CBSE Questions for Class 12 Medical Chemistry Aldehydes, Ketones And Carboxylic Acids Quiz 10 - MCQExams.com

In the above scheme of reactions, $$"X"$$ is ?
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A hydrocarbon $$(A)$$ has the molecular formula $$({C}_{8}{H}_{10})$$. (A) is oxidized by a strong oxidizing agent to (B). (B) on dehydration and subsequent reaction with ammonia forms an imide, (C). (C) is then reacted with a strong inorganic base to form a compound that undergoes Hoffman bromamide reaction to give (D). (D) is treated with sodium nitrite in an ice cold acidic solution to form the product (E). (E) is a steam volatile compound and on nitration gives two mononitro derivatives. (E) is treated with sodium hydroxide to form the salt (F). On heating a solution of (F), bubble are formed due to release of gas. This gas does not burn. On analysis it was found that the gas has two components, one lighter than air and one heavier than air.

Compound $$(B)$$ is :
  • Phthalic acid
  • Isophthalic acid
  • Terephthalic acid
  • Benzoic acid
Reagent (A) is :
250311.jpg
  • HBr
  • HBr + R O - O R + hv
  • HI
  • HCl + R O O R
For the following reaction, which of the following statements is correct?
249327_6abc586b84bf41ebb70e2b880f68f01b.png
  • Ring (A) is oxidised
  • Ring (B) is oxidised
  • Both are oxidised
  • None is oxidised
If (E) is reacted with acetaldehyde followed by acidification, product is.
  • acid
  • ketone
  • ether
  • alcohol
A carbonyl compound 'A' reacts with hydrogen cyanide to form a cyanohydrin 'B' which on hydrolysis gives an optically active alpha hydroxy acid 'C'. 'A' gives a positive iodoform test 'A', 'B' and 'C' are given by the set :-
2-methyl-1,3-cyclohexanedione is more acidic than cyclohexanone.
  • True
  • False
Which of the following compounds has very poor leaving group?
For the given reaction, which of these is correct?

263718_b2559235b7ec4876b291d5a3bd8939cb.png
  • $$L$$ must be better leaving group than $$Nu$$
  • $$Nu^-$$ must be strong enough nucleophile to attack carbonyl carbon
  • Carbonyl carbon must be enough electrophilic to react with $$Nu^-$$
  • All of these
Which of these statements are correct ?
  • Carbonyl compound is amphoteric in character
  • Acid catalyst makes the carbonyl carbon more electrophilic
  • basic catalyst makes the nucleophilic attack more faster.
  • All of these
Carbonyl compounds gives nucleophilic addtion with :
  • carbon nucleophile
  • oxygen nucleophile
  • Nitrogen nucleophile
  • All of these
Which of the statements are/is correct ? 
  • The rate determining step of addition reaction is the addition of nucleophile.
  • The rate-determining step is addition of electrophile.
  • The reaction intermediate of the reaction is alkoxide ion.
  • Both (A) and (C)
A carbonyl compound gives a positive iodoform test but does not reduce Tollen's reagent or Fehling's solution. It forms a cyanohydrin with HCN, which on hydrolysis gives a hydroxy acid with a methyl side chain. The compound is:
  • acetaldehyde
  • propionaldehyde
  • acetone
  • crotonaldehyde
Cyanohydrin of which of the following compound on hydrolysis gives optically active product?
  • HCHO
  • $$CH_3CHO$$
  • $$CH_3COCH_3$$
  • All the above
In this reaction: $$\displaystyle CH_{3}CHO+HCN \rightarrow CH_{3}CH(OH)CN \xrightarrow[] {H.OH}CH_{3}CH(OH)COOH$$, an asymmetric centre is generated. The acid obtained would be:
  • $$D$$ isomer
  • $$L$$ isomer
  • $$50\%$$ $$D$$ + $$50\%$$ $$L$$ isomer
  • $$20\%$$ $$D$$ + $$80\%$$ $$L$$ isomer
Carbonyl compounds show nucleophilic addition with :  
  • HCN
  • NaHSO$$_3$$
  • (CH$$_3$$OH + HCl)
  • all of these
Which among the following carbonyl compound is most polar ? 
Cyanogen $$(CN)_2$$ on hydrolysis yields:
  • malonic acid
  • maleic acid
  • formic acid
  • oxalic acid
In the reaction $$\text{X}$$ is:

