12. ALDEHYDES, KETONES AND CARBOXYLIC ACIDS Objective

12. ALDEHYDES, KETONES AND CARBOXYLIC ACIDS

1. Propanone can be prepared from ethyne by

(A) passing a mixture of ethyne and steam over a catalyst, magnesium at 420°C
(B) passing a mixture of ethyne and ethanol over a catalyst zinc chromite
(C) boiling ethyne with water in the presence of HgSO₄ and H₂SO₄
(D) treating ethyne with iodine and NaOH

2. The addition of HCN to carbonyl compounds is an example of

(A) nucleophilic addition
(B) electrophilic addition
(C) free radical addition
(D) electromeric addition

3. Aldehydes other than formaldehyde react with Grignard’s reagent to give addition products which on hydrolysis give

(A) tertiary alcohols
(B) secondary alcohols
(C) primary alcohols
(D) carboxylic acids

4. Which of the following will not give aldol condensation ?

(A) Phenyl acetaldehyde
(B) 2-Methylpentanal
(C) Benzaldehyde
(D) 1-Phenylpropanone

5. Identify reactant (X) in the given reaction sequence

CH₃COCH₃ + x → (CH₃)₃C – OMG – Cl  (CH₃)₃C – OH +

(A) CH₃MgCl
(B) CH₃COCl + Mg
(C) MgCl₂
(D) CH₃CH₂MgCl

6. α-Hydroxypropanoic acid can be preapred from ethanal by following the steps given in the sequence

(A) Treat with HCN followed by acidic hydrolysis
(B) Treat with NaHSO₃ followed by reaction with Na₂CO₃
(C) Treat with H₂SO₄ followed by hydrolysis
(D) Treat with K₂Cr₂O₇ in presence of sulphuric acid

7. What is the testto differentiate between penta-2-one and pentan-3-one ?

(A) Iodoform test
(B) Benedict’s test
(C) Fehling’s test
(D) Aldol condensation test

8. Study the given reaction and identify the process which is carried out

(A) It is used for purification of aldehydes and ketones
(B) It is used to distinguish aldehydes from ketones
(C) It is used to prepare cyclic aldehydes and ketones
(D) It is used to study polar nature of aldehydes and ketones

9. Hydrocarbons are formed when aldehydes and ketones are reacted with amalgamated zinc and conc. HCl. The reaction is called

(A) Cannizzaro reaction
(B) Clemmensen reduction
(C) Rosenmund reduction
(D) Wolff-Kishner reduction

10. The order of reactivity of CH₃CHO, CH₃COC₂H₅ and CH₃COCH₃ is

(A) CH₃CHO > CH₃COCH₃ > CH₃COC₂H₅
(B) C₂H₅COCH₃ > CH₃COCH₃ > CH₃CHO
(C) CH₃COCH₃ > CH₃CHO > C₂H₅COCH₃
(D) CH₃COCH₃ > C₂H₅COCH₃ > CH₃CHO

11. Which among the following is most reactive to give nucleophilic addition ?

(A) FCH₂CHO
(B) ClCH₂CHO
(C) BrCH₂CHO
(D) ICH₂CHO

12.

The product (X) will be

.     CH₂ONa
(A) |
.     COONa

.      COOH
(B) |
.     COOH

.     CH₂OH
(C) |
.    COONa

.      CH₂OH
(D) |
.     CH₂OH

13. Find the product of the given reaction

14. When propanal reacts with 2-methylpropanal in presence of NaOH, four different products are formed. The reaction is known as

(A) Aldol condensation
(B) Cross aldol condensation
(C) Cannizzaro reaction
(D) HVZ condensation

15. Which of the following IUPAC names is not correctly matched ?

(B) (CH₃)₂C = CHCOOH : 3-methylbut-2-enoic acid
(C) PhCH₂CH₂COOH : 3-Phenylpropanoic acid

16. The correct structure representation of carboxylate ion is

17. Identify (x) and (Y) in the given reaction sequence

18. Which of the following reactions does not occur ?

19. What are the correct steps to convert acetal-dehyde to acetone ?

(A) CH₃MgBr, H₂O, Oxidation
(B) Oxidation, Ca(OH)₂, Heat
(C) Reduction, KCN, Hydrolysis
(D) Oxidation, C₂H₅ONa, Heat

20. What happens when a carboxylic acid is treated with lithium aluminium hydride ?

(A) Aldehyde is formed
(B) Primary alcohol is formed
(C) Ketone is formed
(D) Grignard reagent is formed

21. Acetic acid can be halogenated in presence of phosphorous and chlorine. Formic acid cannot be halogenated with same way because of

(A) presence of α-H atom in formic acid
(B) presence of α-H atom in acetic acid
(C) absence of α-H atom in CH₃COOH
(D) higher acidic strength of acetic acid than formic acid

22. Which of the following is the correct order of relative strength of acids ?

(A) ClCH₂COOH > BrCH₂COOH > FCH₂COOH
(B) BrCH₂COOH > ClCH₂COOH > FCH₂COOH
(C) FCH₂COOH > ClCH₂COOH > BrCH₂COOH
(D) ClCH₂COOH > FCH₂COOH > BrCH₂COOH

23. The correct order of increasing acidic strength is

(A) phenol < ethanol < chloroacetic acid < acetic acid
(B) ethanol < phenol < chloroacetic acid < acetic acid
(C) ethanol < phenol < acetic acid < chloroacetic acid
(D) chloroacetic acid < acetic acid < phenol < ethanol

24. The reagent which does not react with both, acetone and benzaldehyde is

(A) Sodium hydrogensulphite
(B) Phenyl hydrazine
(C) Fehling’s solution
(D) Grignard reagent

25. CH₃ – C ≡ CH CH₃ – C – CH₃
.                                                                                          ||
.                                                                                           O

Structure of ‘A’ and type of isomerism in the above reaction are respectively
(A) prop-1-en-2-ol, metamerism
(B) prop-1-en-1-ol, tautomerism
(C) prop-2-en-2-ol, geometrical isomerism
(D) prop-1-en-2-ol, tautomerism

26. 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

27. In Clemmensen reduction carbonyl compound is treated with

(A) Zinc amalgam + HCI
(B) Sodium amalgam + HCI
(C) Zinc amalgam + nitric acid
(D) Sodium amalgam + HNO₃

28. Carbon atom in the carbonyl group is

(A) sp-hybridised
(B) sp²-hybridised
(C) sp3-hybridised
(D) dsp²-hybridised

29. The reaction is called

RCOCl + H₂ RCHO + HCl

(A) Cannizzaro reaction
(B) Rosenmund’s reaction
(C) Haloform reaction
(D) Clemensen’s reaction

30. Which of the following undergoes Cannizzaro’s reaction ?

(A) CH₃CHO
(B) CH₃CH₂CHO
(C) (CH₃)₂CHCHO
(D) HCHO

31. Paraldehyde is a trimer of

(A) Methanol
(B) Ethanol
(C) Butanol
(D) None

Class 12th Chemistry Objective Question English