Aldehydes Ketones and Carboxylic Acids Class 12 Chemistry MCQ Questions

Please refer to the MCQ Questions for Class 12 Chemistry Chapter 12 Aldehydes, Ketones and Carboxylic Acids with Answers. The following Aldehydes, Ketones and Carboxylic Acids Class 12 Chemistry MCQ Questions have been designed based on the latest syllabus and examination pattern for Class 12. Our experts have designed MCQ Questions for Class 12 Chemistry with Answers for all chapters in your NCERT Class 12 Chemistry book.

Aldehydes, Ketones and Carboxylic Acids Class 12 MCQ Questions with Answers

See below Aldehydes, Ketones and Carboxylic Acids Class 12 Chemistry MCQ Questions, solve the questions and compare your answers with the solutions provided below.

Question. The –OH group of an alcohol or the – COOH group
of a carboxylic acid can be replaced by – Cl using
(a) phosphorus pentachloride
(b) hypochlorous acid
(c) chlorine
(d) hydrochloric acid.

Answer

Question. Which one of the following orders of acid strength is correct?
(a) RCOOH > ROH > HOH > HC≡CH
(b) RCOOH > HOH > ROH > HC≡ CH
(c) RCOOH > HOH > HC≡ CH > ROH
(d) RCOOH > HC≡ CH > HOH > ROH

Answer

Question. Ethyl benzoate can be prepared from benzoic acid by using
(a) ethyl alcohol
(b) ethyl alcohol and dry HCl
(c) ethyl chloride
(d) sodium ethoxide.

Answer

Question. Reduction by LiAlH₄ of hydrolysed product of an ester gives
(a) two alcohols
(b) two aldehydes
(c) one acid and one alcohol
(d) two acids.

Answer

Question. Which one of the following compounds will react with NaHCO₃ solution to give sodium salt and carbon dioxide?
(a) Acetic acid
(b) n-Hexanol
(c) Phenol
(d) Both (b) and (c)

Answer

Question. An acyl halide is formed when PCl₅ reacts with an
(a) amide
(b) ester
(c) acid
(d) alcohol.

Answer

Question. Benzoic acid gives benzene on being heated with X and phenol gives benzene on being heated with Y. Therefore, X and Y are respectively
(a) soda-lime and copper
(b) Zn dust and NaOH
(c) Zn dust and soda-lime
(d) soda-lime and zinc dust.

Answer

Question. A is a lighter phenol and B is an aromatic carboxylic acid. Separation of a mixture of A and B can be carried out easily by using a solution of
(a) sodium hydroxide
(b) sodium sulphate
(c) calcium chloride
(d) sodium bicarbonate.

Answer

Question. The compound formed when malonic acid is heated with urea is
(a) cinnamic acid
(b) butyric acid
(c) barbituric acid
(d) crotonic acid.

Answer

Question. Among the following the strongest acid is
(a) CH₃COOH
(b) CH₂ClCH₂COOH
(c) CH₂ClCOOH
(d) CH₃CH₂COOH

Answer

Question. Which of the following is the correct decreasing order of acidic strength of (i) methanoic acid (ii) ethanoic acid (iii) propanoic acid (iv) butanoic acid
(a) (i) > (ii) > (iii) > (iv)
(b) (ii) > (iii) > (iv) > (i)
(c) (i) > (iv) > (iii) > (ii)
(d) (iv) > (i) > (iii) > (ii)

Answer

Question. Among the given compounds, the most susceptible to nucleophilic attack at the carbonyl group is
(a) CH₃COOCH₃
(b) CH₃CONH₂
(c) CH₃COOCOCH₃
(d) CH₃COCl

Answer

Question. The relative reactivities of acyl compounds towards nucleophilic substitution are in the order of
(a) acid anhydride > amide > ester > acyl chloride
(b) acyl chloride > ester > acid anhydride > amide
(c) acyl chloride > acid anhydride > ester > amide
(d) ester > acyl chloride > amide > acid anhydride.

