JEE Chemistry Aldehydes Ketones and Carboxylic Acids MCQs Set B

Question: Which of the following products is formed when benzaldehyde is treated with CH3MgBr and the addition product so obtained is subjected to acid hydrolysis ?

• a) A secondary alcohol
• b) Phenol
• c) A primary alcohol
• d) tert-Butyl alcohol

Answer: A secondary alcohol

Question: During reduction of aldehydes with hydrazine and potassium hydroxide, the first step is the formation of

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: The product obtained by the reaction of an aldehyde and hydroxylamine is

• a) aldoxime
• b) alcohol
• c) hydrazone
• d) primary amine

Answer: aldoxime

Question: Which one gives positive iodoform test ?

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question:  The compound that neither forms semicarbazone nor oxime is

• a) CH₃CONHCH₃
• b) CH₃COCH₂Cl
• c) HCHO
• d) CH₃CHO

Answer: CH₃CONHCH₃

Question: Schiff’s reagent gives pink colour with

• a) acetaldehyde
• b) acetic acid
• c) acetone
• d) methyl acetate

Answer: acetaldehyde

Question: Benzophenone can be converted into benzene by using

• a) fused alkali
• b) anhydrous AlCl₃
• c) sodium amalgam in water
• d) acidified dichromate

Answer: fused alkali

Question: In the reaction of NaHSO₃ with carbonyl compounds to form bisulphite product, the nucleophile is

• a)

  

• b)

  

• c) SO₃Na
• d) None of the above

Answer: 

Question: Wolf-Kishner reduction is

• a) reduction of carboxyl compound into alkane
• b) reduction of nitro compound into aniline
• c) reduction of carbonyl compound into alkene
• d) reduction of carbonyl compound into alcohol

Answer: reduction of carboxyl compound into alkane

More Questions...................................

Question: Tollen’s reagent is

• a) ammonical AgNO₃
• b) ammonical CuSO₄
• c) alkaline solution containing complex of copper nitrate
• d) none of these

Answer:  ammonical AgNO₃

Question:

• a) acetal
• b) acid anhydride
• c) diester
• d) hemiacetal

Answer: acetal

Question: Imine derivatives of aldehyde and ketone is called as

• a) Schiff’s base
• b) Schiff’s reagent
• c) Fehling’s reagent
• d) Schiff’s acid

Answer: Schiff’s base

Question: Which reaction is used for detecting the presence of carbonyl group?

• a) All of the above
• b) Reaction with phenyl hydrazine
• c) Reaction with hydroxylamine
• d) Reaction with hydrazine

Answer: All of the above

Question:  The difference between aldol condensation and Cannizzaro’s reaction is that

• a)

  

• b)

  

• c)

  

• d) none of the above

Answer:

Question:

• a) NaBH₄
• b) H₂ /Ni
• c) Both
• d) None of these

Answer: NaBH₄

Question: Which of the following pairs of compounds will undergo aldol and Cannizzaro reaction respectively ?

(i) acetone; benzaldehyde
(ii) acetaldehyde; butan–2–one
(iii) propanone; formaldehyde.
(iv) cyclopentanone, benzaldehyde

• a) (i), (ii) and (iii)
• b) (ii), (iii) and (iv)
• c) (ii) and (iii)
• d) (iii) and (iv)

Answer: (i), (ii) and (iii)

Question: Two compounds benzyl alcohol and benzoic acid are formed from this compound, when this compound is heated in the presence of conc.NaOH, this compound is

• a) Benzaldehyde
• b) Benzylalcohol
• c) Benzophenone
• d) Acetophenone

Answer: Benzaldehyde

Question: The reagent which does not react with both, acetone and benzaldehyde

• a) Fehling’s solution
• b) Grignard reagent
• c) Phenyl hydrazine
• d) Sodium hydrogensulphite

Answer: Fehling’s solution

Question:  Which of the following compounds will give butanone on oxidation with alkaline KMnO₄ solution?

