MCQ Chapter 12 Aldehydes Ketones and Carboxylic Acids Class 12 Chemistry

Please refer to Aldehydes Ketones and Carboxylic Acids MCQ Questions Class 12 Chemistry below. These MCQ questions for Class 12 Chemistry with answers have been designed as per the latest NCERT, CBSE books and syllabus issued for the current academic year. These objective questions for Aldehydes Ketones and Carboxylic Acids will help you to prepare for the exams and get more marks.

Aldehydes Ketones and Carboxylic Acids MCQ Questions Class 12 Chemistry

Please see solved MCQ Questions for Aldehydes Ketones and Carboxylic Acids in Class 12 Chemistry. All questions and answers have been prepared by expert faculty of standard 12 based on latest examination guidelines.

Question. What represents the best method for producing salicylic acid?
(a) Benzoic acid, strong base, high temperature
(b) Toluene, strong base, water, high temperature
(c) Phenol, base carbondioxide then acid
(d) Bromobenzene, carbonic acid, high temperature     

Question. Which reaction is suitable for the preparation of α-chloroacetic acid?
(a) Hell-Volhard-Zelinsky reaction
(b) Nefreaction
(c) Stephen’s reaction
(d) Perkin condensation     

Question. Cross aldol condensation occurs between
(a) two same aldehydes
(b) two same ketones
(c) two different aldehydes and ketones
(d) None of the above     

Question. Match the following columns. 

     A  B  C  D
(a) 3  1  4  2 
(b) 4  2  2  1  
(c) 2  3  1  4
(d) 3  4  1  2       

Question. Main product obtained from the reaction of ammonia and formaldehyde is 
(a) formic acid
(b) methylamine
(c) methanol
(d) urotropine       

Question. Which of the following compounds would be the main product of an aldol condensation of acetaldehyde and acetone? 
(a) CH₃CH = CH·CHO
(b) CH₃CH = CHCOCH₃
(c) (CH₃)₂C = CH·CHO
(d) (CH₃)₂C = CHCOCH₃       

Question. Which of the following, is an example of aJdol condensation?

Question. In which of the below reaction do we find α,β-unsaturated carbonyl compounds undergoing a ring closure reaction with conjugated dienes? 
(a) Perkin reaction
(b) Diels-Alder reaction
(c) Claisen rearrangement
(d) Hofmann reaction       

Question. A compound ‘A’ having the molecular formula C₅H₁₂O,on oxidation gives a compound ‘B’ with molecular formula C₅H₁₀O. Compound ‘B’ gave a 2, 4-dinitrophenylhydrazine derivative but did not answer haloform test or silver mirror test. The structure of compound ‘A’ is

Question. An organic compound of molecular formula C₃H₆O did not give a silver mirror with Tollen ‘s reagent, but gave an oxime with hydroxylarnine, it may be
(a) CH₃—CO—CH₃
(b) C₂H₅CHO
(c) CH₂ = CH—CH₂—OH
(d) CH₃—O—CH = CH₂       

Question.

Question. The most reactive compound towards formation of cyanohydrin on treatment with HCN followed by acidification is
(a) benzaldehyde
(b) p -nitrobenzaldehyde
(c) phenylacetaldehyde
(d) p-hydroxybenzaldehyde       

Question. What product is formed in the reaction

Question. When acetaldehyde is heated with Fehling’s solution, a red precipitate is formed. Which of the following is that?
(a) Cu₂O
(b) Cu 
(c) CuO
(d) CuSO₄       

Question. What is the oxidation number of carbonyl carbon in acetophenone? 
(a) + 3
(b) + 1
(c) + 2
(d) Zero       

Question. p-cresol reacts with chloroform in alkaline medium to give the compound A which adds hydrogen cyanide to form the compound B. The latter on acidic hydrolysis gives chiral carboxylic acid. The structure of the carboxylic acid is

Question. In a reaction RCHO is reduced to RCH₃ using amalgamated zinc and concentrated HCl and wanning the solution. The reaction is known as 
(a) Meerwein-Ponndorf reaction
(b) Clemmensen’s reduction
(c) Wolff-Kishner reduction
(d) Schiff’s reaction       

Question. Which of the following reactions can be used to change benzaldehyde to cinnarnic acid?
(a) Perkin’s reaction 
(b) Knoevenagel reaction
(c) Reformatsky reaction and ketones
(d) Benzoin condensation     

Question. An organic compound Xis oxidised by using acidified K₂Cr₂O₇ . The product obtained reacts with phenyl hydrazine but does not answer silver mirror test. The possible structure of X is 
(a) CH₃CH₂OH
(b) CH3—C—CH₃
              ll
              O
(c) (CH₃ )₂ CHOR
(d) CH₃CHO     

Question. CH₃COOH →^LialH₄ X →_300°C ^Cu y →_NaOH^Dilute Z In the above reaction, Z is
(a) butanol
(b) aldol
(c) ketol
(d) acetal       

