JWM CHEMICAL PAPER- 2011

8/12/2019 JWM CHEMICAL PAPER- 2011

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~. : .~ 1. Consider the following statements :

1 . the units of ionization potential areeV.

2. The second ionization potential ofMg is higher than second ionizationpotential of N a. '

3. The first ionization potential of Nais less than the first ionizationpotential of M g.

4. The first ionization potential of A I

is . less than the first ionizationpotential of Be.

Which of these statements are correct '?

(a) I, 2, 3 and 4

(b) J, 3 and 4

(c) 2 and 3 only

(d) 1 and 3 only

2. The electronegativity of elements X andY is 12 and 3 '() respectively. The bondfanned between X and Y would be

(a) Covalent

(b) Coordinate

(c) Metallic

C d ) Jonic

3 . Which one of the following compoundshas highest oxidation state of Mn ?

. 3) -Mn02 i'f. .j s5 KMn0

4.k:~ .

(e) Mnp4 X IX

(d) ~Mn04 1( \q

QS-LA-WJZP - A .

4, Mendeleev 's blank starts to fill fromwhich atomic numbers 7

. . .~(b) 57 and 89

(c) 56 and 88

(d) 55 and 87

5. Which , one of the following set of

quantum num~rs is possible 7

(a) 11=2 ,1=0 , m=Oands=-t

(b) 11=2 ,1 = 1 . m = Oand s = '-

(c) IP=2 .I=l ,m = Ol\nds=+ t

(d) n = 2, IE : -2, I I I = 2 and s 0

6. Thc fourth period of modem periodictable contains

(a) 18 transition elements

(b) 10 transition elements

(c) J8 non-transition elements

(d) 10 non-transition elements .

7. The electronic configuration of anelement having highest second ioniza-ti~alis ~

(a) 1.l2 'J.s2. 2p 6 and 3.v2

(b) 1$2. 'J.s2, 2p 6 3SZ and 3p2

(c) I?, 'J.s2, 2 p G 3 s 2 and 3 p 6

(d) I? i 2p6 and 3 .1'1

2


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8. The quantity of energy re leased when-1 0 6atoms of iodine in vapour stare areconverted to r ions is 5 x lO-t3 J . What

is the electron affinity (in KJ mol-I) ofiodine? (Take Avogadro's number as6 x 1023 )

(a) 30

(b) 3

(e) 3000

(d) s o o

9. Whin will be colour -of sugar if it isdehydrated ?

(a) 1 r8nspureIiI

(b) Grey

(c) Brown

(d) . Black

10. The number of two -centred-two 'e= bonds and three -centred-two e= oondspresent in diborane (B2~ are respec -tively

(a) Four and two

_ (b) Two and four

c Two and two

(d) Four and four

1 .On the basis of electronegativity values-of H. C. N, 0 and SasH 25 , 3 (). 3,5and 25 respectively, the most polar bandis

(a] C -H

(b) N-H

(cl S -H

(d) O -H

12. Concept of mixing of orbitals on anatom having nearly equal energy , 10produce entirely new orbitals which

have same energy contents , identicalshapes and are symmetrically disposedin space, is known as

(8) Hybridization

(b) Tetra covalency

(c) Resonance

(d) Hydrogen bonding

13. Whic~ one of the following statementsis correct ?

(8) The number of electrons present inthe valence shell of SF 6 is 12

(b) The dipole mo ment of water is zero

(c) The rates of ionic reaction s 8l'Cvery slow

(d) According to VSEPR . SnCl2 is 8linear molecule

14. In the ca lcium fluoride st ructure, thecoordination numb er ofthe cations andanions arc respec tivel y

(a) 6 and ~

(b) 8 and 4

(e) 4 and 4

(d) 4 and 8

15. Which fo rm of carbon exist as molecularform ?

(u) Graphite

(b) Diamond

(e) Carbon-blac k

(d) Fullerene

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16. Match List 1 with List II and select thecorrect answer using the code givenbelow the Lists:

List 1

A. Tetrahedral

B. Octahedral

C. Body-centredcubic

D. Planar triangle

Code:

A B

(a) 3 .

