Carbonyl Compounds MCQs [Organic Chemistry]

By: Prof. Dr. Fazal Rehman | Last updated: February 3, 2024

MCQs-based questions and answers on Carbonyl Compounds in organic chemistry.

Which reagent will react with both aldehyde and ketone?

1. Grignard reagent
2. Sodium nitroprusside
3. Fehling’s reagent
4. Tollen’s reagent

Question’s Answer: Sodium nitroprusside

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Acetone can be converted into pinacol by

1. Na/Hg
2. Zn/Hg
3. Mg/Hg
4. All of these

Question’s Answer: Mg/Hg

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Which compounds will not give iodoform test on treatment with I₂/NaOH?

1. 2-Butanone
2. 3-Pentanone
3. Acetone
4. Acetaldehyde

Question’s Answer: 2-Butanone

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Crabonyl compounds react hydroxylamine to form  ___________ .

1. Hyrazone
2. Cyanohydrin
3. Oxime
4. None of these

Question’s Answer: Oxime

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Which test is not given by aldehyde?

A Sodium nitroprusside test

1. Fehling solution test
2. 2.4-DNP test
3. NaHSO₃ test

Question’s Answer: Sodium nitroprusside test

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Paraldehyde is helpful and used as_________.

1. Poison
2. Dye
3. Polymer
4. Medicine

Question’s Answer: Medicine

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The correct order of reactivity of CH₃CHO, C₂H₃COCH, and CH₃COCH₃ is

1. CH₃COCH > CH3CHO> C₂H₅COCH₃
2. C₂H₃COCH > CH3COCH₃ > CH3CHO
3. CH₃CHO > CH3COCH₃ > CH₃COC₂H₅
4. CH₃COCH₃ > C₂H₅COCH₃ > CH₃CHO

Question’s Answer: CH₃CHO > CH3COCH₃ > CH₃COC₂H₅

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Which has most acidic hydrogen?

1. hexanone
2. 2,3-hexanedione
3. 2,5-hexanedione
4. Hexanedione

Question’s Answer: Hexanedione

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Industrial production of acetaldehyde is done by

1. Oxidation of ethanol
2. Oxidation of ethylene in the presence of
3. Reduction of acetic acid
4. Hydration of acetylene

Question’s Answer: Oxidation of ethylene in the presence of

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In Which compounds, carbon number is decreased during oxidation

1. Formaldehydec
2. Aldehyde
3. Ketone
4. Ethanol

Question’s Answer: Ketone

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Which will not show haloform reaction?

1. CH₃CHO
2. C₆H₅CHO
3. CH₃COCH₃
4. C₆H₅COCH₃

Question’s Answer: C₆H₅CHO

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What is a mixed ketone?

1. Acetone
2. Diethyl ketone
3. Benzophenone
4. Acetophenone

Question’s Answer: Acetophenone

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Which aldehydes is most reactive?

1. HCHO
2. CH₃CHO
3. C₂H₅CHO
4. C₆H₅CHO

Question’s Answer: HCHO

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The condensation between formaldehyde and acetaldehyde in the presence of conc. NaOH and heat gives

1. Mixture of CH₃CH₂OH and HCOO^–Na⁺
2. Mixture of CH₃OH and CH₃COO^–Na⁺
3. Acrolein
4. None of these

Question’s Answer: Acrolein

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The reagent which can be helpful and used to distinguish acetophenone from benzophenone is

1. 2,4-dinito phenyl hydrazine
2. I₂ and NaOH
3. Benedict reagent
4. LIAIH₄

Question’s Answer: I₂ and NaOH

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Ketones are prepared by the oxidation of

1. 1° Alcohol
2. 3° Alcohol
3. 2° Alcohol
4. None of these

Question’s Answer: 2° Alcohol

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When a formaldehyde solution is evaporated to dryness, a white crystalline solid is obtained. This is known as

1. Formose
2. Hexa methylene tetramine
3. Trioxy methylene
4. Para formaldehyde

Question’s Answer: Para formaldehyde

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Which does not give Cannizzaro’s reaction?

