CUET Chemistry MCQs Unit XII Aldehydes Ketones and Carboxylic Acids

Question : Which is highly soluble in water?

(a) Methanal  

(b) Propanal

(c) Propanone

(d) Butanone

Answer : A

Question : Carbonyl compounds undergo nucleophilic addition because of

(a) electronegativity difference of carbon and oxygen atoms

(b) electromeric effect

(c) more stable anion with negative charge on oxygen atom and less stable carbonium ion

(d) None of the above

Answer : C

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

(a) Hydrogen bonding       

(b) van der Waal’s forces

(c) Dipole-dipole attraction

(d) None of these

Answer : C

Question : Carbonyl compounds undergo nucleophilic addition because of

(a) electronegativity difference of carbon and oxygen atoms

(b) electromeric effect

(c) more stable anion with negative charge on oxygen atom and less stable carbonium ion

(d) None of the above

Answer : C

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

(a) Cannizaro's reaction

(b) Aldol condensation

(c) Iodoform reaction   

(d) Clemmensen's reduction

Answer : C

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

(a) sp₂-p-overlapping

(b) sp3-p-overlapping

(c) sp-p-overlapping

(d) s-p-overlapping

Answer : A

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 : A

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 : A

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

(a) 15 – 20%

(b) 20 –25%

(c) 6 – 8% 

(d) 2 – 4%

Answer : C

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

(a) Reduction 

(b) Hydrolysis

(c) Electrolysis

(d) Decarboxylation

Answer : B

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

(a) hydrazone 

(b) aldoxime

(c) primary amine

(d) alcohol

Answer : B

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

(a) Hydrogen bonding

(b) van der Waal’s forces

(c) Dipole-dipole attraction

(d) None of these

Answer : C

Question : Acetaldehyde reacts with

(a) Electrophiles only

(b) Nucleophiles only

(c) Free radicals only

(d) Both electrophiles and nucleophiles

Answer : B

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

(a) 2,4- dinitrophenylhydrazine

(b) aqueous solution of NaHSO₃

(c) benedict reagent

(d) I2and Na₂CO₃ 

Answer : D

Question : Tollen’s reagent is

(a) ammonical CuSO₄

(b) ammonical AgNO₃

(c) alkaline solution containing complex of copper nitrate

(d) none of these

Answer : B

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

(a) Sodium hydrogensulphite

(b) Phenyl hydrazine

(c) Fehling’s solution

(d) Grignard reagent

Answer : C

Question : Aldehydes and ketones are generally reduced by :

(a) Clemmensen reduction

(b) H₂S

(c) H2 / Ni

(d) None of these

Answer : A

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 : A

Question : An aldehyde group can be present

(a) in between carbon chain

(b) at any position in carbon atom

(c) only at the end of carbon chain

(d) at the second carbon atom of the carbon chain

Answer : C

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

(a) Both have same boiling point

(b) Boiling point of propanal is higher than the boiling point of propanone.

(c) Boiling point of propanal is lower than the boiling point of propanone

(d) Nothing can be predicted

Answer : C

Question : Which of the following statement is false ?

(a) Cannizzaro reaction is given by aldehydes in presence of alkali

(b) Aldol condensation is given by aldehydes in presence of alkali

(c) Aldol condensation is given by aldehydes and ketones in presence of acids

(d) None of the above

Answer : D

Question : Schiff’s reagent gives pink colour with

(a) acetaldehyde 

(b) acetone

(c) acetic acid

(d) methyl acetate

Answer : A

Question : The π-bond in carbonyl group is formed by

(a) s-s-overlapping

(b) p-p-overlapping

(c) s-p-overlapping

(d) p-d-overlapping

Answer : B

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

(a) Primary alcohol

(b) Secondary alcohol

(c) Tertiary alcohol

(d) All of these

Answer : B

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

(a) Rosenmund reaction

(b) Wurtz reaction

(c) Etard reaction

(d) Fittig reaction

Answer : C

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

(a) the former takes place in the presence of -H-atom.

(b) the former takes place in the absence of -H-atom.

(c) the former takes place in the presence of -H-atom.

(d) none of the above

Answer : A

Question : Which is highly soluble in water?

(a) Methanal

(b) Propanal

(c) Propanone

(d) Butanone

Answer : A

Question : Which of the following statement is false ?

(a) Cannizzaro reaction is given by aldehydes in presence of alkali

(b) Aldol condensation is given by aldehydes in presence of alkali

(c) Aldol condensation is given by aldehydes and ketones in presence of acids

(d) None of the above

Answer : B

Question : Iodoform test is not given by

(a) 2-Pentanone

(b) Ethanol

(c) Ethanal

(d) 3-Pentanone

Answer : D

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

(a) HCOOH

(b) CH₃ (CHOH)₃CHO

(c) CH₃CO(CHOH)CH₃

(d) Both (a) and (b)

Answer : D

Question : Which of the following have pleasant smell?

(a) Methanal

(b) Propanal

(c) Ethanal  

(d) Hexanal

Answer : D

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

(a) Rosenmund reaction

(b) Wurtz reaction

(c) Etard reaction        

(d) Fittig reaction

Answer : C

Question : Acetaldehyde reacts with

(a) Electrophiles only

(b) Nucleophiles only

(c) Free radicals only

(d) Both electrophiles and nucleophiles

Answer : B

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

(a) 2-methyl-3-butanone

(b) 4-methylisopropyl ketone

(c) 3-methyl-2-butanone

(d) Isopropylmethyl ketone

Answer : C

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

(a) Formic acid : Red ant

(b) Acetic acid : Vinegar

(c) Butyric acid : Rancid butter

(d) Isobutyric acid : Automobile exhausts 

Answer : D

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

(a) Reaction with hydrazine

(b) Reaction with phenyl hydrazine

(c) Reaction with hydroxylamine

(d) All of the above

Answer : D

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

(a) Both have same boiling point

(b) Boiling point of propanal is higher than the boiling point of propanone.

