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Questions:

Multiple Choice Question

96 x 1 = 96

Which one of the following is a cationic detergent ?

(a)

Sodium lauryl sulphate

(b)

Cetyltrimethylammonium bromide

(c)

Sodium dodecylbenzenesulphonate

(d)

Glyceryl palmitate

(e)

Glyceryl oleate

The sweetest artificial sugar among the following is

(a)

aspartane

(b)

sucrolose

(c)

alitame

(d)

sucrose

Use of chemicals for therapeutic effect is called

(a)

medicines

(b)

chemotheraphy

(c)

drug target interaction

(d)

phototheraphy

In DNA, the complimentary bases are

(a)

adenine and guanine ; thymine and cytosine

(b)

uracil and adenine ; cytosine and guanine

(c)

adenine and thymine ; guanine and cytosine

(d)

adenine and thymine ; guanine and uracil

The hormone which controls the processes of burning of fast, proteins and carbohydrates and liberates energy in the body is

(a)

thyroxine

(b)

adrenaline

(c)

insulin

(d)

cortisone

Compound which is added to soap to impart antiseptic properties is ............. .

(a)

sodium lauryl suphate

(b)

sodium dodecylbenzenesulphonate

(c)

rosin

(d)

bithional

Aniline is reacted with bromine water and the resulting product is treated with an aqueous solution of sodium nitrite in presence of dilute HCI. The compound so formed is converted into tetrafluoroborate which is subsequently heated dry. The final product is

(a)

p-bromofluorobenzene

(b)

p-bromoaniline

(c)

2, 4, 6-tribromofluorobenzene

(d)

1, 3, 5-tribromobenzene

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

Whaich of the following exist as zwitterion?

(a)

p-aminophenol

(b)

salicylic acid

(c)

sulphanilic acid

(d)

Ethanolamine

(e)

p-aminoacetophenon

10.

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)

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

11.

Glucose molecule reacts with X number of molecules of phenydrazine to yield osazone. The value of X is

(a)

three

(b)

two

(c)

one

(d)

four

12.

Which of the following are biodegradable polymers?

(a)

Nylon-6,6

(b)

PHBV

(c)

Nylon-2-Nylon-6

(d)

Polychloroprene

13.

Terylene is a condensation polymer of ethylene glycol and

(a)

benzoic acid

(b)

phthalic acid

(c)

salicylic acid

(d)

terephthalic acid

14.

The species which can best serve as an initiator for the cationic polymerization is

(a)

HNO₃

(b)

AlCl₃

(c)

BuLi

(d)

LiAlH₄

15.

Which of the following is a chain growth polymer?

(a)

Starch

(b)

Nucleic acid

(c)

Polystyrene

(d)

Proteiuns

16.

Pick out the correct statements from the following
1. Cobalt (III) is more stable in octahedral complexes.
2. Zinc forms coloured ions or complexes.
3. Most of the d - block elements and their compounds are ferromagnetic.
4. Osmium shows (VIII) oxidation state.
5. Cobalt (II) is more stable in octahedral complexes.

(a)

1 and 2

(b)

1 and 3

(c)

2 and 4

(d)

1 and 4

(e)

2 and 5

17.

In context of the lanthanoids, which of the following statements is not correct ?

(a)

All the members exhibit +3 oxidation state

(b)

Because of similar properties, the separation of lanthanoids is not easy.

(c)

Availability of 4f electrons results in the formation of compounds in +4 state for all the members of series.

(d)

There is a gradual decrease in the radii of the members with increasing atomic number in the series.

18.

Which of the following are examples of synthetic rubber?

(a)

Polychloroprene

(b)

Polyacrylonitrile

(c)

Buna-N

(d)

cis-Polyisoprene

19.

Which of the following monomers form biodegradable polymers?

(a)

3-hydroxybutanoic acid + 3-hydroxypentanoic acid

(b)

Glycine + \(\epsilon\)-aminocaproic acid

(c)

Ethylene glycol + phthalic acid

(d)

Caprolactum

20.

A student accidently added conc . H₂SO₄ to potassium permanganate and it exploded due to the formation of an explosive which is

(a)

MnO

(b)

Mn₂O₃

(c)

Mn₂O₅

(d)

Mn₂O₇

21.

