Question Set C

cbse 12th Standard Chemistry Amines Important Questions And Answers Study Material - QB365

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Questions:

Multiple Choice Question

50 x 1 = 50

Among the following which is the strongest base?

(a)

(b)

(c)

(d)

Auto-oxidation of chloroform in air and light produces a poisonous gas known as

(a)

phosphine

(b)

mustard gas

(c)

phosgene

(d)

tear gas

The correct name of the given reaction is \(\mathrm{Ar}-\mathrm{N}_2^{+} \mathrm{X}^{-} \xrightarrow{\mathrm{CuCN} / \mathrm{KCN}} \mathrm{Ar}-\mathrm{CN}+\mathrm{N}_2\)

(a)

Sandmeyer's reaction

(b)

Gabriel phthalimide synthesis

(c)

Carbylamine reaction

(d)

Hofmann bromamide degradation reaction

Which of the following reactions belong to electrophilic aromatic substitution?

(a)

Bromination of acetanilide

(b)

Coupling reaction of aryldiazonium salts

(c)

Diazotisation of aniline

(d)

Acylation of aniline

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)

Which of the following cannot be prepared by Sandmeyer's reaction?

(a)

Chlorobenzene

(b)

Bromobenzene

(c)

lodobenzene

(d)

Fluorobenzene

The order of basic strength of amines in aqueous solution is

(a)

(CH₃)₃N > (CH₃)₂NH > CH₃NH₂ > NH₃

(b)

CH₃NH₂ > (CH₃)₂ NH > (CH₃)₃ > H₃

(c)

NH₃ > (CH₃)₃N > (CH₃)₂NH > CH₃NH₂

(d)

(CH₃)₂NH > CH₃NH₂ > (CH₃)₃N > NH₃

(a)

(b)

(c)

(d)

10.

Which one of the following can be prepared by Gabriel phthalimide synthesis?

(a)

Aniline

(b)

o-Toluidine

(c)

Benzylamine

(d)

N-Methyl ethanamine

11.

Among (CH₃)₃N and CH₃CN, the electro negativity in the order

(a)

(b)

(c)

(d)

all have same

12.

(a)

(b)

(c)

(d)

13.

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

(a)

C₆H₆

(b)

C₆H₅CHO

(c)

C₆H₅NH₂

(d)

C₆H₅COOKI

14.

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

(a)

Aniline

(b)

Phenol

(c)

Anisole

(d)

Nitrobenzene

15.

Which of the following amine will form stable diazonium salt at 273-278K?

(a)

C₂H₅NH₂

(b)

C₆H₅NH₂

(c)

C₆H₅CH₂NH₂

(d)

C₆H₅N(CH₃)₂

16.

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

(a)

(b)

(c)

(d)

17.

-NH₂ group in the aniline is activating group and proceed reaction at

(a)

only para position

(b)

only ortho position

(c)

meta position

(d)

Both (a) and (b)

18.

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

19.

Choose the correct order of the boiling point of amines.

(a)

Primary> secondary> tertiary

(b)

Secondary > tertiary > primary

(c)

Tertiary>primary > secondary

(d)

Tertiary> secondary> primary

20.

IUPAC name of H₂N - CH₂ - CH₂ - NH₂ is

(a)

ethane-1, 3-diamine

(b)

ethane-1, 2-diarnine

(c)

ethyn-1 , 2, diamine

(d)

ethen-1, 2, diamine

21.

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)

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

22.

In the diazotisation of arylamine, the use of nitrous acid

(a)

suppresses hydrolysis of phenol

(b)

is a source of electropholic nitrosonium ion

(c)

neutralise the base liberated

(d)

all of the above

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.

Which of the following statements about primary amines is 'False' ?

(a)

Alkylamines are stronger base than ammonia.

(b)

Alkylamines are stronger bases than arylamines

(c)

Alkylamines react with nitrous acid to produce alcohols

(d)

Arylamines react with nitrous acid to produce pheols

25.

Which one of the following amines forms a non-acidic and alkali insoluble product with p-toluene sulphonyl chloride?

(a)

Tertiary butylamine

(b)

n-Butylamine

(c)

Isobutylamine

(d)

Diethylamine

(e)

N, N-Dimethylethylamine

26.

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

27.

