silver mirror.
Q8. The oxidation of toluene to benzaldehyde using chromyl chloride is called:
(NEET 1996)
- (A) Etard reaction
- (B) Reimer–Tiemann reaction
- (C) Cannizzaro reaction
- (D) Friedel–Crafts reaction
Show Answer
(A)
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Chromyl chloride selectively oxidises methyl group to aldehyde.
Q9. Which compound gives iodoform test?
(NEET 1998)
- (A) Acetaldehyde
- (B) Ethanol
- (C) 2-Pentanone
- (D) 3-Pentanone
Show Answer
(D)
Show Explanation
Iodoform test requires –COCH3 group, absent in 3-pentanone.
Q10. Which compound is most reactive towards nucleophilic addition?
(NEET 2014)
- (A) Formaldehyde
- (B) Acetaldehyde
- (C) Acetone
- (D) Benzophenone
Show Answer
(A)
Show Explanation
Formaldehyde has no +I alkyl groups, making the carbonyl carbon most electrophilic.
Q11. The product of aldol condensation is:
(NEET 2007)
- (A) β-hydroxy aldehyde or ketone
- (B) α-hydroxy aldehyde
- (C) Unsaturated ester
- (D) Carboxylic acid
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(A)
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Aldol condensation forms β-hydroxy aldehydes or ketones.
Q12. Which acid is strongest?
(NEET 1988)
- (A) Acetic acid
- (B) Formic acid
- (C) Trichloroacetic acid
- (D) Propionic acid
Show Answer
(C)
Show Explanation
Strong –I effect of three Cl atoms increases acidity.
Q13. Which reaction does NOT form a C–C bond?
(NEET 2010)
- (A) Reimer–Tiemann
- (B) Cannizzaro
- (C) Wurtz
- (D) Friedel–Crafts acylation
Show Answer
(B)
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Cannizzaro reaction involves redox, not C–C bond formation.
Q14. Benzaldehyde reacts with acetophenone in dilute NaOH to give:
(NEET 2020)
- (A) Aldol product
- (B) Cross aldol product
- (C) Cannizzaro product
- (D) Ester
Show Answer
(B)
Show Explanation
This is a cross aldol condensation reaction.
Q15. Sodium bicarbonate distinguishes carboxylic acids from:
(NEET 1992)
- (A) Alcohols
- (B) Phenols
- (C) Aldehydes
- (D) Ketones
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(B)
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Carboxylic acids react with NaHCO3 releasing CO2, phenols do not.
Q16. Which compound undergoes Cannizzaro reaction?
(NEET 2003)
- (A) Acetaldehyde
- (B) Formaldehyde
- (C) Propanal
- (D) Acetone
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(B)
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Formaldehyde has no α-hydrogen.
Q17. Reduction of ester followed by hydrolysis gives:
(NEET 2000)
- (A) Two acids
- (B) Two alcohols
- (C) Acid + alcohol
- (D) Aldehyde + alcohol
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(B)
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LiAlH4 reduction of esters produces two alcohol molecules.
Q18. Self condensation of ethyl acetate in presence of sodium ethoxide gives:
(NEET 2006)
- (A) Ethyl butyrate
- (B) Acetoacetic ester
- (C) Ethyl propionate
- (D) Diethyl ether
Show Answer
(B)
Show Explanation
This is Claisen condensation.
Q19. Formalin is an aqueous solution of:
(NEET 1988)
- (A) Formic acid
- (B) Methanol
- (C) Formaldehyde
- (D) Furfural
Show Answer
(C)
Show Explanation
Formalin contains ~40% aqueous formaldehyde.
Q20. Which compound is oxidised to ketone?
(NEET 2004)
- (A) Primary alcohol
- (B) Secondary alcohol
- (C) Tertiary alcohol
- (D) Phenol
Show Answer
(B)
Show Explanation
Secondary alcohols oxidise to ketones.
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