Which of the following statements is not true about low density polythene?

(a)

Tough

(b)

Hard

(c)

Poor conductor of electricity

(d)

Highly branched structure

22.

Which of the following polymers of the glucose is stored by animals?

Cellulose Amylose Amylopectin Glycogen

(a)

Cellulose

(b)

Amylose

(c)

Amylopectin

(d)

Glycogen

23.

Among the following pairs of ions, the lower oxidation state in aqueous solution is more stable than the other, in

(a)

Ti⁺,Ti³⁺

(b)

Cu⁺,Cu²⁺

(c)

Cr²⁺,Cr³⁺

(d)

V²⁺,VO²⁺

24.

Amoung the following compounds. most acidic is

(a)

p-nitrophenol

(b)

p-hydroxybenzoic acid

(c)

o-hydroxybenzoic acid

(d)

p-toluic acid

25.

Reaction of Carbonyl compound with one of the following reagents involves nucleophilic addition followed by elemination of water. The reagent is

(a)

hydrazine in presence of feelby acidic solution

(b)

hydrocyanic acid

(c)

sodium hydrogen sulphite

(d)

Grignard reagent

26.

Among the following sets of reactants which one produces anisole?

(a)

CH₃CHO; RMgX

(b)

C₆H₅OH; CH₃I

(c)

C₆H₅OH; neutral FeCl₃

(d)

C₆H₅CH₃; CH₃COCl; AlCl₃

27.

Ortho-nitrophenol is less soluble in water than p-and m-nitrophenols because

(a)

o-nitrophenol shows intramolecular H-bonding

(b)

o-nitrophenol shows intramolecular H-bonding

(c)

melting point of o-nitrophenols is lower than those of m- and p-nitrophenol

(d)

o-nitrophenol is more volatile in steam than those of m- and p-isomers

28.

Which of the following antacids is an antihistamine ?

(a)

Ranitidine

(b)

Lansoprazole

(c)

Terfenadine

(d)

Luminal

29.

Isopropyl benzene is oxidised in the presence of air to compound 'A'. When compound 'A' is treated with dilute mineral acid,the aromatic product formed is

(a)

phenol

(b)

benzene

(c)

benzaldehyde

(d)

acetophenone

(e)

toluene

30.

Which of the following is a step-growth polymer?

(a)

Polyacrylonitrile

(b)

Polyisoprene

(c)

Nylon

(d)

Polythene

31.

Which of the following is a branched polymer?

(a)

Low density polythene

(b)

Polyester

(c)

Nylon

(d)

PVC

32.

The number of chiral carbons in \(\beta \) -D (+)- glucose is

(a)

five

(b)

six

(c)

three

(d)

four

33.

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)

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

34.

Which of the following is the industrial method of preparation of acetaldeyde ?

(a)

CH3CN \(\xrightarrow [ HCI ]{ Sn{ CI }_{ 2 } } \) CH3CH = NH \(\xrightarrow {H_3O^{+}}\)

(b)

CH3COCI + H2 \(\xrightarrow [ BaSO_4 ]{Pd } \) CH3CHO + HCI

(c)

CH2 = CH2 + H2O \(\xrightarrow {Pd ^{2+}}\)

(d)

All of the above.

35.

Phenylmagnesium bromide reacts with methanol to give

(a)

a mixture of anisole and Mg(OH)Br

(b)

a mixture of benzene and Mg(OMe)Br

(c)

a mixture of toluene and Mh(OH)Br

(d)

a mixture of phenol and Mg(OH)Br

36.

Which among the following compounds will give a secondary alcohol on reacting with Grignard reagent followed by acid hydrolysis?
I. HCHO
II. C₂H₅CHO
III. CH₃COCH₃ IV.RCOOC₂H₅
Select the correct answer using the code given below:

(a)

Only II

(b)

Only III

(c)

II and IV

(d)

III and IV

37.

Consider the following reaction, ethanol \(\overset{PCl_5}\longrightarrow\) X \(\overset{alc.KOH}\longrightarrow\) Y \(\overset{H_2SO_4}{\underset {(ii)H_2O,room temperature}{\longrightarrow}}\) Z The product Z is:

(a)

CH₃CH₂- O - CH₂CH₃

(b)

CH₃CH₂- O-SO₃H

(c)

CH₃CH₂OH

(d)

CH₂= CH₂

38.