(c) Boiling point of propanal is lower than the boiling point of propanone

(d) Nothing can be predicted

Answer : C

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

(a) CaCO₃

(b) NaOH

(c) KOH

(d) MgCO₃

Answer : B

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

(a) Lucas test

(b) Tollen’s test

(c) KMnO₄ solution (Baeyer’s test)

(d) None of these

Answer : B

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

(a) Aldehyde

(b) Ketone

(c) Alkene   

(d) Acid

Answer : A

Question : Less reactivity of ketone is due to

(a) + I inductive effect decrease positive charge on carbonyl carbon atom

(b) steric effect of two bulky alkyl groups

(c) sp² hybridised carbon atom of carbonyl carbon atom

(d) Both (a) and (b)

Answer : D

Question : Which of the following contain an aldehyde?

(a) Vanilla beans

(b) Meadow sweet

(c) Cinnamon

(d) All of these

Answer : D

Question : Benzaldehyde can be prepared by oxidation of toluene by

(a) Acidic KMnO₄

(b) K₂Cr₂O₇ / H+

(c) CrO₂Cl₂

(d) All of these

Answer : C

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) Acetophenone

(d) Benzophenone

Answer : A

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

(a) methane

(b) methyl alcohol

(c) ethyl formate

(d) acetylene

Answer : B

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

(a) Cu

(b) CuO

(c) Cu₂O

(d) Cu(OH)₂

Answer : C

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

(a) Primary alcohol 

(b) Secondary alcohol

(c) Tertiary alcohol

(d) All of these

Answer : B

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

(a) Hydrogen bonding       

(b) van der Waal’s forces

(c) Dipole-dipole attraction

(d) None of these

Answer : C

Question : Aldehydes can be oxidised by :

(a) Tollen’s reagent 

(b) Fehling solution

(c) Benedict solution

(d) All the above

Answer : D

Question : What is formed when a primary alcohol undergoes catalytic ehydrogenation ?

(a) Aldehyde

(b) Ketone

(c) Alkene

(d) Acid

Answer : A

Question : Ketone upon treatment with Grignard Reagent gives

(a) primary alcohol

(b) secondary alcohol

(c) tertiary alcohol 

(d) aldehyde

Answer : C

Question : Wolf-Kishner reduction is

(a) reduction of carbonyl compound into alcohol

(b) reduction of carbonyl compound into alkene

(c) reduction of carboxyl compound into alkane

(d) reduction of nitro compound into aniline

Answer : C

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 : A

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

(a) Oxidation of secondary alcohols

(b) Dehydrogenation of 2° alcohol

(c) Pyrolysis of calcium acetate

(d) Acid hydrolysis of alkyl cyanide

Answer : D

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

(a) methane       

(b) methyl alcohol

(c) ethyl formate

(d) acetylene

Answer : B

Question : The catalyst used in Rosenmund's reduction is

(a) HgSO₄

(b) Pd/BaSO₄

(c) anhydrous AlCl3

 (d) anhydrous ZnCl₂

Answer : B

Question : Less reactivity of ketone is due to

(a) + I inductive effect decrease positive charge on carbonyl carbon atom

(b) steric effect of two bulky alkyl groups

(c) sp2 hybridised carbon atom of carbonyl carbon atom

(d) Both (a) and (b)

Answer : D

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

(a) LiAlH4

(b) Zn-Hg/HCl

(c) NaBH4

(d) CH3MgI

Answer : B

Question : Primary and secondary alcohols on action of reduced coppergive

(a) Aldehydes and ketones respectively

(b) Ketones and aldehydes respectively

(c) Only aldehydes

(d) Only ketones

Answer : A

Question : IUPAC name of ethyl isopropyl ketone is

(a) 4-methyl pent-3-one

(b) 2-methyl pent-3-one

(c) 4-methyl pent-2-one

(d) 2-methyl pent-2-one

Answer : B

Question : Benzophenone can be converted into benzene by using

(a) fused alkali

(b) anhydrous AlCl₃

(c) sodium amalgam in water

(d) acidified dichromate

Answer : A

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) and (iii)

(c) (ii), (iii) and (iv) (d) (iii) and (iv)

Answer : A

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

(a) Butan-1-ol

(b) Butan-2-ol

(c) Both of these

(d) None of these

Answer : B

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

(a) Oxidation of secondary alcohols

(b) Dehydrogenation of 2° alcohol

(c) Pyrolysis of calcium acetate

(d) Acid hydrolysis of alkyl cyanide

Answer : D

Question : Which of the following contain an aldehyde?

(a) Vanilla beans

(b) Meadow sweet

(c) Cinnamon    

(d) All of these

Answer : D

Question : Which of the following have pleasant smell?

(a) Methanal

(b) Propanal

(c) Ethanal

(d) Hexanal

Answer : D

Question : Imine derivatives of aldehyde and ketone is called as

(a) Schiff’s reagent

(b) Fehling’s reagent

(c) Schiff’s base 

(d) Schiff’s acid

Answer : C

Question : An aldehyde group can be present

(a) in between carbon chain

(b) at any position in carbon atom

(c) only at the end of carbon chain

(d) at the second carbon atom of the carbon chain

Answer : C