Question Set C

cbse 12th Standard Chemistry Amines Model Questions Papers Study Material - QB365

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Questions:

Multiple Choice Question

50 x 1 = 50

Benzene diazonium chloride on hydrolysis gives.

(a)

Phenol

(b)

Chlorobenzene

(c)

Benzene

(d)

Aniline

Which of the following should be most volatile?
(I) CH₃CH₂CH₂NH₂
(II) (CH₃)₃N

(IV) CH₃CH₂CH₃

(a)

(b)

(c)

(d)

III

Among the following amines, the strongest Bronsted base is _____________

(a)

(b)

NH₃

(c)

(d)

Acid anhydrides on reaction with primary amines give ____________

(a)

amide

(b)

imide

(c)

secondary amine

(d)

imine

The most reactive amine towards dilute hydrochloric acid is ___________

(a)

CH₃ - NH₂

(b)

(c)

(d)

The product of the following reaction is ___________

(a)

(b)

(c)

(d)

4-Nitrotoluene is treated with bromine to get P. 'P' is reduced with Sn/HCI to get compound 'Q'. 'Q' is diazotised and the product is treated with phosphinic acid to get compound 'R'. 'R' is oxidised with alkaline KMnO₄ to get 'S'. Compound'S' is

(a)

2-Bromo-4-hydroxy benzoic acid

(b)

2-Bromo benzoic acid

(c)

3-Bromo benzoic acid

(d)

4-Bromo benzoic acid

\(^{\prime} \mathrm{A}^{\prime}\stackrel{\text { Reduction }}{\longrightarrow}{ }^{\prime} \mathrm{B}^{\prime} \stackrel{\mathrm{HNO}_{2}}{\longrightarrow} \mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH}\)
The compound' A' is

(a)

propane nitrile

(b)

ethane nitrile

(c)

nitro methane

(d)

methyl isocyanate

The reaction of P:Toluidine with CHCl₃ and KOH gives

(a)

(b)

(c)

(d)

10.

(a)

\(\beta\)-Alanine

(b)

\(\alpha\)-Alanine

(c)

Ethylene diamine

(d)

Oxamide

11.

In the reaction C₆H₅CONH₂ \(\xrightarrow[{\triangle }]{Br_2+KOH}\)Major product A is

(a)

C₆H₆

(b)

C₆H₅CHO

(c)

C₆H₅NH₂

(d)

C₆H₅COOKI

12.

The correct name for yellow dye is

(a)

p-hydroxy azobenzene

(b)

p-amino azobenzene

(c)

o-hydroxyazobenzene

(d)

o-amino azobenzene

13.

Which of the following compound will not undergo azo coupling reaction with benzene diazonium chloride?

(a)

Aniline

(b)

Phenol

(c)

Anisole

(d)

Nitrobenzene

14.

Benzene diazonium chloride when reacts with hypophosphorus acid produces

(a)

Benzene

(b)

Phenol

(c)

Phenol isocyanide

(d)

Phenyl phosphate

15.

Which of the following products is formed in the given reaction?

(a)

(b)

(c)

(d)

16.

Which of the following reactions is/are electrophilic substitution?

(a)

Bromination of aniline

(b)

Nitration of aniline

(c)

Sulphonation of aniline

(d)

All of the above

17.

Name the product(s) formed during the reaction of primary aliphatic amines with nitrous acid at room temperature?

(a)

\(\begin{equation} R \mathrm{~N}_{2}^{+} \mathrm{Cl^-} \end{equation}\)

(b)

ROH

(c)

Both (a) and (b)

(d)

None of the above

18.

Which of the following products is formed in the given reaction?

(a)

RNH₂

(b)

RCH₂NH₂

(c)

RCH₂CH₂NH₂

19.

p-Chloroaniline and anilinium hydrochloride can be distinguished by

(a)

Sandmeyer reaction

(b)

NaHCO₃ solution

(c)

AgNO₃ solution

(d)

Carbylamine reaction

20.

A positive carbylamine test is given by

(a)

N, N-dimethylaniline

(b)

2, 4-dimethylaniline

(c)

N-methyl-o-methylaniline

(d)

p-methylbenzylamine

21.

Reduction of benzenediazonium chloride with Zn/HCI hives

(a)

aniline

(b)

phenylhydrazine

(c)

azobenzene

(d)

hydrazobenzene

22.

Which of the following will be the most stable diazonium salt, \({ RN }_{ 2 }^{ + }{ X }^{ - }\) ?