When propionic acid is treated with aqueous sodium bicarbonate, CO₂ is liberated. The 'C' of CO₂ comes from

(a)

methyl group

(b)

carboxylic acid group

(c)

methylene group

(d)

bicarbonate

39.

The product formed in Aldol condensation is

(a)

an alpha, beta unsaturated ester

(b)

a beta hydroxy acid

(c)

a beta hydroxyaldehyde or ketone

(d)

an alpha hydroxy aldehyde or ketone

40.

Out of the following the alkene that exhibits optical isomerism is

(a)

3-methyl-1-pentene

(b)

2-methyl-2-pentene

(c)

3-methyl-2-pentene

(d)

4-methyl-1-pentene

41.

KMnO₄ acts as an oxidising agent in acidic medium. The number of moles of KMnO₄ that will be needed to react with one mole of sulphide ions in acidic solution is

(a)

\(\frac { 2 }{ 5 } \)

(b)

\(\frac { 3 }{ 5 } \)

(c)

\(\frac { 4 }{ 5 } \)

(d)

\(\frac { 1 }{ 5 } \)

42.

Alkyl halides are prepared from alcohols by treating with

(a)

HCl+ZnCl₂

(b)

Red P+Br₂

(c)

H₂SO₄+KI

(d)

All the above

43.

The compounds [Co(SO₄)(NH₃)₅]Br and [Co(SO₄)(NH₃)]Cl represent

(a)

Linkage isomerism

(b)

ionisation isomerism

(c)

Coordination isomerism

(d)

no isomerism

44.

The compound,

C₇H₈ \(\xrightarrow { 3{ CI }_{ 2 }/\triangle } A\xrightarrow { Br_{ 2 }/Fe } B\xrightarrow { Zn/HCI } C\)

The compound C is

(a)

o-Bromotoluene

(b)

m-Bromotoluene

(c)

p-Bromotoluene

(d)

3-Bromo-2,4,6-trichlorotoluene

45.

Best reagent for nuclear iodination of aromatic compounds is

(a)

KI/CH₃COCH₃

(b)

I₂/CH₃CN

(c)

KI/CH₃COOH

(d)

I₂/HNO₃

46.

If I₂ is dissolved in aqueous KI, the intense yellow species, I\(\overset{-}{3}\) is formed. The structure of I\(\overset{-}{3}\) ion is

(a)

square pyramidal

(b)

trigonal bipyramidal

(c)

octahedral

(d)

pentagonal bipyramidal

47.

CH₃OC₂H₅ and (CH₃)₃ COCH₃ are treated with hydriodic acid. The fragments after reactions obtaind are:

(a)

CH₃I+HOC₂H₅ ; (CH₃)₃C-I+HOCH₃

(b)

CH₃HO+C₂H₅I; (CH₃)₃C-I+HOCH₃

(c)

CH₃OH+C₂H₅I; (CH₃)₃C-OH+CH₃I

(d)

CH₃I+HOC₂H₅; CH₃I+(CH₃)₃C-O H

48.

Products obtained when HI reacts with isopropyl methyl ether at 373 K are

(a)

isopropyl iodide and methyl alcihol

(b)

isopropyl alcohol and methyl iodide

(c)

isopropyl iodide and water

(d)

methyl iodide and water

49.

CuCl is insoluble in water but it dissolves in KCl solution. This is due to the formation of the complex

(a)

K₂[CuCl₃]

(b)

K₃[CuCl₄]

(c)

K[CuCl₂]

(d)

All of these

50.

In which of the following arrangements, the given sequence is not strictly according to the property indicated against it ?

(a)

HF<HCl<HBr<HI : increasing acid strength

(b)

H₂O<H₂S<H₂Se<H₂Te : increasing pK_a values

(c)

NH₃<PH₃<AsH₃<SbH₃ : increasing acidic character

(d)

CO₂<SiO₂<SnO₂<PbO₂ : increasing oxidising power

51.

Phenol can be distinguished from ethanol by the following reagents except

(a)

sodium

(b)

NaOH/I₂

(c)

neutral FeCl₃

(d)

Br₂/H₂O

52.

