JEE Chemistry Aldehydes Ketones and Carboxylic Acids MCQs Set A

Question:

• a) 2- methylbutanal
• b) Butan - 2- aldehyde
• c) 3- methylisobutyraldehyde
• d) 2- ethylpropanal

Answer: 2- methylbutanal

Question: The IUPAC name of the compound having the molecular formula Cl₃C –CH₂CHO is

• a) 3, 3, 3- trichloropropanal
• b) 1, 1, 1- trichloropropanal
• c) 2, 2, 2- trichloropropanal
• d) Chloral

Answer: 3, 3, 3- trichloropropanal

Question: The IUPAC name of CH₃COCH(CH₃)₂ is

• a) 3-methyl-2-butanone
• b) 2-methyl-3-butanone
• c) 4-methylisopropyl ketone
• d) Isopropylmethyl ketone

Answer: 3-methyl-2-butanone

Question:

• a) 4-hydroxy 2-methyl benzaldehyde
• b) 4-formyl 3-methyl phenol
• c) 4-formyl 3-methyl 1-hydroxy benzene
• d) 4-hydroxy 2-methyl carbaldehyde

Answer: 4-hydroxy 2-methyl benzaldehyde

Question: IUPAC name of ethyl isopropyl ketone is

• a) 2-methyl pent-3-one
• b) 2-methyl pent-2-one
• c) 4-methyl pent-3-one
• d) 4-methyl pent-2-one

Answer: 2-methyl pent-3-one

Question: In > C = O group sigma bond is formed by

• a) sp²-p-overlapping
• b) sp³-p-overlapping
• c) s-p-overlapping
• d) sp-p-overlapping

Answer: sp²-p-overlapping

Question:

• a) p-p-overlapping
• b) p-d-overlapping
• c) s-s-overlapping
• d) s-p-overlapping

Answer: p-p-overlapping

Question: Which of the following is correct for carbonyl compounds?

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Which of the following contain an aldehyde?

• a) All of these
• b) Meadow sweet
• c) Vanilla beans
• d) Cinnamon

Answer: All of these

Question: Which of the following have pleasant smell?

• a) Hexanal
• b) Propanal
• c) Methanal
• d) Ethanal

Answer:  Hexanal

Question: Which one of the following can be oxidised to the corresponding carbonyl compound?

• a) 2-hydroxy-propane
• b) Ortho-nitrophenol
• c) Phenol
• d) 2-methyl-2 hydroxy-propane

Answer: 2-hydroxy-propane

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

Question: Which one of the following on oxidation gives a ketone ?

• a) Secondary alcohol
• b) All of these
• c) Primary alcohol
• d) Tertiary alcohol

Answer: Secondary alcohol

Question: What is formed when a primary alcohol undergoes catalytic dehydrogenation

• a) Aldehyde
• b) Alkene
• c) Ketone
• d) Acid

Answer: Aldehyde

Question: Primary and secondary alcohols on action of reduced copper give

• a) Aldehydes and ketones respectively
• b) Ketones and aldehydes respectively
• c) Only aldehydes
• d) Only ketones

Answer: Aldehydes and ketones respectively

Question:

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: The catalyst used in Rosenmund's reduction is

• a) Pd/BaSO₄
• b) HgSO₄
• c) anhydrous ZnCl₂
• d) None of these

Answer:  Pd/BaSO₄

Question:

• a) Stephen’s reaction
• b) Sandorn's reaction
• c) Mendius reaction
• d) Rosenmund's reaction

Answer:  Stephen’s reaction

Question: Benzaldehyde can be prepared by oxidation of toluene by

• a)

  

• b)

  

• c) Acidic KMnO₄
• d) All of these

Answer: 

Question: The oxidation of toluene to benzaldehyde by chromyl chloride is called

• a) Etard reaction
• b) Rosenmund reaction
• c) Wurtz reaction
• d) Fittig reaction

Answer: Etard reaction

Question: An aldehyde group can be present

• a) only at the end of carbon chain
• b) at the second carbon atom of the carbon chain
• c) at any position in carbon atom
• d) in between carbon chain

Answer: only at the end of carbon chain

Question: Benzaldehyde is obtained from Rosenmund’s reduction of

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Which of the following is not used in the preparation of ketone?