274079_e75663f8b8404dc089ca051096645fa7.png
  • $$CH_3CH_2COOH$$
  • $$CH_3COOH$$
  • $$CH_3CH_2CHO$$
  • $$CH_3CH_2OH$$
Propanoic acid is obtained by the hydrolysis of:
  • ethyl cyanide
  • acetyl chloride
  • acetamide
  • all of the above
A carbonyl compound '$$A$$' reacts with hydrogen cyanide to form a cyanohydrin '$$B$$' which on hydrolysis gives an optically active alpha-hydroxy acid '$$C$$'. '$$C$$' also gives a positive iodoform test.
'$$A$$', '$$B$$' and '$$C$$' is given by the set:-
  • $$HCHO$$;
  • $$CH_{3}CHO$$;
  • $$CH_{3}CH_{2}CHO$$
Which of the following is most reactive to give nucleophilic addition ? 
  • FCH$$_2$$CHO
  • ClCH$$_2$$CHO
  • BrCH$$_2$$CHO
  • ICH$$_2$$CHO
Which of the following compound does not react with sodium bisulphite?
  • Benzaldehyde
  • Acetophenone
  • Acetone
  • Acetaldehyde
Select the correct statements.
332758_927fb9aca68f48028a17394cfac2092c.png
  • $$(Z)$$ has three carbonyl groups
  • Formation of $$(X)$$ involves equilibrium mixture of the iminium salt and the acylated enamine
In the given reaction, $$A$$ also reacts with $$NaOI$$ followed by the reaction with $$H^+$$ to give $$3,\,4-$$dilhydroxybenzoic acid. Which of the following is correct?

306083_fab8b1b3acdf499a826ddb0a7205830a.png
  • $$'C'$$ is optically active which is derived from $$A$$
  • No other side product is formed along with $$'A'$$
$$(D)+Benzaldehyde\;\xrightarrow[(ii)\;H_2O^+]{(i)\;Pyridine,\;\Delta}\;Major\;Product\,(E)$$
The major product $$(E)$$ is
  • Crotomic acid
  • Cinnamic acid
  • Benzoic acid
  • Mandelic acid
Which of the following acids does not contain $$-COOH$$ group?
  • Carbamic acid
  • Barbituric acid
  • Lactic acid
  • Succinic acid
The $$pK_{a}$$ values of four carboxylic acids are $$4.76, 4.19, 0.23$$ and $$3.41$$ respectively. The $$pK_{a}$$ value of strongest carboxylic acid among them is:
  • $$4.19$$
  • $$3.41$$
  • $$0.23$$
  • $$4.76$$
IUPAC name of the compound is:
591947.PNG
  • 3,4-Dihydroxybenzoic acid
  • 4,5-dihydroxybenzoic acid
  • 2,3-dihydroxybenzoic acid
  • none of these
$$R - CH_{2} - CH_{2} OH$$ can be converted into $$RCH_{2}CH_{2}COOH$$ by the following sequence of steps:
  • $$PBr_{3}, KCN, H_{2}/Pt$$
  • $$PBr_{3}, KCN, H_{3}O^{+}$$
  • $$HCN, PBr_{3}, H_{3}O^{+}$$
  • $$KCN, H_{3}O^{+}$$
Acetic acid is prepared from ________.
  • formaldehyde
  • acetaldehyde
  • vinyl acetate
  • all of the above
Benzene carbaldehyde is reacted with concentrated $$NaOH$$ solution to give the products $$A$$ and $$B$$. The product $$A$$ can be used as food preservative and the product $$B$$ is an aromatic hydroxy compound where $$OH$$ group is linked to $$sp^3$$ hybridised carbon atom next to benzene ring. The products $$A$$ and $$B$$ respectively are :
  • sodium benzoate and phenol
  • sodium benzoate and phenyl methanol
  • sodium benzoate and cresol
  • sodium benzoate and picric acid
Common name of 3-chloro, 2-butyric acid is:
  • $$\alpha $$ - chloro, $$\beta $$-methyl butyric acid
  • $$\beta $$ - chloro, $$\alpha $$-methyl butyric acid
  • $$\alpha $$,$$\beta $$ - chloro methyl butryic acid
  • none of the above
Amongst the following compounds, the one(s) which readily react with ethanolic $$KCN$$?
  • Ethyl chloride
  • Chloro benzene
  • Benzaldehyde
  • Salicylic acid
The boiling point of aldehyde and ketones depend upon:
  • intermolecular dipole-dipole repulsion
  • intermolecular dipole-dipole attraction.
  • intermolecular induced dipole-dipole attraction.
  • none of these.
Arrange the following compounds in the increasing order of their reactivity towards HCN.
I. Acetaldehyde
II. Acetone
III. Methyl-tert-butyl ketone
IV. Di-tert-butyl ketone
  • III < II < IV < I
  • II < I < IV < II
  • IV < III < II < I
  • II < IV < I < III
For the synthesis of benzoic acid, the only correct combination is:
  • (I) (iv) (Q)
  • (III) (iv) (R)
  • (IV) (ii) (P)
  • (II) (i) (S)
The only correct combination in which the reaction proceeds through radical mechanism is:
  • (III) (ii) (P)
  • (I) (ii) (R)
  • (IV) (i) (Q)
  • (II) (iii) (R)
n-butyl benzene on oxidation will give:
  • benzoic acid
  • butanoic acid
  • benzyl alcohol
  • benzaldehyde