The compound (C) in the following series of reactions is:
\(Aceton+{ CH }_{ 3 }MgBr\overset { Dry\ ether }{ \longrightarrow } A\overset { { H }_{ 3 }{ O }^{ + } }{ \longrightarrow } B\overset { 363K }{ \underset { 20%{ H }_{ 2 }{ SO }_{ 4 } }{ \longrightarrow } } C+H_{ 2 }O\)

(a)

2-Methylpropene

(b)

but-2-ene

(c)

but-1-ene

(d)

propene

53.

The Gibbs energy for the decomposition of Al₂O₃ at 500°C is as follows :
\(\frac { 2 }{ 3 } { Al }_{ 2 }{ O }_{ 3 }\longrightarrow \frac { 4 }{ 3 } Al+{ O }_{ 2 },{ \Delta }_{ r }G=+966 \ kJ \ { mol }^{ -1 }\)
The potential difference needed for electrolytic reduction of Al₂O₃ at 500°C is at least

(a)

2.5 V

(b)

5.0 V

(c)

4.5 V

(d)

3.0 V

54.

Given the data at 25°C,
\(Ag+{ I }^{ - }\longrightarrow AgI+{ e }^{ - };{ E }^{ 0 }=0.152V\)
\(Ag\longrightarrow { Ag }^{ + }+{ e }^{ - };{ E }^{ 0 }=-0.800V\)
What is the value of log K_sp for AgI ? (2.303 RT/F = 0.059 V)

(a)

- 37.83

(b)

- 16.13

(c)

- 8.12

(d)

+ 8.612

55.

A lead storage battery has been used for one month (30 days) at the rate of one hour per day by drawing a constant current of 2 amperes. H₂SO₄ consumed by the battery is

(a)

1.12 mole

(b)

2.24 mole

(c)

3.36 mole

(d)

4.48 mole

56.

For the half-cell reaction, \(2{ H }_{ 2 }O+{ 2e }^{ - }\longrightarrow { H }_{ 2 }+2{ OH }^{ - },{ E }^{ 0 }=-0.8277V\) at 298 K. Autoprotolysis constant of water calculated from this value will be

(a)

1 x 10^-10

(b)

1 x 10^-12

(c)

1 x 10^-13

(d)

1 x 10^-14

57.

Which of the following is diamagnetic in nature?

(a)

Co³⁺, octahedral complex with weak field ligands

(b)

Co³⁺, octahedral complex with strong field ligands

(c)

Co²⁺ in tetrahedral complex

(d)

Co²⁺ in square planar complex

58.

Nitrogen dioxide and sulphur dioxide have some properties in common. Which property is shown by one of these compounds, but not by the other?

(a)

Is soluble in water

(b)

Is used as a food preservatives

(c)

Forms 'acid rain'

(d)

Is a reducing agent

59.

Cryolite is

(a)

Na₃AlF₆ and is used in the electrolysis of alumina for lowering the melting point of alumina only

(b)

Na₃AlF₆ and is used in the electrolytic refining of alumina

(c)

Na₃AlF₆ and is used in the electrolysis of alumina for decreasing electrical conductivity

(d)

Na₃AlF₆ and is used in the electrolysis of alumina for lowering the melting point and increasing the conductivity of alumina

60.

Nitric acid can be obtained from ammonia via the formation of the intermediate compounds

(a)

nitric oxide and nitrogen dioxide

(b)

nitrogen and nitric oxide

(c)

nitric oxide and dinitrogen pentoxide

(d)

nitrogen and nitrous oxide

61.

The orange solid on heating gives a colourless gas and a green solid which cab be reduced to metal by aluminum powder. The orange and the green solids are, respectively,

(a)

(NH₄)₂Cr₂O₇ and Cr₂O₃

(b)

Na₂Cr₂O₇ and Cr₂O₃

(c)

K₂Cr₂O₇ and CrO₃

(d)

(NH₄)₂CrO₄ and CrO₃

62.

