allen neet ug2013 chemistry paperwith solution

7/27/2019 Allen NEET UG2013 Chemistry Paperwith Solution

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1

CODE-Y

136. ThevalueofPlanck'sconstantis6.6310 34Js.

Thespeedoflightis310

17

nms

1

.Whichvalueisclosesttothewavelengthinnanometerofa

quantumoflightwithfrequencyof610 15s1?

( 1)75 (2)10

( 3)25 (4)50

Ans. (4)

Sol. =17 1

15 1

C 3 10 nms

6 10 s

=50nm

137. Theradical, CH2isaromaticbecauseit

has:-

( 1)6porbitalsand7unpairedelectrons




Ans. (2)

Sol.CH2

,Benzylfreeradicalisaromaticas

perHuckel'sruleithas6 electreonspresentin

p-orbitalofcarbonatomsinvolvedinformationof

benzenering(Aromaticnature).

CH2,6 electronsand6porbitals

138. Whichofthefollowingiselectron-deficient?( 1)PH3 ( 2)(CH3)2

( 3) ( SiH3)2 ( 4)( BH3)2

Ans. (4)

Sol.

B

HH

HH

B

H

H

3centre-2e bond

electrondeficient

( BH )3 2 B H2 6

NEET-UG 2013 TEST PAPER WITH SOLUTIONS

(HELD ON SUNDAY 05th MAY, 2013)

139. Whichof thefollowing statementsabout the

interstitialcompoundsis incorrect ?(1) Theyhavehighermeltingpointsthanthepure

metal

(2) Theyretainmetallicconductivity

(3) Theyarechemicallyreactive

(4) Theyaremuchharderthanthepuremetal

Ans. (3)

140. Howmanygramsofconcentrtedmitricacidsolution

shouldbeusedtoprepare250mLof2.0MHNO 3?

(1) 54.0conc.HNO 3

(2) 45.0conc.HNO 3

(3) 90.0conc.HNO 3

(4) 70.0conc.HNO 3

Ans. (2)

Sol. M=w solution

W 1000

M V ( mL)

2=W 1000

63 250

W=31.5g

70%HNO 3means70gHNO 3ispresentin100g

solution.

31.5gHNO 3willbepresentin100

7031.5

=45gofsolution

141. Which of the f ol l owing l anthanoid i ons i s

diamagnetic?

(Atoms,Ce=58,Sm=62,Yb=70)

(1) Yb2+ (2)Ce2+

(3) Sm2+ (4)Eu2+

Ans. (1)

Sol. dimagnetic now.e present

Yb+2=70[ Xe] 6s4f 14 5dU.e = zero.

142. Whichoneofthefollowingmoleculescontainsno

bond?

(1) NO2 (2) CO2

(3)H2O (4)SO 2

Ans. (3)


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NEET-UG-2013143. BasedonequationE=2.17810 18J

2

2

Z

n

certainconclusionsarewritten.Whichofthemis not

correct?

( 1)Forn=1,theelectronhasamorenegativeenergythanitdoesforn=6whichmeansthattheelectronismorelosselyboundinthesmallest

allowedorbit.(2)Thenegativesigninequationsimplymeansthat

theenergyofelectronboundtothenucleusis

lowerthanitwouldbeiftheelectronswereattheinfinitedistancefromthenucleus

(3)Largerthevalueofn,thelargeristheorbitradius

( 4)Equationcanbeusedtocalculatethechangeinenergywhentheelectronchangeorbit

Ans. (1)

Sol. Correctansweris-forn=1theelectronhasmorenegativeenergythanitdoesforn=6whichmeansthattheelectronislesslooselyboundinthesmallest

allowedorbit.

144. Inthereaction

NO2

N Cl2

Br

NO2

Br

AAis

(1)H+/H 2O (2) HgSO 4/H 2SO4( 3)Cu2Cl2 (4) H3PO 2andH 2O

Ans. (4)

Sol.