(b) 2

(c) 3 4

(d) 2 4

List 1I

I. 0414 to 0 732

2. 0225 to 0 -414

3. 0 155 to 0 225

4. 0732 to )-000

4 2

4 3

2

3

17. Match List I with List II and select thecorrect answer using th e code givenbelow th e Lists:

List I

A. Caesiumchloride

B.NaCI

C. CUzS

D.CadmiumIodide

Code:

LiS( II

I. Layer. structure

2. Non-stoichiometriccompound

3. Octahedral arrange -rnent

4. Body-centredcubic

A B C D

(a) 4 3 2

(b) 2 3 4(c) 4 2 3

(d) 3 2 .4

QS-LA-WJZP - A

8 The ionic radii of Rb' and 1 - arc: )47and 2-16A respectively. The mostprobable type of geometry exhibited byRbI on the basis of radius ratio rule is

(a) CsCI type

(b) NaC cype

(c) znS type

(d) Boron Oxide type. .

19. Which one of the following statementsis correct for non-conductivity indiamond ?

(a) Diamond is made up of non-metallic carbon

(b) Diamond has no molecular orbital

(c) Diamond has high refractive index

(d) Diamond has close packed arrange-ments of atoms .

20. Match List 1 with List JI and select thecorrect answer using the code givenbelow the Lists :

List List II

A. Solid 12 1. Insulator at oo}{

B.Ag 2. Good Conductor

C. UF 3. Insularor up to

D.Gemelting point

4. Insulator

Code:

A B C D

(a) 2 3 4

(b) 4 3 2(c) 3 2 4

(d) 4 2 3

4


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1. Which of the following compounds will

give carbylarnine on heating with

chloroform and alcoholic KOH ? -(3) Trimethylamine

(b) Diethylamine

(c) Ethylamine

(d) Dimethylaniline

22.. Consider the following carbocations :

1: CH 3 c H 2

2 CH z =c H

3 CH 2 = CH - C H z

4_ C6H~- C H}

The stability of these in decreasingorder is

(a) 1>2>3>4

(b) 4>3>2>-1

(c) 4>3>1>2

(d) 2> I- > 3> 4

23. Aldehydes other than 'formaldehyde,react with Grignard reagent to give -onadduct, which on acid hydrolysis give

(0) Secondary alcohols

(b) Carboxylic acids

(c) Primary ~lcohoJs

(d) - Aldehydes

24. A molecule is divided into two halveswhich are mirror images of each otherby

(a) A centre of inversion

(b) A plane of symmetry

c An axis of symmetry

(d) A centre of symmetry

25. One of tile following compounds -isu~C o r making plastic known as Bakelite

as well .as -for sterilization of surgicalinstruments and disinfectant in ourhouses

(a) Chloroform

(b) Carbon tetrachloride

(c) Alcohol

(d) Formaldehyde

26. Which of the following ingredients usedin the manufacture of synthetic deter-gents acts as Anti-redeposition agent?

(0) Sodium Silicate

(b) Sodium Sulphate

(c) Sodium Carboxyl methyl cellulose

(d) Sodium Tripolyphosphate

27. The most economical process to produceethylene commercially in - India iscrackmg of

(a) C,-e; fraction of natural gas

(b) Cz~3 fraction of naturaI gas

-(c) C 3 -C 4 frnction. of natural gas

(d) Naphtha

28. Among the technologies employed forCaustic soda production , the most c eo-friendly technology is

(0) Membrane cell

(b) Diaphragm cell

(e) Mercury cell

_(d) Chemical synthesis

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29. Ointments , Candles, Toiletr ies, Vaselineand Wax Pape : are obtained from thefollowing fraction of c racking of cru deail

(II) Paraffin WIlX

(b ) Heavy fuel oil

(c) Naphtha

(d) Diesel oil or gas oil

30. Liquefied Petroleum Gas (LPG) consists. of .

(a) Ethane and . Propane

(b) Propane and Butane

(e) Methane and Eihane

(d) Butane and Pentane

31. Kerosene havi ng smoke po int of 19 andsulphur content of 0 04% (by weight)will have aromatics content approxi-mately ~ual to

(a) 155 volume

(b) 76 volume %

(c) 475 vo lume (d) 47 5 volume

32. In pipe still heaters, used in Petroleumindustry, following two heating sectionsare ther e .

(a) Convection and Conduction

(b) Radi ation and Conduction

(c) Radiation and Convect ion

(d) Conduction and Boiling

33. Hydrogen is liberated when elect ro-chemical corros ion OCCw> in

(a) Acidic env ironment

(b) Busic envi ronment

(c) Neutral environment(d) Both a cidic and basic env ironment

}5 -LA-WJZP - J\

34.E

Heat flux vs. Temperature drop curve isshown above for bo iling water. Port ionAB is na tural convection .: what is BC?