On heating an aliphatic primary amine with chloroform and ethanolic potassium hydroxide, the organic compound formed is

(a)

alkyl isocyanide

(b)

an alkanol

(c)

an alkanediol

(d)

an alkyl cyanide

28.

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

29.

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

30.

Which of the following is the correct decreasing order of basicity os amines in gaseous phase?

(a)

(CH₃)₂NH > CH₃NH₂ > (CH₃)₃N > NH₃

(b)

(CH₃)₃N > (CH₃)₂NH > CH₃NH₂ > NH₃

(c)

(CH₃)₂NH > (CH₃)₃N > CH₃NH₂ > NH₃

(d)

(CH₃)₃N > CH₃NH₂ > (CH₃)₂NH > NH₃

31.

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

32.

Mendius reduction converts an alkyl cyanide to

(a)

a primary amine

(b)

an aldehyde

(c)

a ketone

(d)

an oxime

33.

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)

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

34.

Anorganic compound A upon reacting with NH₃ gives B. On heating, B gives C. C in presence of KOH reacts with Br₂ to give CH₃CH₂NH₂. A is

(a)

CH₃CH₂COOH

(b)

CH₃COOH

(c)

CH₃CH₂CH₂COOH

(d)

\({ CH }_{ 3 }-\underset { \underset { { CH }_{ 3 } }{ | } }{ CH } -COOH\)

35.

One of the followng amides will not undergo Hofmann bromamide reaction:

(a)

CH₃CONHCH₃

(b)

CH₃CH₂CONH₂

(c)

CH₂CONH₂

(d)

C₆H₅CONH₂

36.

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

37.

In the given set of reactions: \(2-Bromopropane\overset { alc.AgCN }{ \underset { heat }{ \longrightarrow } } X\overset { LiAIH_{ 4 } }{ \longrightarrow } Y\) . The IUPAC name of the product Y is

(a)

N-isopropylmethanamine

(b)

N-methylpropan-2-amine

(c)

N-methylpropanamine

(d)

butan-2-amine

38.

The electrolytic reduction of nitrobenzene in strongly acidic medium produces.

(a)

azobenzene

(b)

aniline

(c)

p-aminophenol

(d)

azoxybenzene

39.

Reduction of aromatic nitro compounds using Fe and HCI gives............................ .

(a)

aromatic oxime

(b)

aromatic hydrocarbon

(c)

aromatic primary amine

(d)

aromatic amide

40.

In the nitration of benzene using a mixture of conc. H₂SO₄ and conc.HNO₃, the species which initiates the reaction is......................... .

(a)

NO₂

(b)

NO⁺

(c)

\({ NO }_{ 2 }^{ + }\)

(d)

\({ NO }_{ 2 }^{ - }\)

41.

The best reagent for converting, 2-phenylpropanamide into 1-phenylethanamine is.................................. .

(a)

excess H₂/Pt

(b)

NaOH/Br₂

(c)

NaBH₄/methanol

(d)

LiAIH₄/ether

42.

Amongst the given set of reactants, the most appropriate for preparing \({2}^{ \circ }\) amine is............................. .

(a)

\({ 2 }^{ \circ }\) R-Br + NH₃

(b)

\({ 2 }^{ \circ }\) R-Br+NaCN followed by H₂/Pt

(c)

\({ 1 }^{ \circ }\) R-NH₂+RCHO followed by H₂/Pt

(d)

\({ 1 }^{ \circ }\) R-Br (2 mol) + potassium phthalimide followed by H₃O⁺/heat

43.

In order to prepare a \({ 1 }^{ \circ }\) amine from an alkyl halide with simultaneous addition of one -CH₂ group in the carbon chain, the reagent used as source of nitrogen is ___________ .

(a)

Sodium amide, NaNH₂

(b)

Sodium azide, NaN₃

(c)

Potassium cyanide, KCN

(d)

Potassium phthalimide, C₆H₆(CO)₂N^-K⁺

44.

Benzylamine may be alkylated as shown in the following equation:

C₆H₅CH₂NH₂+R-X \(\longrightarrow \) C₆H₅CH₂NHR

Which of the following alkyl halides is best suited for this reaction through S_N 1 mechanism?

(a)

CH₃Br

(b)

C₆H₅Br

(c)

C₆H₅CH₂Br

(d)

C₂H₅Br

45.