• a) Butan-2-ol
• b) None of these
• c) Butan-1-ol
• d) Both of these

Answer: Butan-2-ol

Question: Which of the following compounds is most reactive towards nucleophilic addition reactions?

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Which of the following does not represent the natural source of the corresponding acids ?

• a) Isobutyric acid : Automobile exhausts
• b) Butyric acid : Rancid butter
• c) Acetic acid : Vinegar
• d) Formic acid : Red ant

Answer: Isobutyric acid : Automobile exhausts

Question: Vinegar is a solution of acetic acid which is :

• a) 6 – 8%
• b) 15 – 20%
• c) 20 –25%
• d) 2 – 4%

Answer: 6 – 8%

Question: Methyl cyanide can be converted into acetic acid by one of the following reactions

• a) Hydrolysis
• b) Decarboxylation
• c) Electrolysis
• d) Reduction

Answer: Hydrolysis

Question: Toluene can be oxidised to benzoic acid by

• a) KMnO₄ (alk.)
• b) K₂Cr₂O₇ (alk.)
• c) Both
• d) None of these

Answer: KMnO₄ (alk.)

Question: Which of the following does the best represent the structure of the carboxylate ion ?

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Select the acid(s) which cannot be prepared by Grignard reagent

• a) Formic acid
• b) Acetic acid
• c) Succinic acid
• d) All of the above

Answer: Formic acid

Question:

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question:

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question:

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Which of the following can not be oxidised to give carboxylic acid?

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Lower carboxylic acids are soluble in water due to

• a) hydrogen bonding
• b) easy hydrolysis
• c) low molecular weight
• d) dissociation into ions

Answer: hydrogen bonding

Question: Dimerisation of carboxylic acids is due to

• a) intermolecular hydrogen bond
• b) coordinate bond
• c) covalent bond
• d) ionic bond

Answer: intermolecular hydrogen bond

Question: Boiling points of carboxylic acids are

• a) higher than corresponding alcohols
• b) equal to that of corresponding alcohols
• c) lower than corresponding alcohols
• d) None of the above

Answer: higher than corresponding alcohols

Question:

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: In the anion HCOO^– the two carbon-oxygen bonds are found to be of equal length. What is the reason for it?

• a) The anion HCOO^– has two reasonating structures
• b) The anion is obtained by removal of a proton from the acid molecule
• c) The C=O bond is weaker than the C–C bond
• d) Electronic orbitals of carbon atom are hybridised

Answer: The anion HCOO^– has two reasonating structures

Question: Carboxylic acids are more acidic than phenol and alcohol because of

• a) resonance stabilization of their conjugate base
• b) highly acidic hydrogen
• c) formation of dimers
• d) intermolecular hydrogen bonding

Answer: resonance stabilization of their conjugate base

Question: Which of the following has the maximum acidic strength ?

• a) o- nitrobenzoic acid
• b) p-nitrobenzoic acid
• c) m-nitrobenzoic acid
• d) p-nitrophenol

Answer: o- nitrobenzoic acid

Question:  Which of the following is the weakest acid ?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Which of the following acids has the smallest dissociation constant ?

• a) BrCH₂CH₂COOH
• b) CH₃CHFCOOH
• c) FCH₂CH₂COOH
• d) None of these

Answer: BrCH₂CH₂COOH

Question: Which one of the following esters is obtained by the esterification of propan-2-ol with ethanoic acid ?

• a) CH₃COOCH(CH₃)₂
• b) (CH₃)₂CHCOOCH₃
• c) CH₃COOCH₂CH₃
• d) None of these

Answer: CH₃COOCH(CH₃)₂

Question: The major product of nitration of benzoic acid is

• a) 3- Nitrobenzoic acid
• b) 2- Nitrobenzoic acid
• c) 4- Nitrobenzoic acid
• d) 2, 4- dinitrobenzoic acid

Answer: 3- Nitrobenzoic acid

Question:  Among the following acids which has the lowest pKa value?