Question. Which factor/s will increase the reactivity of ›C = O group? 
I. Presence ofa group with positive inductive effect.
II. Presence of a group with negative inductive effect.
III. Presence of large alkyl group.
(a) Only I
(b) Only II
(c) I and III
(d) II and III       

Question. Benzaldehyde reacts with ammonia to form 
(a) benzaldehyde ammonia
(b) urotropine
(c) hydrobenzamide
(d) ammonium chloride     

Question. Which product is obtained on reduction of methanal in the presence of concentrated NaOH?
(a) Formic acid and methyl alcohol
(b) CO + H₂
(c) Methyl alcohol
(d) Formic acid     

Question. An aromatic compound ‘X’ with molecular formula C₉H₁₀O gives the following chemical tests
I. Forms 2, 4-DNP derivative,
II. Reduces Tollen’s reagent,
III. Undergoes Cannizzaro reaction and,
IV. On vigorous oxidation 1, 2-benzenedicarboxylic acid is obtained. Xis 

Question. In the following reaction sequence, the correct structures of E, F and G are

Question. Acetone on addition to methyl magnesiwn bromide forms a complex, which on decomposition with acid gives X and Mg(OH)Br. Which one of the following is X?
(a) CH₃ OH 
(b) (CH₃)₃ COH
(c) (CH₃)₂ CHOH
(d) CH₃CH₂OH       

Question. C₆H₅CHO→^NH₃? 
(a) (C₆H₅CHN)₂ CH·C₆H₅
(b) C₆H₅NHCH₃
(c) C₆H₅CH₂NH₂
(d) C₆H₅NHC₆H₅     

Question. Predict the product, 

Question. The end product ‘C’ in the following sequence of chemical reactions is
 CH₃COOH →^CaCO₃ A →^HeatB →^NH₂OH C 
(a) acetaldehyde oxime
(b) formaldehyde oxime
(c) methyl nitrate
(d) acetoxime     

Question. Which reaction, intermediate is formed during the condensation reaction between acetaldehyde and formaldehyde? 
(a) : ^–CH₂CHO
(b) ⁺CH₂CHO
(c) ⁺CH₂OH
(d) : ^–CHCHO       

Question. Which of the following organic compounds answers to both iodoform test and Fehling’s test? 
(a) Ethanol
(b) Methanal
(c) Ethanal
(d) Propanone       

Question. On reaction with hydroxylamine, aldehydes produce
(a) ketoxime
(b) hydrazone 
(c) semicarbazone
(d) aldoxime     

Question. Benzaldehyde and acetone can be best distinguished using
(a) Fehling’s solution 
(b) sodium hydroxide solution
(c) 2, 4-DNP
(d) Tollen’s reagent   

Question. Identify the reaction which is used to obtain β- hydroxy ketone. 
(a) Condensation reaction
(b) Aldo! condensation
(c) Cross aldol condensation
(d) Cannizzaro reaction   

Question. CH3CHO + HCHO →HeatDil. NaOH  A
                                              →H3O+HCN  B
The structure of compound B is 

Question.  

Question. Self condensation of acetaldehyde in the presence of dilute alkalies gives
(a) an acetal
(b) an aldol
(c) mesitylene
(d) propionaldehyde       

Question.

Question. The reaction of CO₂ with sodium phenoxide at 400 K result in
(a) benzoic acid
(b) sodium benzoate
(c) salicylaldehyde
(d) sodium salicylate       

Question. Q11T2
Identify Z from the following. 
(a) Ethyl acetate
(b) Acetic acid
(c) Propanoic acid
(d) Methyl acetate     

Question. Claisen condensation is not given by 

Question. Formalin is the commercial name of
(a) formic acid
(b) fluroform
(c) 40% aqueous solution of methanal
(d) para-formaldehyde   

Question. Which does not react with Fehling’s solution?
(a) CH₃CHO
(b) C₆H₅CHO 
(c) C₆H₁₂O₆
(d) HCOOH     

Question. 

(a) an ester
(b) an anhydride
(c) acetal
(d) hemiacetal     

Question. The product formed when hydroxylamine condenses with a carbonyl compound is called 
(a) hydrazide
(b) oxime
(c) hydrazine
(d) hydrazone   

Question. Which of the following acids dissociates to the greatest extent in aqueous solution? 
(a) Trichloroacetic acid
(b) Acetic acid
(c) Chloroacetic acid
(d) Dichloroacetic acid       

Question. With reference to the scheme given, which of the given statement (s) about T,U, V and Wis (are) correct?