• a) Acid hydrolysis of alkyl cyanide
• b) Pyrolysis of calcium acetate
• c) Dehydrogenation of 2° alcohol
• d) Oxidation of secondary alcohols

Answer:  Acid hydrolysis of alkyl cyanide

Question:

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Find out B in the given reactions

• a) acetophenone
• b) benzaldehyde
• c) cyclohexyl carbaldehyde
• d) benzoic acid

Answer: acetophenone

Question:

• a) Gatterman-Koch reaction
• b) Stephen’s reaction
• c) Rosenmund’s reaction
• d) Cannizzaro’s reaction

Answer: Gatterman-Koch reaction

Question: Which aldehyde cannot be obtained by Rosenmund’s reaction?

• a) HCHO
• b) CH₃CHO
• c) CH₃CH₂CHO
• d) All of these

Answer: HCHO

Question:

• a) CH₃MgBr followed by hydrolysis
• b) I₂ – NaOH, CH₃I
• c) Dil. H₂SO₄ followed by reaction with CH₂N₂
• d) None of these

Answer: CH₃MgBr followed by hydrolysis

Question: Which of the following is used to prepare ketone from acyl chloride ?

• a) R₂Cd
• b) CrO₃
• c) R-MgX
• d) CO + HCl

Answer: R₂Cd

Question: Which of the following forces explain the boiling point of aldehydes and ketones?

• a) Dipole-dipole attraction
• b) Hydrogen bonding
• c) van der Waal’s forces
• d) None of these

Answer: Dipole-dipole attraction

Question: Which is highly soluble in water?

• a) Methanal
• b) Propanone
• c) Propanal
• d) Butanone

Answer: Methanal

Question: Propanal and propanone, both have same molecular formula(C₃H₆O), what do you expect about their boiling points?

• a) Boiling point of propanal is lower than the boiling point of propanone
• b) Boiling point of propanal is higher than the boiling point of propanone
• c) None of these
• d) Nothing can be predicted

Answer: Boiling point of propanal is lower than the boiling point of propanone

Question: Less reactivity of ketone is due to

• a) Both
• b) + I inductive effect decrease positive charge on carbonyl carbon atom
• c) steric effect of two bulky alkyl groups
• d) None of these

Answer: Both

Question: Acetaldehyde reacts with

• a) Nucleophiles only
• b) Free radicals only
• c) Both electrophiles and nucleophiles
• d) Electrophiles only

Answer: Nucleophiles only

Question: Carbonyl compounds undergo nucleophilic addition because of

• a) more stable anion with negative charge on oxygen atom and less stable carbonium ion
• b) electromeric effect
• c) electronegativity difference of carbon and oxygen atoms
• d) None of the above

Answer: more stable anion with negative charge on oxygen atom and less stable carbonium ion

Question: Which of the following statement is false ?

• a) None of the above
• b) Aldol condensation is given by aldehydes and ketones in presence of acids
• c) Aldol condensation is given by aldehydes in presence of alkali
• d) Cannizzaro reaction is given by aldehydes in presence of alkali

Answer: None of the above

Question: If formaldehyde and KOH are heated, then we get

• a) methyl alcohol
• b) acetylene
• c) methane
• d) ethyl formate

Answer: methyl alcohol

Question: The reagent which can be used to distinguish acetophenone from benzophenone is

• a) I₂ and Na₂CO₃
• b) benedict reagent
• c) aqueous solution of NaHSO₃
• d) 2,4- dinitrophenylhydrazine

Answer:  I₂ and Na₂CO₃

Question: Benzaldehyde reacts with ethanoic KCN to give

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Acetone reacts with iodine (I₂) to form iodoform in the presence of

• a) NaOH
• b) MgCO₃
• c) CaCO₃
• d) KOH

Answer: NaOH

Question: (CH₃)₃C–CHO does not undergo aldol condensation due to

• a) absence of alpha hydrogen atom in the molecule
• b) cleavage taking place between —C— CHO bond
• c) three electron donating methyl groups
• d) bulky (CH₃)₃C—group

Answer: absence of alpha hydrogen atom in the molecule

Question: Acetaldehyde reacts with semicarbazide and forms semicarbazone. Its structure is

• a) CH₃CH = NNHCONH₂
• b) CH₃CH = NNHCON = CHCH₃
• c) CH₃CH = N—CONHNH₂
• d) None of these

Answer: CH₃CH = NNHCONH₂

Question:  Iodoform test is not given by

• a) 3-Pentanone
• b) Ethanol
• c) 2-Pentanone
• d) Ethanal

Answer: 3-Pentanone

Question: Phenylmethyl ketone can be converted into ethylbenzene in one step by which of the following reagents?