Which of the following statements are correct concerning redox properties ?
(i) A metal M for which E⁰ for the half life reaction \({ M }^{ n+ }+{ ne }^{ - }\rightleftharpoons M\) is very negative will be a good reducing agent.
(ii) The oxidizing power of the halogen decreases from chlorine to iodine
(iii) The reducing power of hydrogen halides increases from hydrogen chloride to hydrogen iodide

(a)

(i), (ii) and (iii)

(b)

(i) and (ii)

(c)

(i) only

(d)

(ii) and (iii) only

(e)

(iii) only

63.

Which of the following reaction is an example of calcination process?

(a)

2Ag + 2HCl + [O]\(\longrightarrow\)2AgCl + H₂O

(b)

2Zn + O₂\(\longrightarrow\) 2ZnO

(c)

2ZnS + 3O₂\(\longrightarrow\) 2ZnO + 2SO₂

(d)

MgCO₃\(\longrightarrow\) MgO + CO

64.

Addition of HBr gives same product in the presence or absence of peroxide when alkene is

(a)

1-butene

(b)

2-methylpropene

(c)

propene

(d)

2-butene

65.

In which of the following reactions, conc. H₂SO₄ is used as an oxidising reagent?

(a)

CaF₂ + H₂SO₄\(\rightarrow\)CaSO₄ + 2HF

(b)

2HI + H₂SO4 \(\rightarrow\) I₂ + SO₂ + 2H₂O

(c)

Cu + 2H₂SO₄ \(\rightarrow\) CuSO₄ + SO₂ + 2H₂O

(d)

NaCl + H₂SO₄ \(\rightarrow\) NaHSO₄ + HCl

66.

\({ Ag }^{ + }+{ NH }_{ 3 }\rightleftharpoons \left[ Ag\left( { NH }_{ 3 } \right) \right] ^{ + }\) ; K₁= 6.8 x 10^-3
\(\left[ Ag\left( { NH }_{ 3 } \right) \right] ^{ + }+{ NH }_{ 3 }\rightleftharpoons \left[ Ag\left( { NH }_{ 3 } \right) _{ 2 } \right] ^{ + }\)
then the formation constant of [Ag(NH₃)₂]⁺ is

(a)

\(1.08\times { 10 }^{ -7 }\)

(b)

\(1.08\times { 10 }^{ -5 }\)

(c)

\(1.08\times { 10 }^{ -9 }\)

(d)

none of these

67.

For an endothermic reaction, where \(\triangle H\) represents the enthalpy of the reaction in kJ/mol. The minimum value for the energy of activation will be

(a)

less than \(\triangle H\)

(b)

zero

(c)

more than \(\triangle H\)

(d)

equal to \(\triangle H\)

68.

Hot conc. H₂SO₄ acts as moderately strong oxidising agent. It oxidises both metals and nonmetals. Which of the following element is oxidised by conc. H₂SO₄ into two gaseous products?

(a)

(b)

(c)

(d)

69.

On heating ammonium dichromate and barium azide separately we get

(a)

N₂in both cases

(b)

N₂with ammonium dichromate and NO with barium azide

(c)

N₂O with ammonium dichromate and N₂with barium azide.

(d)

N₂O with ammonium dichromate and NO₂with barium azide.

70.

Under the same reaction conditions, initial concentration of 1.386 mol dm^-3 of a substance becomes half in 40 seconds and 20 seconds through first order and zero kinetices respectively. Ratio (k₁/k₀) of the rate constants for first order (k₁) and zero order (k₀) of the reactions is

(a)

0.5 mol^-1dm³

(b)

1.0 mol^-1 dm^-3

(c)

1.5 mol^-1 dm^-3

(d)

2.0 mol^-1 dm³

71.

At 500 K, the half-life period of a gaseous reaction at the initial pressure of 80 kPa is 350 sec. When the pressure is 40 kPa, the half-life period is 175 sec. The order of reaction is

(a)

second

(b)

more than zero but less than first

(c)

zero

(d)

first

72.

The rate constant of a second order reaction, 2A\(\longrightarrow\) Products, is 10^-4 lit mol^-1 min^-1. The initial concentration of the reactant is 10^-2mol lit^-1. What is the half-life (in min) ?

(a)

(b)

1000

(c)

100

(d)

10⁶

73.

Half -lives of a first order and a zero order reaction are same. Then the ratio of the initial rates of the first order reaction to that of zero order reaction is

(a)

\(\frac {1}{0.693}\)

(b)

2\(\times\) 0.693

(c)

0.693

(d)

\(\frac {2 }{0.693}\)

74.