The correct IUPAC name for CH₂=CHCH₂NHCH₃ is

(a)

Allylmethylamine

(b)

2-amino-4-pentene

(c)

4-aminopent-1-ene

(d)

N-methylprop-2-en-1-amine

46.

In the following reaction, X is \(X\overset { Bromination }{ \longrightarrow } Y\overset { NaNO_{ 2 }\quad /HCI }{ \longrightarrow } Z\overset { Boiling }{ \underset { { C }_{ 2 }{ H }_{ 5 }OH }{ \longrightarrow } } Tribromobenzene\)

(a)

Benzoic acid

(b)

Salicylic acid

(c)

Phenol

(d)

Aniline

47.

When aniline is heated with conc.H₂SO₄ at 455-475 K, it forms:

(a)

Aniline hydrogen sulphate

(b)

m-Aminobenzensulphonic acid

(c)

Benzenesulphonic acid

(d)

Sulphanilic acid

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.

\({ CH }_{ 3 }{ CH }_{ 2 }\overset { Aq.KOH }{ \underset { \triangle }{ \longrightarrow } } A\overset { KMnO_{ 4 }\quad /\quad { H }^{ + } }{ \underset { \triangle }{ \longrightarrow } } B\overset { N{ H }_{ 3 } }{ \underset { \triangle }{ \longrightarrow } } C\overset { B{ r }_{ 2 } }{ \underset { Alkali }{ \longrightarrow } } D;D\quad is\)

(a)

\({ CH }_{ 3 }Br\)

(b)

\({ CH }_{ 3 }CONH_{ 2 }\)

(c)

\({ CH }_{ 3 }NH_{ 2 }\)

(d)

\({ CH }Br_{ 3 }\)

50.

C₆H₅CONHCH₃ can be converted into C₆H₅CH₂NHCH₃ by

(a)

NaBH₄

(b)

H₂-Pd/C

(c)

LIAIH₄

(d)

Zn-Hg/HCI

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Answers Key:

Multiple Choice Question

50 x 1 = 50

(a)
Sandmeyer's reaction

(a)
Bromination of acetanilide

(d)
(CH₃)₂NH > CH₃NH₂ > (CH₃)₃N > NH₃

10.

11.

12.

13.

(b)
C₆H₅CHO

14.

(d)
Nitrobenzene

15.

(b)
C₆H₅NH₂

16.

17.

(d)
Both (a) and (b)

18.

(b)
ROH

19.

(a)
Primary> secondary> tertiary

20.

(b)
ethane-1, 2-diarnine

21.

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

22.

(b)
is a source of electropholic nitrosonium ion

23.

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

24.

Arylamines react with NHO₂ to form diazonium salts.

25.

(d)
Diethylamine

26.

(a)
C₂H₅NC and 3 KCI

27.

In carbylamine reaction, alkyl isocyanides are formed.

28.

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.

29.

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

30.

In the gaseous phase, basicity increases as the +I effect of the alkyl groups increases. Thus, option (b) is correct.

31.

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.

32.

(a)
a primary amine

33.

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

34.

(a)
CH₃CH₂COOH

35.

Only \({ 1 }^{ \circ }\) amides undergo Hofmann bromamide reaction. CH₃CONHCH₃ being a \({ 2 }^{ \circ }\) amide a does not undergo this reaction.

36.

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.

37.

(b)
N-methylpropan-2-amine

38.

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

39.

40.

41.

(b)
NaOH/Br₂

42.

\(R-{ NH }_{ 2 }+RCHO\overset { Reductive }{ \underset { amination }{ \longrightarrow } } \quad \left[ R-N=CHR \right] \overset { { H }_{ 2 }/Pt }{ \longrightarrow } \underset { { 2 }^{ \circ }Amine }{ R-NH-{ CH }_{ 2 }R } \)

43.

44.

Since C₆H₅CH₂Br on ionization gives a resonance stabilized benzyl carbocation \(\left( { C }_{ 6 }{ H }_{ 5 }{ CH }_{ 2 }^{ + } \right) \) , therefore, C₆H₅CH₂Br is best suited for S_N1 reaction.

45.

\(\overset { 3 }{ C } { H }_{ 2 }=\overset { 2 }{ C } H\overset { 1 }{ C } { H }_{ 2 }NHCH_{ 3 }\quad N-Methylprop-2-en-1\quad amine\)

46.