35. I f the temperature of the liquid is lessthan the satura tion temperature . theprocess is called

(a) Sub cooled boil ing

(b) Pool boiling

(c): Bulk boiling

(d) None of the above

36. When crude o il is pumped throug h thefurnace. the first heat transfe r to thetubes occurs when the hot flue gases riseand heat the tubes. The oil tubes ' areheated first by the process of

(a) Conduction

(b) Convect ion

(c) Radiation

(d) Condensation

Healflux

A~ ~

Temperature drop

(a) Transition boiling

(b) Film boiling

(c) Nucleate bo iling

(d ) Forced convection

6


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37. Formation of tiny bubble in a liquid iscalled nucleation. A bubble nucleusformed in a bulk

otsuperheated liquid is

cnlled

(a) Homogeneous nucleation

(b) Heterogeneous nucleation

(c) Nucleate boiling

(d) None of these

38. Log mean temperature difference correc-tion factor is used for

(a) Single pass heat exchanger

(b) Multiple pass heat exchanger

(c) Double pipe heat exchanger

(d) Plate and frame heat exchanger

-

39. Consider the following stateme 'ts :

I. Thermal conducti vity gi yes measure .

of the effectivity of the material in. transmitting heat .

2. A material in crystalline state hashigher thermal conductivity than inamorphous state .

3. For meta ls, thermal conductivitydecreases with increase in tempera-ture (except Alu~inium)

4: Thermal conductivity decrease with

increasing amount of impurities inmetal.' .

Which of these statements are correct ?

(a) 1.2 and 3 only

(b) I, 3 and 4 only

(e) 1,2,3 and 4

(d) . 2, 3 and 4 only

40. Air at' 30C blows over a plate of50 em x75 em and maintained al 26


7/13

I ~ 44. Equation for turbulent flow mass

transfer 10 pipe walls is modificati on of

Sieder-Tate . equation (i.e. Nu = 0023ReO'8 Pr 3 ~.) with Nu an d-Pr numbersreplaced by

(a) Sherwood and Schmidt nos.

(b) Sherwood and Gmetz nos . .

(e) Schmidt and Graetz nos.


45. When unsteady stale diffusion takesplace in one direction in a solid orstagnant fluid, the governing differentialequation is called

(a) Fourier equation

(b) Knudsen equation

(c) Pick's second law of diffusion

(d) Nernst equation

46. The process of mass transfer from thebulk of one phase 10 the inter-phasesurface. and then from the inter-phase tothe bulk of another phase is termed as

(a) Homogeneous mass transfer

(b) Inter phase mass transfer

(c) Two phase mass transfer


47. In crystallization, the two phase mixtureof mother liquor and crystals of all sizes .which occupy the crystallizer and iswithdrnwn as product is called

(a) Mother liquor

(b) Crystals

(c) Yield

(d)' Magma

48. In which of the following case thenumber of overall gas phase transferunits will be equal to number of idealplates for the same degree of separa-lion?

~S-LA-WJZP - A

(a) The equilibrium line and operatinglines ar c nearly straight ,

(b) The equilibrium and operating linesare straight and parallel

(c) Slope of operating line is unity

(d) The equilibrium and operating linesare perpendicular to each other

49. 2 0 g of a radioactive isotope left 250 mgafter 24 hI'S. The half life period of theisotope is

(a ) 6 hr s

. (b) 24 hrs

(c) 8 hrs

(d) 4 hrs

SO. If water falls from the height of 100 mon the blades of a turbine at the r a r eof-to o kg/s, the power delivered to heturbine is

(a) 100 kW

(b) 10 kW(c) 1000 kW

(d) 1 kW

51. Pirani gauge used for pressure measure-ments has basic element

(a) Human hair

(b) Spiral bourdon

(c) Helical bourdon

(d) Filament of resistance wire

52. Typical specifications for control systemdesign are that the gain margin should begreater than 1 7. similar specificationsfor the phase margin must be

(a) Greater than 30

(b) Less than 30

(c) O

(d) Negative

Ii


8/13

53. Which one of the following thermo-couples develops least e.rn.f for the samedifference of temperature between hot

and cold junctions?(0) Ircn-consrantan

(b) Copper-constantan

(c) Chromcl-Alumel '

(d) Platinum-Platinum + 13% Rhodium

54. During the melting of a slab of ice at273 K at atmospheric pressure

l. Positive work is done by the ice-

water system on the atmosphere .. 2. Positive work is done on the ice-

water system by the atmosphere ..