(a) Tis soluble in hot aqueous NaOH
(b) U is optically active
(c) Molecular formula of Wis C₁₀H₁₈O₄
(d) V gives effervescence on treatment with aqueous NaHCO₃     

Question. The total number of carboxylic acid groups in the product P is 

(a) 5
(b) 2
(c) 4
(d) 3       

Question. Benzaldehyde reacts with methyl amine to give
(a) C₆H₅NH₂
(b) C₆H₅CH₂ NI-I₂
(c) C₆H₅CH=NCH₃
(d) C₆H₅CONH₂     

Question. CH₃COOH →^Br₂/P Y→^{(i) KC}_(ii)H3O⁺ X. Here, X is
(a) glycollic acid
(b) α-hydroxy propionic acid
(c) succinic acid
(d) malonic acid   

Question. The compound I, is

Question. Compound (A )(molecular formula C₃H₈O) is treated with acidified potassium dichromate to form a product B (molecular formula C₃H₆O). ‘B’ forms a shining silver m.itTor on wanning with ammoniacal silver nitrate. ‘B’ when treated with an aqueous solution of H₂NCONHNH₂ · HCl and sodium acetate gives a product’ C’. Identify the structure of ‘C’.
(a) CH₃CH₂CH = NNHCONH₂
(b) (CH₃)₂C=NNHCONH₂
(c) (CH₃)₂C = NCONHNH₂
(d) CH₃CH₂CH=NCONHNH₂     

Question. The product fonned in the reaction

Question. A compound, containing only carbon, hydrogen and oxygen, has a molecular weight of 44. On complete oxidation, it is converted into a compound of molecular weight 60. The original compound is 
(a) an aldehyde
(b) an acid
(c) an alcohol
(d) an ether       

Question. CH₃—CHO+ HCN→ A
Compound A on hydrolysis gives
(a) CH₃ — CH₂ — COOH
(b) CH₃ — CH₂ — CH₂ — NH₂
(c) CH₃ — CO — COOH
(d) CH₃ — CO — CH=NOH
(e) CH₃ — CH — COOH
                 l
                OH               

Question. Which of the following does not undergo Cannizz.aro’s reaction? 
(a) Benzaldebyde
(b) 2-methylpropanal
(c) p-methoxybenzaldebyde
(d) 2, 2-dimethylpropanal
(e) Formaldehyde   

Question. Cyanohydrin of which of the following forms lactic acid?
(a) HCHO
(b) CH₃COCH₃
(c) CH₃CHO
(d) CH₃CH₂CHO         

Question. A and B in the following reaction are 

Question. Which one of the following is reduced with zinc and hydrochloric acid to give the corresponding hydrocarbon?
(a) Ethyl acetate 
(b) Acetic acid
(c) Acetamide
(d) Butan-2-one       

Question.

Question. Aldehyde with NH₂ · NH₂ forms 
(a) hydrazones
(b) aniline
(c) nitrobenzene
(d) None of the above   

Question. The increasing order of the rate of HCN addition to compounds A – D is
(A) HCHO
(B) CH₃COCH₃
(C) PhCOCH₃
(D) PhCOPh 
(a) A < B < C < D
(b) D < B < C < A
(c) D < C < B < A
(d) C < D < B < A       

Question. The enol form of acetone after treatment with D₂O, give

Question. Benedict’s solution is not reduced by
(a) formaldehyde
(b) acetaldehyde
(c) glucose
(d) acetic anhydride       

Question. Acetone reacts with Grignard reagent to form 
(a) 3° alcohol
(b) 2° alcohol
(c) ether
(d) No reaction       

Question. Q

The compound (X) is
(a) CH₃—COOH
(b) BrCH₂—COOH
(c) (CH₃CO)₂O
(d) CHO—COOH     

Question. Benzyl alcohol and sodium benzoate is obtained by the action of sodium hydroxide on benzaldehyde. This reaction is known as
(a) Perkin’s reaction
(b) Cannizzaro’s reaction
(c) Sandmeyer’s reaction
(d) Claisen condensation       

Question. The end products in benzaldehyde are
(a) PhCO₂H,PhCH₂OH
(b) PhCO₂H,PhCH₂CO₂H
(c) PhCH₂OH, PhCOCH₃
(d) PhCO₂H,PhCOCH₃     

Question. Acetals are
(a) ketones
(b) di ethers
(c) aldehyde
(d) hydroxy aldehydes   

Question. Aldehydes can be oxidised by 
(a) Tollen’s reagent
(b) Fehling’s solution
(c) Benedict solution
(d) All of these 

Question. 

Question. CH₃COCH₃ and CH₃CH₂CHO can be distinguished by
(a) FeCl₃
(b) Tollen’s reagent 
(c) NaHSO₃
(d) 2, 4-DNP     

Question. How will you convert butan-2-one to propanoic acid?
(a) Tollen’s reagent 
(b) Fehling’s solution
(c) NaOH/I₂/H⁺
(d) NaOH/ NaI/ H⁺     

Question. Acetone and acetaldehyde can be distinguished by
(a) Molisch test
(b) Tollen’s test 
(c) Schiffs test
(d) lodoform test