1. Benzophenone
2. Benzaldehyde
3. Acetaldehyde
4. Formaldehyde

Question’s Answer: Acetaldehyde

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The C-atom in aldehyde and ketone is _________ hybridized

1. sp³
2. sp
3. dsp
4. sp²

Question’s Answer: sp²

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Which is least reactive?

1. C₂H₃CHO

B C₆H₅CHO

1. CH₃CHO
2. HCHO

Question’s Answer: C₆H₅CHO

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Schiff’s reagent gives pink color with ________.

1. Acetic acid
2. Acetone
3. Acetaldehyde
4. Methyl acetate

Question’s Answer: Acetaldehyde

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Which tests issued to distinguish between aldehyde and ketone?

1. Fehling solution test
2. Schiff reagent test
3. Tollen’s reagent test
4. Sodium nitroprusside test

Question’s Answer: Sodium nitroprusside test

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Which will undergo nucleophilic addition reaction more easily?

1. Amines
2. Aldehyde
3. Ketone
4. Alkene

Question’s Answer: Aldehyde

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Aldol consists of

1. Hydroxyl group
2. Aldehyde group
3. Carboxylic group
4. Both A and B

Question’s Answer: Hydroxyl group

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Calcium formate on dry distillation yields

1. Formaldehyde
2. Acetaldehyde
3. Formic acid
4. Ketone

Question’s Answer: Ketone

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Which reactions is not given by acetone?

1. Iodoform reaction
2. Reduction of Fehling’s solution
3. Formation of an addition compound with sodium hydrogen sulfite
4. Formation of crystals with 2,4-dinitrophenyl hydrazine

Question’s Answer: Reduction of Fehling’s solution

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Which is the strongest reducing agent?

1. C₃H₇OH
2. CH₃COCH₃
3. HCHO
4. C₂H₅OH

Question’s Answer: HCHO

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What will happened, hen aldehyde reacts with Tollen’s reagent?

1. A ketone is formed
2. An alcohol is formed
3. Ag^– ions are reduced
4. Ag⁺ ions are produced

Question’s Answer: Ag^– ions are reduced

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The red brown ppt of Fehling solution and Benedict solution tests are of ______.

1. AgBr
2. Cu₂O
3. Cuo
4. Ag

Question’s Answer: Cu₂O

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Ketone on reduction produces which of the following?

1. Secondary alcohol
2. Primary alcohol
3. Tertiary alcohol

D Acetic acid

Question’s Answer: Secondary alcohol

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Which statements regarding carbonyl group is not correct?

1. The aryl group in aromatic aldehydes speeds up the addition reaction across the carbonyl group
2. The carbon atom of carbonyl group in the transition state formed during the addition reaction across the carbonyl group is sp³ hybridized
3. The carbon atom of carbonyl group in aldehydes is sp² hybridized
4. An aryl group stabilizes the aldehyde more than the transition state

Question’s Answer: The aryl group in aromatic aldehydes speeds up the addition reaction across the carbonyl group

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Reactivity of carbonyl compounds is

1. Electrophilic carbon
2. Unsaturation
3. Less steric hindrance
4. All of these

Question’s Answer: All of these

More Organic chemistry MCQs

1. Organic chemistry MCQs
2. Active Methylene Compounds MCQs
3. Alcohols and Phenols MCQs
4. Carbonyl Compounds MCQs
5. Halogenated Organic Compounds MCQs
6. Carboxylic Acids MCQs
7. Hydrocarbons MCQs
8. Nitrogen-Containing Organic Compounds MCQs
9. Polymers MCQs
10. Nomenclature of Organic Compounds MCQs
11. Organic Acids and Bases MCQs
12. Organic Spectroscopy MCQs
13. Purification and Characterization of Organic Compounds MCQs
14. Reaction Mechanism MCQs
15. Stereochemistry MCQs
16. Organic Molecules MCQs
17. CHEMISTRY MCQs From all subjects of  Chemistry

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