. 3. The internal energy of the ice -watersystem increases .

4. The internal energy of the ice-watersystem decreases. .

(a) 1 . 2. 3 and 4 correct

(b) 2 and 3 only correct

(c) 2 and 4 only correct

(d) 3 and 4 only correct

55. C. and C p denotes the molar specificheat capacities of gas at constant volumeand constant pressure respectively, then

1. c ;, - C. is larger for a diatomicideal gas than for a monoatomicideal gas .

2. C p + Cv';s larger for a diatomicideal gas than for a monoatomicideal gas ..

3. Cpl C. is larger for a diatomic ideal..gas than for a monoatomic ideal

gas.

4. Cp C is larger-for a diatomic ideal 'gas than for a monoatomic idealgas.

(a) 1 and' 2 correct

(b) 2 and 4 correct

r 3 and 4 correct(d) 1 and 3 correct

56. A black body at absolute temperature Tis kept inside a closed chamber atabsolute temperature T O ' Sun rays areallowed to enter through an opening inthe chamber slightly and it is observedthat temperature T and T o remain same .Following statements can be made in

support of this observation?1. The Tate of emission of energy from

the black body remains the same .

2. The rate of emission of energy fromthe black body increases .

3. 1be rate of absorption of energy bythe black body increases .

4. The energy radiated by the blackbody equals the eneigy absorbedby.it .

Which of th~ statements are correct1

(a) and 4

(b) . I and 2

(~) 2 and 3

(d) 3 and 4

57. The Gibbs free energy and enthalpy. changes at 300K is-6694l1nd -'-4184kJ

respectively for a chemical reaction. Thechan~e in en~py .of the reaction inkJK' is

(a) 837

(b) 0 837

(e) 0 0837

Cd) 000837

9 A ... :QS -LA-WJZP


9/13

58. Potential energy of a mass of 15 kg is30 kJ. The approximate height of thebody t rooj the ground i~

(a) 10 m

(b) 20 m

(c ) 30 m

(d) 40 m

59. Cox chart used in the design of distilla-tion column is a plot of

(a) Temperature vs log (Vapour Pres -sure)

(b) Vapour Pressure vs log (Tempera-ture)

(c) Vapour P.rcssure vs Temperature

(d) Log (Temperature) vs log (VilpourPressure)

60. The degree of frceddm when a liquidsolution of methanol in water is inequilibrium with its vapour is

(a) 3(b) 2

(c) J

(d) 0

A h~t 'engine works between 137 C and3 1 C . The efficiency of the engine is

(a) 12 .

(b) 24%

. (c) 36

(d) 48%

62. The coefficient of Thermal expansion for ideal gas is given by

(a), T I

(b) p I

(c) TIP

(d) PlT

QS.LA.WJZP, - A

63. The relation between slope of vapour .pressure curve and molar heat ofvaporization is given by

(a) Clapeyron equation

(b) Fanning equation

(c) Chen's equation

(d) Ideal gas law

64. 12(.) + ~) ~ 2ffiW' AH = 124 kcal,The standard heat of formation of Hl is

(a) callmol

(b) 4 -2 kcaJ/mol

(e) 6 2 kcallmol

(d) 248 kcallmol

65. N p lug flow reactors in series with totalvolume V gives same conversion us

A single plug flow reactor ofvolume V

(b)' A single balch reactor of volume V

(c) A mixed flow reactor of volume V

(d) A single fluidized bed reactor ofvolum e V

66. A man (Volume = 0-015 m3 ) consumes12000 kJ of food per day. Assume foodis glucose and reaction is

C6HI206 + 60 2 ~ 6C0z + 6Hz0( - All) 3000 kJWhat is metabolic rate in terms of molesof 02 used per m 3 of person persecond 7

(0) 0{)()21

(b) 0- Q3 1

(e) 0-()047

(d) 0-0051


10/13

btc.-67. Milk is pasteurized jf it is heated ' to

336 K for- 30 minutes. However it takes

ooly 15 see when heated at 347 K . Theactivation energy forthis processwill be(a) 844 kllmol(b) 211 kl/mol