• a) HCOOH
• b) CH₃CH₂COOH
• c) CH₃COOH
• d) None of these

Answer: HCOOH

Question: The correct order of increasing acidic strength is

• a) Ethanol < Phenol < Acetic acid < Chloroacetic acid
• b) Chloroacetic acid < Acetic acid < Phenol < Ethanol
• c) Ethanol < Phenol < Chloroacetic acid < Acetic acid
• d) Phenol < Ethanol < Chloroacetic acid < Acetic acid

Answer: Ethanol < Phenol < Acetic acid < Chloroacetic acid

Question: Which reagent can convert acetic acid into ethanol ?

• a) LiAIH₄ + ether
• b) Sn + HCl
• c) Na + alcohol
• d) H₂ + Pt

Answer: LiAIH₄ + ether

Question: Which is false in case of carboxylic acids?

• a) Which is false in case of carboxylic acids?
• b) They have higher b.p. than corresponding alcohols
• c) They form H-bonds
• d) They are polar molecules

Answer:  Which is false in case of carboxylic acids?

Question: The elimination of CO₂ from a carboxylic acid is known as

• a) decarboxylation
• b) hydration
• c) dehydration
• d) carboxylation

Answer: decarboxylation

Question: The reaction of carboxylic acid gives effervescences of CO₂ with NaHCO₃. The CO₂ comes from

• a) NaHCO₃
• b) None of these
• c) R – COOH
• d) Both

Answer: NaHCO₃

Question: Acetic anhydride is obtained by the reaction of

• a) P₂O₅ and acetic acid
• b) ethanol and acetic acid
• c) ammonia and acetic acid
• d) sodium and acetic acid

Answer: P₂O₅ and acetic acid

Question:  Benzoic acid may be converted to ethyl benzoate by reaction with

• a) dry HCl—C₂H₅OH
• b) sodium ethoxide
• c) ethyl chloride
• d) ethanol

Answer: dry HCl—C₂H₅OH

Question:  Propionic acid with Br₂/P yields a dibromo product. Its structure would be:

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: The product obtained when acetic acid is treated with phosphorus trichloride is

• a) CH₃COCl
• b) CH₃COOPCl₃
• c) ClCH₂COCl
• d) None of these 

Answer:

CH₃COCl

Question:

• a) Hell-Volhard Zelinsky reaction
• b) Cannizzaro reaction
• c) Sandmeyer reaction
• d) Reimer- Tiemann reaction

Answer: Hell-Volhard Zelinsky reaction

Question: Benzoic acid reacts with conc. HNO₃ and H₂SO₄ to give :

• a) 3-Nitrobenzoic acid
• b) 4-Benzene sulphonic acid
• c) 4-Nitrobenzoic acid
• d) 2-Nitrobenzoic acid

Answer: 3-Nitrobenzoic acid

Question:

• a) RCHBrCOOH ; RCH(NH₂)COOH
• b) RCHBrCONH₂ ; RCH(NH₂)COOH
• c) RCH₂COBr ; RCH₂COONH₄
• d) None of these

Answer: RCHBrCOOH ; RCH(NH₂)COOH

Question:

• a) all the above factors
• b) taking acetic acid in excess
• c) taking ethanol in excess
• d) removing water

Answer: all the above factors

Question: A carboxylic acid can best be converted into acid chloride by using

• a) ClCOCOCl
• b) SOCl₂
• c) PCl₅
• d) HCl

Answer: ClCOCOCl

Question:

• a)  IV > III > II > I
• b) III > IV > II > I
• c) I > II > III > IV
• d) II > IV > III > I

Answer: IV > III > II > I

Question: The strongest acid among the following is –

• a) Salicylic acid
• b) m-hydroxybenzoic acid
• c) p-hydroxybenzoic acid
• d) Benzoic acid

Answer: Salicylic acid

Question: Among the following, the most acidic is

• a) Cl₂CHCOOH
• b) CH₃COOH
• c) ClCH₂COOH
• d) None of these

Answer: Cl₂CHCOOH