(a)

\(CH_{ 3 }{ N }_{ 2 }^{ + }{ X }^{ - }\)

(b)

\({ C }_{ 6 }H_{ 5 }{ N }_{ 2 }^{ + }{ X }^{ - }\)

(c)

\(CH_{ 3 }{ CH }_{ 2 }{ N }_{ 2 }^{ + }{ X }^{ - }\)

(d)

\({ C }_{ 6 }H_{ 5 }{ CH }_{ 2 }{ N }_{ 2 }^{ + }{ X }^{ - }\)

23.

Which of the following diazonium salt is most stable?

(a)

p-Nitrobenzenediazonium chloride

(b)

2, 4-Dinitrobenzenediazonium chloride

(c)

2, 4, 6-Trinitrobenzenediazonium chloride

(d)

p-Methoxybenzenediazonium chloride

24.

During the preparation of arenediazonium salts, the excess of nitrous acid, if any, is destroyed by adding.

(a)

Aq.NaOH

(b)

Aq.Na₂CO₃

(c)

Aq.NH₂CONH₂

(d)

Aq.KI

25.

What reagent is used in Hinsberge test of amines?

(a)

(CH₃CO)₂O and pyridine

(b)

C₆H₅SO₂CI in aq.NaOH

(c)

NaNO₂ in aq.H₂SO₄

(d)

CH₃I (excess) followed by AgOH

26.

\({ C }_{ 6 }{ H }_{ 5 }COOH \ \overset { 1.{ NH }_{ 3 } }{ \underset { 2.\triangle }{ \longrightarrow } } P\overset { NaOBr }{ \longrightarrow } Q\quad \overset { 1. \ Conc.{ H }_{ 2 }{ SO }_{ 4 } }{ \underset { 2. \ heat\ \ to\ \ 460\ \ K }{ \longrightarrow } } \ \ \ \ R\) 'R' is

(a)

o-bromosulphanilic acid

(b)

sulphanilamide

(c)

sulphanilic acid

(d)

p-bromosulphanilamide

27.

Anilinium hydrogen sulphate on heating with sulphuric acid at 453-473 produces

(a)

benzenesulphonic acid

(b)

anthranilic acid

(c)

anline

(d)

m-aminobenzenesulphonic acid

(e)

sulphanilic acid

28.

Amino group is ortho-, para-directing for aromatic electrophilic substitution. On nitration of aniline, good amount of m-nitroaniline is obtained. This is due to

(a)

In nitration mixture, ortho, para-activity of NH₂ group is completely lost

(b)

-NH₂ becomes \(-{ NH }_{ 3 }^{ + }\), which is m-directing

(c)

-NH₂ becomes -NH+ \({ SO }_{ 4 }^{ - }\) , which is m-directing

(d)

-NH₂ becomes -NH^- \({ NO }_{ 2 }^{ + }\), which is m-directing

29.

Which gives black precipitate on reaction with CS₂ followed by addition of HgCl₂?

(a)

(CH₃)₃CNH₂

(b)

(C₂H₅)₂NH

(c)

(CH₃)₃N

(d)

all the three

30.

The compound which gives an oily nitrosoamine on reaction with nitrous acid at low temperature is

(a)

CH₃NH₂

(b)

(CH₃)₂CHNH₂

(c)

CH₃-NH-CH₃

(d)

(CH₃)₃N

31.

Positive carbylamine test is shown by

(a)

N, N-dimethylaniline

(b)

triethylamine

(c)

N-methylaniline

(d)

p-methylbenzylamine

(e)

dimethylamine

32.

In the chemical reaction, CH₃CH₂NH₂+CHCI₃+3 KOH \(\longrightarrow \) (A) + (B) + 3 H₂O. The compopund (A) and (B) are respectively.

(a)

C₂H₅NC and 3 KCI

(b)

C₂H₅CN and 3 KCI

(c)

CH₃CH₂CONH₂ and 3 KCI

(d)

C₂H₅NC and K₂CO₃

33.

A compound with molecular mass 180 is acylated with CH₃COCI to get a compound with molecular mass 390. The number of amino groups present per molecule of the former compound is

(a)

(b)

(c)

(d)

34.

The strongest base in aqueous solution among the following amines is

(a)

N, N-diethylethanamine

(b)

N-ethylethanamine

(c)

N-methylmethanamine

(d)

ethanamine

(e)

phenylmethanamine

35.

Considering the basic strength of amines in aqueous solution, which one has the smallest pK_b value?

(a)

C₆H₅NH₂

(b)

(CH₃)₂NH

(c)

CH₃NH₂

(d)

(CH₃)₃N

36.

Amongst the following amines, which one has the highest pK_b value in aqueous solution?

(a)

Methanamine

(b)

N, N-Dimethylaniline

(c)

Ethanamine

(d)

Benzenamine

(e)

N, N-Diethylethanamine

37.