In the synthesis of ammonia from nitrogen and hydrogen gases, if 6\(\times 10 ^{-2 }\) mole of hydrogen disappears in 10 minutes, the number of moles of ammonia formed in 0.3 minutes is

(a)

1.8\(\times 10 ^{-2 }\)

(b)

1.2\(\times 10 ^{-2 }\)

(c)

4\(\times 10 ^{-2 }\)

(d)

3.6\(\times 10 ^{-2 }\)

75.

Which of the following reactions occur during calcination?

(a)

CaCO₃\(\longrightarrow\)CaO+CO₂

(b)

2FeS₂+\(1\over2\)O₂\(\longrightarrow\)Fe₂O₃+4SO₂

(c)

Al₂O₃.xH₂O\(\longrightarrow\)Al₂O₃+xH₂O

(d)

ZnS+\(3\over2\)O₂\(\longrightarrow\)ZnO+SO₂

76.

Which of the following is not a favourable condition for physical adsorption?

(a)

high pressure

(b)

negative \(\triangle H\)

(c)

higher critical temperature of adsorbate

(d)

high temperature

77.

Which property of colloidal solution is independent of charge on the colloidal particles ?

(a)

Electro - osmosis

(b)

Tyndall effect

(c)

Coagulation

(d)

Electrophoresis

78.

The method of zone refining of metals is based on the principle of

(a)

greater mobility of the pure metal than that of the impurity

(b)

higher melting point of the impurity than that of the pure metal

(c)

greater noble character of the solid metal than that of the impurity

(d)

greater solubility of the impurity in the molten state than the solid

79.

Which one of the following arrangements represents the correct order of electron gain enthalpy (with negative sign) of the given atomic species?

(a)

F<Cl<O<S

(b)

S<O<Cl>F

(c)

O<S<F<Cl

(d)

Cl<F<S<O

80.

For H₃PO₃ and H₃PO₄, the correct choice is

(a)

H₃PO₃is dibasic and reducing

(b)

H₃PO₄is dibasic and non-reducing

(c)

H₃PO₄is tribasic and reducing

(d)

H₃PO₃is tribasic and non-reducing

81.

Adsorption is accompanied by

(a)

decrease in enthalpy and increase in entropy

(b)

increase in enthalpy and increase in entropy

(c)

decrease in enthalpy and decrease in entropy

(d)

no change in enthalpy and entropy

82.

The emulsifying agent present in milk that makes it stable is

(a)

lactose

(b)

maltose

(c)

casein

(d)

lactic bacilli

83.

Rate law cannot be determined from balanced chemical equation if ........ .

(a)

reverse reaction is involved

(b)

it is an elementary reaction

(c)

it is a sequence of elementary reactions

(d)

any of the reactants is in excess.

84.

Which of the following statements is not correct about order of a reaction ?

(a)

The order of a reaction can be a fractional number

(b)

Order of a reaction is experimentally determined quantity.

(c)

The order of a reaction is always equal to the sum of the stoichiometric coeffecients of reactants in the balanced chemnical equation for reaction.

(d)

The order of a reaction is the sum of the powers of molar concentration of the reaction in the rate law expression.

85.

A solution containing 0.10 g of non - volatile solute X (molar mass : 100) in 200 g of benzene depresses the freezing point of benzene by 0.25^oC while 0.50g of another non - volatile solute Y in 100 g of benzene also depresses by 0.25^oC. What is the molecular mass of Y ?

(a)

(b)

100

(c)

150

(d)

1000

86.

Consider a first order gas phase decomposition reaction given below : A(g) \(\longrightarrow\) B(g) + C(g) The initial pressure of the system before decomposition of A was pi . After lapse of time 't' , total pressure of the system increased by x the reaction is given as ............... .

(a)

k = \(\frac {2.303}{t} log \frac {p_i}{p_i - x}\)

(b)

k = \(\frac {2.303}{t} log \frac {p_i}{2p_i - p_i}\)

(c)

k = \(\frac {2.303}{t} log \frac {p_i}{2p_i + p_i}\)

(d)

k = \(\frac {2.303}{t} log \frac {p_i}{p_i +x}\)

87.