If 422 kl/mol .(d) 211 Hmol

68. Par the reaction.B+2D 43AThe relation b etw e en ra te -constants ks

ko and kA is given by .(a) k8 = t ko = t kA(b) kB = t ko = t kA(c) ks = 2 ko = 3 kA(d) ks =3 ko =2 k

69. If the Dispersion Number (DfIlL) is near .zero, th e flow p atte rn i ns id ethe reactoris

-=e)

(d)

Plug-flow'Mixed flowLaminar flowTurbulent flow

70. Consider th e following statements fo rdesign of nuclear reactors:

1.. For th e core of th e reactor oneneutron is produced after eachfission.

2. For steady chain react ion, themultiplication factor K . . should beequal to unity.

3. If neutron flux and heat output risesthe control rods should be reversed.

Which of these statements are correct ?(8) 1 and 3 only(b) I and 2 only(e ) 2 and 3 only(d) 1,2 and 3

71. In a Constant density system st arting--- with an initial concentration 0{ 01 mo l l

lit, th e' reaction rate is found to be0025 moillit, min. The reaction iscarried out in a CSTR fo r a space timeof 2 .min. The percentage conversionobtained is

(a) 50

(b) 80

(e) 2S

4 2

72. Which hydrocarbon from the followingshas least octane value 7

(a) Aromatics

. (b) Aliphatic

(c) Olctins'

(d) Cyclo-paraffins

73. Which one of the following is hav inghighest calorific value?

(8) Coal gas(b) O il gas

(c) Producer gas

(d) War .er gas

74. Light oil obtuined from high temperaturecarbonizat ion of coal is rich source of

(n) Benzene, Toluene and Xylene

(b) Benzene , Styrene and- Mesitylene

(c) Toluene , Styrene and Xylene(d) Toluene , Mesitylene and Cumene

75. The volume of air required for thecomplete combustion of 6 Its of CO . is(8) 71 Its

(b) 11 9 Its

(c) 1 4 3 Its

(d) 21 4 I ts

11 ~ - QS-LA-WJZP


11/13

76. The progressive transformation of woodto anthracite can be written as

(a) Wood ~ lignite ~ Peat ~ bitumi-nous ~ anthracite

~ Wood ~ peat ~ lignite ~ bitumi-,- nous ~ anthracite

(c) Wood ~ bituminous ~ peat ~lignite ~ anthracite

(d) Wood ~ bituminous ~ lignite ~

peat..... anthracite

77. Corrosion resistance of steel is increasedby the addition of

(a) P hO ip bO ru s a ndTungsten

(b) Nickel and Chromium

(e) Lead and Vanadium

(d) Molybdenum and Tungsten

78. An alloy of nickel and copper is used inFood and Chemical industry in evapo-rarors and heat exchangers. This alloyhas about 67 nickel and 30 copper.ihis is called

(a) Monel

(b) Inconcl

(c) Brass(d) Bronze

71}. Good thermal conductivity of refractingmaterial is desirable, if it is to be usedin the construction of walls of

(a) Blast furnace

(b) Reverberatory furnace .

(c) Muffle furnace(d) All of the above

QS-LAW\lZP - A

. 80. An increase in the carbide/gr~ite ratioin cast iron tends to

J. Increase the hardness

2. Increase the brittleness

3. Decrease the ductility

Which of these statements are correct?

J(a) 1 and, 3 only

(b) I and 2 only

(c) 2 and 3 only

(d) 1. 2 and 3

81. Which one of the following polymer iswidely used for making bullet proofmaterial?

(8) Polyethylene

PoJyamides(c) Polycarbonares

(d) Polyvinyl chloride

82. GR -S rubber is an example of

(a) Condensation polymerization

(b) Addition 'polymerization

(c) Copolymerization

(d) Cross-linked polymer

83. The polymer used for making contact -lens for eyes is

(a) Polyamide

~ Poly methyl mcth acryla te

(c) Polyalkene(d) Poly ethyl acrylate

12


12/13

.

84. A Polymer sample. contains equalnumber molecules of mol .wt 10,000 andmol. wt 100.000. What is the numberaverage molecular weight ( U N )of thepolymer sample?

(Ii) 5500(b) 550(e) 55 00(d) 55000

8S The intrinsic viscosity of a polymer is200 emJ g-I. What is the concentrationof the .polymer in water which would .