Which of the following compounds is most basic?

(a)

Aniline

(b)

Cyclohexylamine

(c)

o-Nitroaniline

(d)

o-Toluidine

(e)

p-Methoxyaniline

38.

The correct order of basic strength of CH₃NH₂(I), (CH₃)₂NH(II), (CH₃)₃N(III), C₆H₅CH₂NH₂(IV) in gaseous phase is

(a)

IV < III < II < I

(b)

IV < III < I < II

(c)

I < II < III < IV

(d)

IV < I < II < III

39.

Mendius reduction converts an alkyl cyanide to

(a)

a primary amine

(b)

an aldehyde

(c)

a ketone

(d)

an oxime

40.

m-Bromoaniline can be prepared by

(a)

\({ C }_{ 6 }{ H }_{ 6 }\quad \overset { { HNO }_{ 3 } }{ \underset { { H }_{ 2 }{ SO }_{ 4 } }{ \longrightarrow } } \quad \overset { 1.Sn-HCI }{ \underset { { 2.NaOH,H }_{ 2 }O }{ \longrightarrow } } \quad \overset { { Br }_{ 2 } }{ \underset { H_{ 2 }O }{ \longrightarrow } } \)

(b)

\({ C }_{ 6 }{ H }_{ 6 }\ \overset { { Br }_{ 2 } }{ \underset { { FeBr }_{ 3 } }{ \longrightarrow } } \quad \overset { { HNO }_{ 3 } }{ \underset { H_{ 2 }{ SO }_{ 4 } }{ \longrightarrow } } \quad \overset { { H }_{ 2 } }{ \underset { Pt }{ \longrightarrow } } \)

(c)

\(m-Br{ C }_{ 6 }{ H }_{ 4 }COOH\ \overset{ SOCI_{ 2 } }{ \longrightarrow } \quad \overset { NH_{ 3 } }{ \longrightarrow } \quad \overset { Br_{ 2 },NaOH }{ \longrightarrow } \)

(d)

\({ C }_{ 6 }{ H }_{ 5 }{ NH }_{ 2 }\quad \overset { { NaNO }_{ 2 },HCI }{ \underset { { Cu }_{ 2 }Br_{ 2 } }{ \longrightarrow } } \overset { SOCI_{ 2 } }{ \longrightarrow } \quad \overset { NaNH_{ 2 } }{ \longrightarrow } \)

41.

Method by which aniline cannot be prepared is

(a)

degradation of benzamide with bromine in alkaline solution

(b)

reduction of nitrobenzene with H₂/Pd in ethanol

(c)

potassium salt of phthalimide treated with chlorobenzene followed by hydrolysis with aqueous NaOH solution.

(d)

hydrolysis of phenylisocyanide with acidic solution

42.

Which of the following compounds will not undergo Friedel-Crafts reaction easily?

(a)

Nitrobenzene

(b)

Toluene

(c)

Cumene

(d)

Xylene

43.

The electrolytic reduction of nitrobenzene in strongly acidic medium produces.

(a)

azobenzene

(b)

aniline

(c)

p-aminophenol

(d)

azoxybenzene

44.

Nitrobenzene on reaction with conc.HNO₃/H₂SO₄ at 80-\({ 100 }^{ \circ }\)C forms which one of the following products?

(a)

1, 4-Dinitrobenzene

(b)

1, 2, 4-Trinitrobenzene

(c)

1,2-Dinitrobenzene

(d)

1, 3-Dinitrobenzene

45.

Which of the following reagents would not be a good choice for reducing an aryl nitro compound to an amine?

(a)

H₂ (excess) / Pt

(b)

LiAIH₄ in ether

(c)

Fe and HCI

(d)

Sn and HCI

46.

Which of the following exists as a zwitterion?

(a)

p-Aminophenol

(b)

Salicylic acid

(c)

p-Aminophenol

(d)

Salicylic acid

47.

When ethylamine is treated with CH₃MgBr, the product is:

(a)

CH₃CH₃

(b)

CH₄

(c)

CH₃CH₂CH₃

(d)

CH₃CH₂CH₂CH₃

48.

Ethylamine on heating with CS₂ in presence of HgCl₂ forms

(a)

\({ C }_{ 2 }{ H }_{ 5 }NCS\)

(b)

\(\left( { C }_{ 2 }{ H }_{ 5 } \right) _{ 2 }S\)

(c)

\(\left( { C }_{ 2 }{ H }_{ 5 } \right) _{ 2 }CS\)

(d)

\({ C }_{ 2 }{ H }_{ 5 }\left( CS \right) _{ 2 }\)

49.