\(6.02\times { 10 }^{ 20 }\) molecules of urea are present in 100 mL of its solution. The concentration of the solution is

(a)

0.02 M

(b)

0.01 M

(c)

0.001 M

(d)

0.1 M

88.

In the reaction BrO^-₃ (aq) + 5 Br ^- (aq) + 6 H⁺ \(\longrightarrow\) 3 Br₂(I) + 3 H₂O (l), the rate of apperance of bromine (BHr₂) is related to the disapearance of bromide uions as follows :

(a)

\(\frac { d[{ Br }_{ 2 }] }{ dt } =-\frac { 5 }{ 3 } \frac { d[{ Br }^{ - }] }{ dt } \)

(b)

\(\frac { d[{ Br }_{ 2 }] }{ dt } =\frac { 5 }{ 3 } \frac { d[{ Br }^{ - }] }{ dt } \)

(c)

\(\frac { d[{ Br }_{ 2 }] }{ dt } =\frac {3 }{ 5} \frac { d[{ Br }^{ - }] }{ dt } \)

(d)

\(\frac { d[{ Br }_{ 2 }] }{ dt } =-\frac { 3 }{ 5 } \frac { d[{ Br }^{ - }] }{ dt } \)

89.

KCl crystallises in the same type of lattice as does NaCl.Given that r_Na⁺/r_Cl^-=0.55 and r_K⁺/r_Cl^-=0.74.Calculate the side of the unit cell of KCl to that of NaCl

(a)

1.123

(b)

0.891

(c)

1.414

(d)

0.414

(e)

1.732

90.

Which of the following is true about the value of refractive index of Quartz glass?

(a)

Same in all directions

(b)

Different in different directions

(c)

Cannot be measured

(d)

Always zero

91.

Which of the following is not a characteristic of a crystalline solid?

(a)

Definite and characteristic heat of fusion.

(b)

Isotropic nature

(c)

A regular periodically repeated pattern of arrangement of constituent repeated pattern of arrangement of constituent particles in the entire crystal.

(d)

A true solid.

92.

The crystal with metal deficiency defect is

(a)

NaCl

(b)

FeO

(c)

KCl

(d)

ZnO

(e)

LiCl

93.

K_H value for Ar(g), CO₂(g), HCHO (g) and CH₄ (g) are 4.39,1.67,1.83 x 10^-5 and 0.413 respectively. Arrange these gases in the order of their increasing solubility.

(a)

\( \mathrm{HCHO}<\mathrm{CH}_4<\mathrm{CO}_2<\mathrm{Ar}\)

(b)

\( \mathrm{HCHO}<\mathrm{CO}_2<\mathrm{CH}_4<\mathrm{Ar} \)

(c)

\( \mathrm{Ar}<\mathrm{CO}_2<\mathrm{CH}_4<\mathrm{HCHO} \)

(d)

\( \mathrm{Ar}<\mathrm{CH}_4<\mathrm{CO}_2<\mathrm{HCHO} \)

94.

If sodium sulphate is considered to be completely dissociated into cations and anions in aqueous solution, the change in freezing point of water \((\Delta { T }_{ f })\), when 0.01 mol of sodium sulphate is dissolved in 1 kg of water, is (K_f = 1.86 K kg mol^-1).

(a)

0.0744K

(b)

0.0186K

(c)

0.0372K

(d)

0.0558K

95.

The molal freezing point constant of water is 1.86^o C/M. Therefore the freezing point of 0.1 M NaCl solution in water is expected to be

(a)

- 1.86^oC

(b)

- 0.186^oC

(c)

- 0.372^oC

(d)

+ 0.372^oC

96.

The property of crystalline solid is not

(a)

anisotropic

(b)

isotropic

(c)

hard

(d)

dense

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Answers Key:

Multiple Choice Question

96 x 1 = 96

(b)
Cetyltrimethylammonium bromide

(b)
chemotheraphy

(d)
bithional

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

10.

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

11.

(a)
three

12.

13.

(d)
terephthalic acid

14.

(b)
AlCl₃

15.

16.

(d)
1 and 4

17.

18.

19.

(b)
Glycine + \(\epsilon\)-aminocaproic acid

20.

(d)
Mn₂O₇

21.