NO2

N Cl2

Br

H PO /H O3 2 2

NO2

Br

145. Theorderofstabilityofthefollowingtautomericcompoundsis:-

CH =CCH2 2CCH 3=

OH O

(I)

CH CCH CCH3 2 3==

O O

(II)

CH C=CH3 CCH 3=

OH O

(III)

( 1)II>III>I (2)I>II>III

( 3)III>II>I (4)II>I>IIIAns. (3)

Sol. Stabilityorderis

CH C=CHCCH3 3

OH O

CH CCH CCH3 2 3

O

>

O

CH =CCH CCH2 2 3

O

>

OH

Intramolecul arH-Bondingandconjugateddieneandithasinvolvedmore

acidicH[CH ]2

( Noconjugateddiene)

InvolvementoflessacidicHintautomerism

146. Nylonisanexampleof:-

(1) Polythene (2)Polyester

(3)Polysaccharide (4)Polymide

Ans. (4)

Sol. Nylonhaspolyamidelinkage.I t isformed by

condensationreactionofaminesandcarboxylicacid

groups.

147. XeF2isisostructuralwith:-

(1) BaCl 2 (2) TeF2 ( 3)ICl2 (4)SbCl 3

Ans. (3)

148. Thebasicstructuralunitofsilicatesis:-

(1)SiO42 (2) SiO ( 3)SiO4

4 (4)SiO32

Ans. (3)

Sol. Silicates Saltof silicicacid H 4SiO4

Si

OHHO OH

OH

4H +Si

O

O

O

O

,SiO 44

sil icateion

149. Whichof thefollowingstructureissimilarto

graphite?

(1)B2H6 (2) BN (3) B (4)B4C

Ans. (2)

150. Thestructureof isobutylgroupinanorganiccompoundis:-

(1)CH C3

CH3

CH3

(2) CHCH 2CH3

CH3

(4)CH CHCH CH3 2 3

(4)CH3CH2CH2CH2

Ans. (2)


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CODE-Y

Sol.

CH C3

CH3

CH3t-Butyl

CHCH 2CH 3

CH 3

isobutyl

sec-butyl

CH CHCH CH3 2 3 CH CH CH CH3 2 2 2

n-Butyl

151. Thenumberofcarbonatomsperunitcellofdiamond

unitcellis:-

( 1)1 ( 2)4 (3) 8 (4) 6

Ans. (3)

Sol. Inthediamondcubicunitcell,thereareeightcorner

atoms,sixfacecenteredatomsandfourmoreatoms

insidethestructure.

Numberofatomspresentinadiamondcubic

unitcell

=1+3+4=8atoms

152. AnexcessofAgNO 3isaddedto100mLofa0.01

Msol utionof dichlorotetraaquachromium( I I I )

chloride.ThenumberofmolesofAgClprecipitated

wouldbe:-

( 1)0.01 (2)0.001 (3)0.002 (4)0.003

Ans. (2)

153. Whatisthemaximumnumbersofelectronsthatcan

beassociatedwiththefollowingsetofquantum

numbers?

n=3, l=1and,=1

( 1)2 ( 2)10 ( 3)6 (4)4

Ans. (1)

Sol. n=3, =1andm=1representa3p-orbital

somaximum2electronscanbeaccomodateinit.

154. Whichof theseisnot amonomerforahigh

molecularmasssiliconepolymer?

( 1)PbSiCl 3 ( 2) MeSiCl3

( 3)Me2SiCl2 ( 4) Me3SiCl

Ans. (4)

Sol. Si l i cones are organo- si l i con pol ymer

containing ( SiOSi)

R

R

R

R

linkage.