When a primary amine reacts with chloroform and ethanolic KOH, then the product formed is

(a)

isocyanide

(b)

aldehyde

(c)

cyanide

(d)

alcohol

50.

Which of the following is most basic?

(a)

Benzylamine

(b)

Aniline

(c)

Acetanilide

(d)

p-Nitroaniline

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Answers Key:

Multiple Choice Question

50 x 1 = 50

(a)
Phenol

(b)
IV

(a)
amide

(b)
2-Bromo benzoic acid

(b)
ethane nitrile

10.

(a)
\(\beta\)-Alanine

11.

(b)
C₆H₅CHO

12.

(b)
p-amino azobenzene

13.

(d)
Nitrobenzene

14.

(a)
Benzene

15.

16.

(d)
All of the above

17.

(b)
ROH

18.

(b)
RCH₂NH₂

19.

Both p-chloroaniline and anilinium hydrochloride are \({ 1 }^{ \circ }\) amines and hence cannot be ditinguished by carbylamine reaction.

20.

2, 4-Dimethylaniline and p-methylbenzylamine are \({ 1 }^{ \circ }\) amines and hence give positive carbylamine test.

21.

\({ C }_{ 6 }H_{ 5 }{ N }_{ 2 }CI\overset { Zn/HCI }{ \longrightarrow } { C }_{ 6 }H_{ 5 }{ NH }_{ 2 }+{ NH }_{ 3 }\)

22.

Due to delocalization of the +ve charge on the benzene ring, aromatic diazonium salts are more satble, i.e., option (b) is correct.

23.

Electron donating groups increase the stability of diazonium cations by dispersing the +ve charge on the N-atom.

24.

Urea decomposes \({ NH }_{ 2 }{ CONH }_{ 2 }\ +\ 2HONO\longrightarrow 2{ N }_{ 2 }\uparrow +{ CO }_{ 2 }\uparrow +3{ H }_{ 2 }O.\)

25.

(b)
C₆H₅SO₂CI in aq.NaOH

26.

27.

(e)
sulphanilic acid

28.

Protonation of the-NH₂ group gives NH₃ which is m-directing.

29.

Only \({ 1 }^{ \circ }\) amines undergo Hofmann Mustard oil reaction and thus give a black ppt. of HgS.

30.

\({ 2 }^{ \circ }\) Amines, i.e., (CH₃)₂NH, on treatment with HNO₂ give oily nitrosamines.

31.

Only \({ 1 }^{ \circ }\) amines, i.e., p-methylbenzylamine, (p) CH₃-C₆H₄-CH₂NH₂, give carbylamine test.

32.

(a)
C₂H₅NC and 3 KCI

33.

34.

Amines are stronger bases than amines followed by amines. Further, among amines, (C₂H₅)₂NH is more basic than (CH₃)₂NH due to stronger +I-effect of the CH₃CH₂ over CH₃ group. Thus, option (b) is correct.

35.

A strongest base has the smallest pK_b, i.e. option (b) is correct.

36.

All aliphatic amines are more basic than benzenamine. Further, due to the presence of two CH₃ groups on N in N, N-dimethylaniline, it is more basic than aniline or benzenamine. Hence, benzenamine is the weakest base base and hence has the highest pK_b value.

37.

Aliphatic/alicyclic amines are more basic than aromatic amines. Therefore, cyclohexylamine is most basic.

38.

In the gaseous phase, basicity increases as the + I-effect of the alkyl groups increases, i.e., CH₃NH₂(I) < (CH₃)₂ NH < (CH₃)₃ N (III). However, due to -I-effect of the CH- group, CHCHNH (IV) is even a weaker base than CHNH (I). Thus, the overall, basic character increases in the order : IV < I < II < III.

39.

(a)
a primary amine

40.

(c)
\(m-Br{ C }_{ 6 }{ H }_{ 4 }COOH\ \overset{ SOCI_{ 2 } }{ \longrightarrow } \quad \overset { NH_{ 3 } }{ \longrightarrow } \quad \overset { Br_{ 2 },NaOH }{ \longrightarrow } \)

41.

Aniline cannot be prepared by Gabriel phthalimide method because chlorobenzene (i.e.,aryl halide) does not undergo nucleophilic substitution reaction with potassium phthalimide in aqueous NaOH solution.

42.

-NO₂ is a powerful dectivating group. It reduces the electron density in the benzene ring considerably. As a result, it does not undergo F.C.reactions.

43.

Electrolytic reduction of nitrobenzene in strongly acidic medium gives p-aminophenol.

44.

-NO₂ is a m-directing group and hance 1, 3-dinitrobenzene is formed.

45.