(d)
Highly branched structure

22.

(d)
Glycogen

23.

(a)
Ti⁺,Ti³⁺

24.

25.

(a)
hydrazine in presence of feelby acidic solution

26.

(b)
C₆H₅OH; CH₃I

27.

(a)
o-nitrophenol shows intramolecular H-bonding

28.

(a)
Ranitidine

29.

(a)
phenol

30.

31.

(a)
Low density polythene

32.

(a)
five

33.

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

34.

35.

(b)
a mixture of benzene and Mg(OMe)Br

36.

(a)
Only II

37.

38.

(d)
bicarbonate

39.

40.

41.

(a)
\(\frac { 2 }{ 5 } \)

42.

(a)
HCl+ZnCl₂

43.

(d)
no isomerism

44.

(b)
m-Bromotoluene

45.

(d)
I₂/HNO₃

46.

(b)
trigonal bipyramidal

47.

(a) CH₃OC₂H₅ undergoes cleavage by S_N2 mechanism to give CH₃I and C₂H₅OH while (CH₃)₃COCH₃ undergoes cleavage by S_N1 mechanism to give (CH₃)₃CI and CH₃OH.

48.

(b)
isopropyl alcohol and methyl iodide

49.

(d)
All of these

50.

(b)
H₂O<H₂S<H₂Se<H₂Te : increasing pK_a values

51.

(a)
sodium

52.

(a)
2-Methylpropene

53.

(a)
2.5 V

54.

(b)
- 16.13

55.

(b)
2.24 mole

56.

(d)
1 x 10^-14

57.

(b)
Co³⁺, octahedral complex with strong field ligands

58.

(b)
Is used as a food preservatives

59.

(d)
Na₃AlF₆ and is used in the electrolysis of alumina for lowering the melting point and increasing the conductivity of alumina

60.

(a)
nitric oxide and nitrogen dioxide

61.

(a)
(NH₄)₂Cr₂O₇ and Cr₂O₃

62.

(a)
(i), (ii) and (iii)

63.

Conversion of carbonate into its oxide by heating in absence of air is called calcination.

64.

(d)
2-butene

65.

(b)
2HI + H₂SO4 \(\rightarrow\) I₂ + SO₂ + 2H₂O

66.

(b)
\(1.08\times { 10 }^{ -5 }\)

67.

(a)
less than \(\triangle H\)

68.

69.

(a)
N₂in both cases

70.

(a)
0.5 mol^-1dm³

71.

(d)
first

72.

(d)
10⁶

73.

(b)
2\(\times\) 0.693

74.

(b)
1.2\(\times 10 ^{-2 }\)

75.

(a)
CaCO₃\(\longrightarrow\)CaO+CO₂

76.

Physical adsorption decreases with increase of temperature. Hence, (d) is not favourable.

77.

(b)
Tyndall effect

78.

(d)
greater solubility of the impurity in the molten state than the solid

79.

80.

(a)
H₃PO₃is dibasic and reducing

81.

82.

83.

(a)
reverse reaction is involved

84.

(c)
The order of a reaction is always equal to the sum of the stoichiometric coeffecients of reactants in the balanced chemnical equation for reaction.

85.

(d)
1000

86.

(b)
k = \(\frac {2.303}{t} log \frac {p_i}{2p_i - p_i}\)

87.

(b)
0.01 M

88.

(d) \(\frac{1}{3} \frac { d[{ Br }_{ 2 }] }{ dt } =-\frac { 1 }{ 5 } \frac { d[{ Br }^{ - }] }{ dt } \) or \(\frac { d[{ Br }_{ 2 }] }{ dt } =-\frac {3 }{ 5 } \frac { d[{ Br }^{ - }] }{ dt } \)

89.

1.123

90.

Quartz glass is amosphous and hence refractive index is same in all directions.

91.

(b)
Isotropic nature

92.

(b)
FeO

93.

94.

(d)
0.0558K

95.

\(NaCl\longrightarrow { Na }^{ + }+{ Cl }^{ - },i=2\\ \Delta { T }_{ f }={ iK }_{ f }m=2\times 1.86\times 0.1={ 0.372 }^{ o }C,\\ { T }_{ f }={ 0.372 }^{ o }C.\)

96.