• a) Zn-Hg/HCl
• b) CH₃MgI
• c) LiAlH₄
• d) NaBH₄

Answer: Zn-Hg/HCl

Question: When acetaldehyde is heated with Fehling’s solution it gives a precipitate of

• a) Cu₂O
• b) Cu
• c) CuO
• d) Cu(OH)₂

Answer: Cu₂O

Question: Aldol condensation would not occur in

• a) HCHO
• b) CH₃COCH₃
• c) CH₃CH₂CHO
• d) CH₃CHO

Answer: HCHO

Question: Cannizzaro reaction occurs with

• a) C₆H₅CHO
• b) CH₃CHO
• c)

  

• d)

  

Answer: C₆H₅CHO

Question: Which of the following compound will show positive silver mirror test ?

• a) Both
• b) HCOOH
• c) CH₃ (CHOH)₃CHO
• d) None of these

Answer: Both

Question: Aldehydes and ketones are distinguished by which of the following test ?

• a) Tollen’s test
• b) Lucas test
• c) KMnO₄ solution (Baeyer’s test)
• d) None of these

Answer: Tollen’s test

Question: Aldehydes and ketones are generally reduced by

• a) Clemmensen reduction
• b) H₂S
• c) H₂ / Ni
• d) None of these

Answer: Clemmensen reduction

Question: In which reaction, > C = O can be reduced to > CH₂?

• a) Wolf-Kishner reaction
• b) Reimer-Tiemann reaction
• c) Wurtz reaction
• d) None of these

Answer: Wolf-Kishner reaction

Question:  A compound does not react with 2, 4-dinitrophenylhydrazine, the compound is

• a) CH₃OH
• b) Acetone
• c) Acetaldehdye
• d) None of these

Answer: CH₃OH

Question: Which gives lactic acid on hydrolysis after reacting with HCN ?

• a) CH₃CHO
• b) HCHO
• c) C₆H₅CHO
• d) CH₃COCH₃

Answer: CH₃CHO

Question: The most appropriate reagent to distinguish between acetaldehyde and formaldehyde is

• a) Iodine in presence of base
• b) Schiff’s reagent
• c) Tollen’s reagent
• d) Fehling’s solution

Answer: Iodine in presence of base

Question: Aldehydes can be oxidised by

• a) All the above
• b) Fehling solution
• c) Tollen’s reagent
• d) Benedict solution

Answer:  All the above

Question: 2-pentanone and 3-pentanone can be distinguished by

• a) Iodoform reaction
• b) Aldol condensation
• c) Cannizaro's reaction
• d) None of these

Answer: Iodoform reaction

Question: Cross aldol condensation occurs between

• a) two different aldehydes and ketones
• b) two same ketones
• c) two same aldehydes
• d) None of these

Answer: two different aldehydes and ketones

Question: Ketone upon treatment with Grignard Reagent gives

• a) tertiary alcohol
• b) primary alcohol
• c) secondary alcohol
• d) aldehyde

Answer: tertiary alcohol

Question: When acetaldehyde reacts with alcohol then produce

• a) Acetal
• b) Acetone
• c) Ketal
• d) None

Answer:  Acetal

Question: The product formed in Aldol condensation is

• a) a beta-hydroxy aldehyde or a beta-hydroxy ketone
• b) an alpha-hydroxy aldehyde or ketone
• c) an alpha, beta unsaturated ester
• d) a beta-hydroxy acid

Answer: a beta-hydroxy aldehyde or a beta-hydroxy ketone

Question: Clemmensen reduction of a ketone is carried out in the presence of which of the following ?

• a) Zn-Hg with HCl
• b) H₂ and Pt as catalyst
• c) Glycol with KOH
• d) LiAlH₄

Answer: Zn-Hg with HCl