SinceMe 3SiClcontainonlyoneCltherefore

it can't formhighmolecular masssilicon

polymer

I tact achainterminatingorganosilane

155. Areactionhavingequalenergiesofactivationfor

forwardandreversereactionshas:-

(1) H= G= S=0 (2) S=0

(4) G=0 ( 4) H=0

Ans. (4)

Sol. H=( Ea) f( Ea)b

Given:(Ea) f=(Ea) b

H=0

156. At25Cmolarconductanceof0.1molaraqueous

solutionofammoniumhydroxideis9.54ohm 1cm2

mol 1andatinfinitedilutionitsmolarconductance

is238ohm 1cm2mol 1.Thedegreeofionisation

ofammoniumhydroxideatthesameconcentration

andtemperatureis:-

(1) 40.800% (2) 2.080%

(3) 20.800% (4) 4.008%

Ans. (4)

Sol. %=

c

100=9.54

238100=4.008%

157. StructureofthecompoundwhoseIUPACnameis

3Ethyl2hydroxy4methylhex3en5ynoicacidis:-

(1) COOH

OH

(2)COOH

OH

(3)

COOH

OH

(4)

COOH

OH

Ans. (3)

Sol.

32

COOH1

4

5

6

OH

3-Ethyl-2-hydroxy-4-methylhex-3-ex-5-ynonicacid


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NEET-UG-2013158. Amongthefollowingethers,whichonewillproduce

methylalcoholontreatementwithhotconcentrated

HI?

( 1)CH CHCH OCH3 2 3

CH3

(2)CH3CH2CH2CH2OCH 3

( 3)CH CH CHOCH3 2 3

CH3

( 4)CH COCH3 3

CH3

CH3

Ans. (4)Sol. CObondcleavageofetherdependsonmechanism

involvedinreactionwhichcanbeSN 1orSN 2.Ifany

onegroupcanformstablecarbocationliketertiary

butylgroupthenreactionfollow'sSN 1mechanism

CH COCH3 3HI

Hot&conc.

CH3

CH3

CH COCH3 3

CH3

CH3

CH CI3

CH3

CH3

ICH C3

CH3

CH3

+ CH OH3

H

Methylalcohol

159. Antisepticsanddisinfectantseitherkillorprevent

growthof microganisms.Identify whichofthe

followingstatementsis nottrue :-

( 1)Disinfectantsharmthelivingtissues

( 2)A0.2%solutionofphenolisanantisepticwhile

1%solutionactsasadisinfectant

( 3) Chl orineand I odine are used as strong

disinfectants

( 4)Dilutesolutionsof BoricacidandHydrogen

Peroxidearestrongantiseptics

Ans. (4)

160. Amagneticmomentof1.73BMwillbeshownby

oneamongthefollowing:-

( 1)[CoCl6]4 (2)[Cu( NH3)4]

2+

( 3)[ Ni(CN)4]2 (4) TiCl4

Ans. (2)

Sol. Magneticmoment1.73BM

n n 2 B.M

n=no.of unpairede

=1.731.73= n n 2 B.M

n=1

* [ CoCl6]4 Co +2 ;d 7

Cl( weakfieldligand) t 2g5eg2unpairede =3

* [ Cu( NH3)4]2+ Cu +2 d 9

NH3Strongfieldligand,hybridisationdsp 2

* onee of 3djumpsinto4psubshell.

unpairede = 1

* [ Ni( CN)4]2 Ni +2d 8unpairede =0CN Strongfieldligand dsp 2

* TiCl4 Ti +4dunpairede =zero.161. KMnO4canbepreparedfromK 2MnO4asperthe

reaction:-

3MnO 42+2H 2O 2MnO 4

+MnO 2+4OH

ThereactioncangotocompitionbyremovingOH

ionsbyaddings:-

(1)SO2 ( 2)HCl

(3) KOH (4)CO 2

Ans. (4)

162. Reactionby which Benzal dehydecannot be

prepared:-

(1) +Zn/Hgandconc.HCl

(2) +CrO 2Cl2inCS 2followedbyH 3O

(3) +H 2inpresenceofPd+BaSO 4

(4) +CO+HClinpresenceofanhydrous

AlCl3

Ans. (1)


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CODE-YSol. InpresenceofZnHgandconc.HClreductionis

useful speciall y for al dehydeand ketonebut

carboxylicgroupremainsuneffected

CH3

CrO Cl +CS /H O2 2 2 3

CHO

Etardreaction

H /Pd+BaSO2 4

RosenmundReaction

COCl CHO

Co+HCl/AlCl 3

GattermanKochReaction

CHO

163. Whichofthefollowingdoesnotgiveoxygenon

heating?

