CBSE Class 12 Chemistry Aldehydes Ketones and Carboxylic Acids MCQs Set A

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 : Which is highly soluble in water?

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

Answer : A

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 : 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 : Acetaldehyde reacts with

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

Answer : B

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 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 : If formaldehyde and KOH are heated, then we get

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

Answer : B

Question : Aldehydes can be oxidised by :

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

Answer : D

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

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

Answer : A

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 : 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 : 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 : 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 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