The number of $$sp^2$$ hybridized carbon atoms in the given compound is:
631162_3f6f7acdb5b3462a9764b31af67c5496.png
  • 3
  • 4
  • 5
  • 6
In section A, there are some organic compounds and in section B, their uses are mentioned. Match the correct options.
Section A
Section B
Ethanol
(a) Nail polish remover
Formalin
(b) To have sour taste in food
Acetone
(c) In fragrant materials like perfumes
Ethanoic Acid
(d) To preserve dead bodies
  • (1-c), (2-d), (3-a), (4-b)
  • (1-a), (2-d), (3-c), (4-b)
  • (1-b), (2-a), (3-d), (4-c)
  • (1-d), (2-c), (3-b), (4-a)
The reaction of ethyl methyl ketone with $$Cl_2/$$ excess $$OH^-$$ gives the following major product.
  • $$ClCH_2CH_2COCH_3$$
  • $$CH_3CH_2COCCl_3$$
  • $$ClCH_2CH_2COCH_2Cl$$
  • $$CH_3CCl_2COCH_2Cl$$
4-nitrotoluene is treated with bromine to get compound '$$P$$' which is reduced with $$Sn$$ and $$HCl$$ to get compound '$$Q$$'. '$$Q$$' is diazotized and the product is treated with phosphinic acid to get compound '$$R$$'. '$$R$$' is oxidized with alkaline solution $$KMn{ O }_{ 4 }$$ to get the final product. Identify the final product.
  • 2-bromo-4-hydroxybenzoic acid
  • Benzoic acid
  • 4-bromobenzoic acid
  • 3-bromobenzoic acid
  • 2-bromobenzoic acid
A compound, containing only carbon, and hydrogen and oxygen, has a molecular weight ofOn complete oxidation it is converted into a compound of molecular weightThe original compound is:
  • an aldehyde
  • an acid
  • an alcohol
  • an ether
The compound formed as a result of oxidation of ethyl benzene by $$KMnO_{4}$$ is:
  • acetophenone
  • benzophenone
  • benzoic acid
  • benzaldehyde
Among the following compounds, the strongest acid is:
The major product formed in the given reaction is:
739797_aa69cc543e1d42059a0b1efc5b71de52.png
Which of the following is nucleophilic addition reaction?
  • Hydrolysis of ethyl chloride by $$NaOH$$
  • Purification of acetaldehyde by $$NaHS{ O }_{ 3 }$$
  • Alkylation of anisol
  • Decarboxlation of acetic acid
Polarisation of electrons in acrolein may be written as:
  • $$\overset{\delta +}{C}H_2=CH-CH=\overset{\delta -}{O}$$
  • $$\overset{\delta +}{C}H_2=\overset{\delta +}{C}H-CH={O}$$
  • $$\overset{\delta +}{C}H_2=CH-CH-\overset{\delta +}{OH}$$
  • $$\overset{\delta +}{C}H_3=CH-\overset{\delta +}{C}H={O}$$
In the reaction,
$$CH_{3} - CH = CH - CHO \underset {alkaline}{\xrightarrow {Oxidizing\  Agent}}CH_{3}- CH = CH - COOH$$, the oxidizing agent can be:
  • alkaline $$KMnO_{4}$$
  • acidified $$K_{2}Cr_{2}O_{7}$$
  • Benedict's solution
  • all of the above
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