(1) (NH4)2Cr2O7 ( 2)KClO3(3) Zn(ClO3)2 ( 4)K2Cr2O7

Ans. (1)

Sol. ( NH4)2Cr 2O7 N 2+Cr 2O3+4H 2O

donotproducesO 2.

164. Ametalhasafcclattice.Theedgelengthofthe

unitcellis404pm.Thedensityofthemetalis2.72g

cm3.Themolarmassofthemetalis :-

( 1)20gmol 1 ( 2) 40gmol 1

(3) 30gmol 1 ( 4) 28gmol -1

Ans. (4)

Sol. =

3A

Z M

N aforFCC,Z=4

a=404pm=40410 10cm.

2.72=

23 10 3

4 M

6.02 10 ( 404 10 )

M=27gmol 1

165. Dipoleinduceddipoloeinteractionsarepresentin

whichofthefollowingpairs:-

( 1)SiF4andHeatoms ( 2)H 2Oandalcohol

( 3)Cl2andCCl 4 ( 4) HClandHeatoms

Ans. (4)

Sol. Dipole-induceddipoleoccursbetweenpolar

&Non-polarmolecule

HCl He

Polar Non-polar

0 =0

166. Roastingof sulphidesgivesthegasX asaby

product.Thisiscolourlessgaswithchokingsmelof

burnt sul phur and causes great damage to

respiratoryorgansasaresultofacidrain.Itaqueous

solutionisacidic,actsasreducingagentanditsacidhasneverbeenisolated.ThegasXis:-

(1) SO3 ( 2) H2S (3) SO2 (4)CO2

Ans. (3)

167. Somemeta-directing substituentsin aromatic

substitution are gi ven. Whi ch one is most

deactivating?

(1) NO2 (2)CN

(3) SO3H (4)COOH

Ans. (1)

Sol. Deactivatingpower:

NO 2>C N>SO 3H>COOH

168. Nitrobenzeneonreactionwithconc.HNO 3/H 2SO4at80-100Cformswhichoneof thefollowing

products?

(1) 1,2,4-Trinitrobenzene

(2) 1,2-Dinitrobenzene



Ans. (3)Sol.

NO2

conc.HNO +conc.H SO3 2 4

80100 C0

NO2

NO21,3-Dinitrobenzene

Mixture of [ Conc HNO 3 conc H 2SO 4] gives

2NO

whichactsaselectrophileandinnitrobenzene

NO2groupismdirectinggroupso 2NO

attacks

atmposition.

169. Ahydrogengaselectrodeis madeby dipping

platinumwireinasolutionofHClofpH=10and

bypassinghydrogengasaroundtheplatinumwire

atoneatmpressure.Theoxidationpotentialof

electrodewouldbe?

(1) 1.81V (2) 0.059V

(3) 0.59V (4) 0.118V

Ans. (3)


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NEET-UG-2013Sol.

1

2H2(g) H

++e

EO.P. =EO.P.