'have a relative viscosity of 15 ?(a) 25 x 10- 4 g cm-3

(b) 25 x 10-3 g em-3

. fc) 25 x 10-2 g em-3(d) 25 x 10-1 g erri-3

,', 86. The synthetic rubber used fo r makingconveyer belts; high 'a1til lde aircraftcomponents and , tank linings is

(a) Styrene rubber ffJ(b) Nitrile rubber 17(c) Neoperene rubber

J IfButyl rubber

87. In a polymer sample. all the asymmetriccarbon atoms have d -configuration . It isknown as(8) Isotacricpolymer(b) Atactic polymer

(e) Syndiotactic polymer

(d) Branched polymer

88. 'Butyl rubber is used for making innertubes for tyres . It is copolymer madefrom

(a) Butadiene' and styrene

j)f f Jsobutylene and Isoprene(e) Isoprene and styrene

(d) Butadiene and isoprene '

'89. 'How much rust (F~03' 3HzO) will beformed when 112 kg of iron havecompletely rust ed away? (Atomic wt of

Fe' 56. 0 = 16, H I)(a) 112 gtn

(b) 56 gm

(c) 214 gm

(d) 200 gm .

90. Rusting of iron is ,quicker in saline water. than in, ordinary water . It is because of

(a) Iron oxidation potential increases in ~c..'saline water

(b) Chloride has higher: reduction, potential

(e) Corrosion current increases insaline water.

(d) Iron undergoes concentration cellcorrosion in saline water

, .91, Water is flowing in a 25 mm id p ip eata velocity of 0 '()34 m s What'is thevalue of friction factor when viscosity of ~warer at 25C is 085 x 10-3 Ns/m2'7

(a) O ) 8 \. .

(b) O'()16 b / ~e (c) 0,16

(d) 0.(J()8

92. Cylindrical rings , used as packing inpacked towers and hav ing length equal10 diameter are known as

Y'Raschig rings

(b) Lessig rings

(c) P-,d l rings

(d) Berl saddles

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93. ~ nuclide has a half life of 40 days . If asample containing 800 atoms is allowedto decay for 12 0 days how many atomswill remain undecayed 1

(a) S O

(b) 100

(c) 200

Cd) 400

94. ~ rate of mass transfer is proportionalto

(a) Concentration driving foree

(b) Square of concentration drivingforce

(e) Product of mass and velocity

(d) Square roo t of mass flux

95. During nuclear fission reaction. whenuranium is bombarded by fast neutrons,which of the following reactions is nottaking place . in the nuclear reactors 1

(a) Uranium nucleus is split into twonearly equal -parts

(b) A considerable amount of energy isreleased

(c) The process is a self sustainingchain reaction , t for every . neutron used 2 to 3 neutrons aregenerated

(d) . Proto-actinium is produced in thereactor

H n t t I o n s

iach of the next Five (05) items consists ofwo statements, one labelled as the AssertionA)' and the other as 'Reason (R) . You are to'xamine these two statements carefully andelect the answers to these items using theodes given below :

~des :

(a) Both A and R are individually trueand R is the correct explanationof A

~LAWJZ}l - A

(b) BOIh A and R are individually truebut R is no t the correct explanationof A .

(c) A is true but R is false(d) A is false but R is true

96. Assertion (A) ; The ionization ene rgyof H and He are 1312KJmoJ-1 and 2378KJmol-1 respectively .

Reason (R) : This is due to increase innuclear charge of Hewhich is double of H.

,.,. Assertion (A) : In the liquid slate H2~is more highly assoc iatedvia 'hydrogen bondingthanHz

Reason (R) ; Z02 readily decomposeto zO according to theequation2Hz~ -+ 2Hz0 + ~

98. Assertion (A) : Carbon tetrachloride has. low boiling point (170C).

Reason (R) : The 'force of attractionbetween the moleculesof a covalent compoundis very weak .

99. Assert ion (A) : Oxygen is a gas butsulphur is a solid eventhough both belong tothe same group of tbeperiodic lable ,

Reason (R); Oxygen forms stablediatomic molecules butsul phur forms morecomplex molec ules.

100. Assertion (A) : Good conductors of hea tare also good conductorsof electricity and vice-versa.

R'CaSOn (R) : Electrons are responsiblefor these conductors.

4

JWM CHEMICAL PAPER- 2011

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