Answer

Question. Consider the acidity of the carboxylic acids
I. PhCOOH
II. o-NO₂C₆H₄COOH
III. p-NO₂C₆H₄COOH
IV. m-NO₂C₆H₄COOH
Which of the following order is correct?
(a) I > II > III > IV
(b) II > IV > III > I
(c) Il > IV > I > III
(d) II > III> IV > I

Answer

Question. Which of the following is a better reducing agent for the following reduction?
RCOOH → RCH₂OH
(a) SnCL₂/HCl
(b) NaBH₄ /ether
(c) H₂ /Pd
(d) N₂H₄ / C₂H₅ONa
(e) B₂H₆ /ether

Answer

Question. Identify the organic compound which, on beating with strong solution of NaOH , partly converted into an, acid salt and partly into alcohol.
(a) Benzyl alcohol
(b) Acetaldehyde
(c) Acetone
(d) Benzaldehyde

Answer

Question. An important reaction of acetone is auto condensation in the presence of concentrated sulphuric acid to give the aromatic compund
(a) mesitylene
(b) mesityl oxide
(c) trioxan
(d) phorone

Answer

Question. End product of the following reaction is

MCQs For NCERT Class 12 Chemistry Chapter 12 Aldehydes, Ketones and Carboxylic Acids

Answer

Question. Which of the following represents the correct order of the activity in the given compounds?
(a) CH₃COOH> BrCH₂COOH> CICH₂COOH
>FCH₂COOH
(b) FCH₂COOH> CH₃COOH> BrCH₂COOH
> CICH₂COOH
(c) BrCHH₂COOH> CICH₂COOH> FCH₂COOH
>CH₃COOH
(d) FCH₂COOH> CICH₂COOH> BrCH₂COOH
>CH₃COOH

Answer

Question.

Answer

Question. In the reaction sequence,
A →^{CH₃CH₂MgBr} B →^H₃O⊕→C₅H₁₂O compound A is
(a) 1-propanol
(b) propanol-3
(c) ethanal
(d) 2-propanol

Answer

Question. Tollen’s reagent is
(a) [Ag(NH₃)₂ ]NO₃
(b) [Ag(NH₃)₂ ]Br
(c) Both (a) and (b)
(d) None of these

Answer

Question. A compound A has a molecular fommla C₂Cl₃OH. It reduces Fehling’s solution and on oxidation, gives a monocarboxylic acidB. A can be obtained by the action of chlorine on ethyl alcohol. A is
(a) chloroform
(b) chloral
(c) methyl chloride
(d) monochloroacetic acid

Answer

Question. An organic compound A upon reacting with NH₃ gives B. On heating, B gives C. C in the presence of KOH reacts with Br₂ to give CH₃CH₂NH₂ . A is
(a) CH₃COOH
(b) CH₃CH₂CH₂COOH
(c) CH₃—CH—COOH
l
CH₃
(d) CH₃CH₂COOH

Answer

Question. The acetophenone can be converted to etbylbenzene by reaction with
(a) LiAIH₄
(b) H₂NOH
(c) Pd / BaSO₄-H₂
(d) Zn-Hg / HCI

Answer

Question. The correct order of acidic strengths of the carboxylic acids is
(a) formic acid < benzoic acid < acetic acid
(b) formic acid < acetic acid < benzoic acid
(c) acetic acid < formic acid < benzoic acid
(d) acetic acid < benzoic acid < formic acid

Answer

Question. The compound K is

Answer

Question. Which of the following reagent is used to distinguish between methanoic acid and ethanoic acid
(a) Tollen’s reagent
(b) FeCl₃ solution
(c) NaOH solution
(d) Na₂CO₃ solution

Answer

Question. 3-hydroxybutanal is formed when (X) reacts with (Y) in dilute ( Z) solution. What are X, Y and Z?
X Y Z
(a) CH₃CHO, (CH₃)₂CO, NaOH
(b) CH₃CHO, CH₃CHO, NaCl
(c) (CH₃)₂CO, (CH₃)₂ CO, HCl
(d) CH₃CHO, CH₃CHO, NaOH