0.059

n log

1/2H2

[ H ]

( P )

EO.P. =00.059

1log

10

1/2

10

(1)

( pH=10,[ H +]=10 10M)

EO.P. =0.59V

170. Whichofthefollowingisapolarmolecule?

( 1)XeF4 ( 2)BF3 (3) SF4 ( 4)SiF4

Ans. (3)

Sol. Unsymmetricaldistributionofe cloudleads

totheformationofpolarmolecule

H

H

Xe

H

H

B

FF=0

F

S

F

0

F

F

FSi

FF

=0

F

F

171. Abuttoncellusedinwatchesfunctionasfollowing

Zn( s) +Ag2O( s) +H 2O()2Ag( s)+

Zn2+( aq)+2OH (aq)

Ifhalfcellpotentialsare

Zn2+( aq)+2e Zn(s);E=0.76V

Ag2O(s) +H 2O() +2e2Ag( s)+2OH (aq);

E=0.34V

Thecellpotentialwillbe:-

( 1)1.34V (2)1.10V ( 3)0.42V (4)0.84V

Ans. (2)

Sol. Zn2+( aq)+2e Zn( s) ;E=0.76V

Ag2O(s) +H 2O() +2e2Ag(s)+2OH ( aq);

E=0.34V

Zn( s) +Ag2O( s) +H 2O() 2Ag(s) +Zn+2( aq)

+2OH ( aq);Ecell=?

Ecell=(ER.P. )cathode ( ER.P. )anode

Ecell=0.34( 0.76)=1.10VEcell=Ecell=1.10V

172. Whichoftheseis leastlikely toactasaLewisbase?

(1) PF3 (2) CO (3)F (4)BF3

Ans. (4)

173. Whichofthefollowingcompoundswillnotundergo

Friedal-Craft'sreactioneasily:-

(1) Toluene (2) Cumene

(3)Xylene ( 4) Nitrobenzene

Ans. (4)

Sol. FriedalCraftreactionfailswhenstrongdeactivating

groupisattachedwithbenzenering.

174. Which is the monomer of Neoprenein the

following ?

(1) CH2=CHCCH (2)CH 2=CHCH=CH 2

(3) ( 4)

Ans. (4)

Sol.

nCH =CCH=CH2 2

Cl

Polymersation

Chloroprene

CH C=CHCH 2 2

Cl nNeoprene

[Artificialrubber]

175. 6.0210 20moleculesofureaarepresentin100mL

ofitssolution.Theconcentrationofsolutionis:-

(1) 0.1M (2)0.02M

(3) 0.01M (4) 0.001MAns. (3)

Sol. Numberofmoles=A

number of molecules

N

=

20

23

6.02 10

6.02 10=10 3mol

Molarconc.=

solution

n 1000

V ( mL)=

310 1000100

Molarconc.=0.01M


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CODE-Y176. Maximumdeviationfromideal gasisexpected

from :

(1) NH3(g) (2) H2(g) ( 3)N2( g) (4) CH4(g)

Ans. (1)

Sol. NH3willshowmaximumdeviationfromidealgas

duetodipole-dipoleattraction.

177. Whichofthefollowingisparamagnetic?

( 1)NO+ (2)CO ( 3)O2 ( 4)CN

Ans. (3)

Sol. O215e containsoneunpairede in

ABMO.

1s 2* 1s22s 2* 2s2 2z2p 2x2p = 2y2p *

178. Identifythecorrectorderofsolubilityinaqueous

medium:

( 1)Na2S>ZnS>CuS

( 2)CuS>ZnS>Na 2S

( 3)ZnS>Na 2S>CuS

( 4)Na2SZnS

Ans. (1)

179. Whatistheactivationenergyforareactionititsrate

doubleswhenthetemperatureisraisedfrom20C

to35C?(R=8.314Jmol 1K1)

( 1) 15.1kJmol 1 (2)342kJmol 1

(3) 269kJmol 1 (4)34.7kJmol 1

Ans. (4)

Sol. log

2

1 1 2

K Ea 1 1

K 2.303R T T

2 21 1

r K2

r K

log2=

3Ea 1 1

293 3082.303 8.314 10

Ea=34.7KJmol 1

180. Whichisthestrongestacidinthefollowing?

(1)H2SO3 ( 2)H2SO4 (3)HClO3 (4)HClO4

Ans. (4)

allen neet ug2013 chemistry paperwith solution

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