Answer

Question. Oxidation of which compound is not possible?
(a) CH₃—COOH
(b) CH₃—CO—CH₃
(c) CH₃—CHO
(d) CH₃—CH₂—OH

Answer

Question. Carboxylic acids readily dissolve in aqueous sodium bicarbonate, liberating carbon dioxide. Which one of the following is correct?
(a) Free carboxylic acid and its conjugate base are of comparable stability
(b) The free carboxylic acid is more stable than its conjugate base
(c) The conjugate base of the carboxylic acid is more stable than the free carboxylic acid
(d) The conjugate acid of the carboxylic acid is more stable than the free carboxylic acid

Answer

Question. Which of the following acid reduces Tollen’ reagent?
(a) Formic acid
(b) Acetic acid
(c) Lactic acid
(d) Oxalic acid

Answer

Question. What will be the end product (B) in the following sequence of reactions?

(a) 1, 2-dibromobenzene
(b) 1, 2-dibromobenzaldehyde
(c) 1, 3-dibromobenzene
(d) 1, 4-dibromobenzene

Answer

Question. The compound that does not liberate CO₂ on treatment with aqueous sodium bicarbonate solution is
(a) benzoic acid
(b) benzenesulphonic acid
(c) salicylic acid
(d) carbolic acid (Phenol)

Answer

Question. The gas evolved on heating alkali formate with sodaiime is
(a) CO
(b) CO₂
(c) hydrogen
(d) water vapour

Answer

Question.

Answer

Question. In the reaction, R—X →^{Alcoholic KCN} A →^{Dilute HCI} B The product B is
(a) alkyl chloride
(b) aldehyde
(c) carboxylic acid
(d) ketone

Answer

Question. The reaction, RCOOH + N₃H →^{Conc.II₂SO₄}
RNH₂ + CO₂ + N₂ is called
(a) Lossen reaction
(c) Curtius reaction
(b) Schmidt reaction
(d) Ullmann reaction

Answer

Question. Which of the following acids has the smallest dissociation constant ?
(a) CH₃CHFCOOH
(b) FCH₂CH₂COOH
(c) BrCH₂CH₂ COOH
(d) CH₃CHBrCOOH

Answer

Question. The compound formed when malonic acid is heated with urea is
(a) cinnamic acid
(b) butyric acid
(c) barbituric acid
(d) crotonic acid.

Answer

Question. Among the following the strongest acid is
(a) CH₃COOH
(b) CH₂ClCH₂COOH
(c) CH₂ClCOOH
(d) CH₃CH₂COOH

Answer

Question. Among the given compounds, the most susceptible to nucleophilic attack at the carbonyl group is
(a) CH₃COOCH₃
(b) CH₃CONH₂
(c) CH₃COOCOCH₃
(d) CH₃COCl

Answer

Question. The compound formed when malonic acid is heated with urea is
(a) cinnamic acid
(b) butyric acid
(c) barbituric acid
(d) crotonic acid.

Answer

Question. Among the following the strongest acid is
(a) CH₃COOH
(b) CH₂ClCH₂COOH
(c) CH₂ClCOOH
(d) CH₃CH₂COOH

Answer

Question. Among the given compounds, the most susceptible to nucleophilic attack at the carbonyl group is
(a) CH₃COOCH₃
(b) CH₃CONH₂
(c) CH₃COOCOCH₃
(d) CH₃COCl

Answer

Question. Self condensation of two moles of ethyl acetate in presence of sodium ethoxide yields
(a) ethyl propionate
(b) ethyl butyrate
(c) acetoacetic ester
(d) methyl acetoacetate

Answer

Question. Which one of the following esters cannot undergo Claisen self-condensation?
(a) C₆H₅CH₂COOC₂H₅
(b) C₆H₅COOC₂H₅
(c) CH₃CH₂CH₂CH₂COOC₂H₅
(d) C₆H₁₁CH₂COOC₂H₅