No. of pages - 24 PRACTICE PAPER (2021-22) CLASS : XII

XII-CHEMISTRY-E 1

No. of pages - 24 PRACTICE PAPER (2021-22)

CLASS : XII SUBJECT: CHEMISTRY THEORY (043)

Time Allowed : 90 Min. Maximum Marks : 35 le; % 90 feuV vf/dre vad & 35 lkekU; funsZ'k&

1- iz'u i=k esa rhu [kaM gSaA

2- [k.M d esa 25 iz'u gSaA dksbZ 20 iz'u gy djsaA

3- [k.M [k esa 24 iz'u gSaA dksbZ 20 iz'u gy djsaA

4- [k.M x esa 6 iz'u gSaA dksbZ 5 iz'u gy djsaA

5- lHkh iz'uksa ds vad leku gSaA

6- dksbZ udkjkRed vadu ugha gSA

General Instructions: 1. The question paper contains three sections. 2. Section-A has 25 questions. Attempt any 20 questions. 3. Section-B has 24 questions. Attempt any 20 questions. 4. Section-C has 6 questions. Attempt any 5 questions. 5. All questions carry equal marks. 6. There is no negative marking.

************** [k.M&d (SECTION-A)

bl [k.M esa 25 cgqfodYih; iz'u gSa ftuesa ls dksbZ Hkh 20 iz'uksa osQ mÙkj nhft,A

20 ls vf/d iz'uksa osQ mÙkj nsus ij igys gy fd, x, 20 iz'u ewY;kadu osQ gsrq

ekU; gksaxsA

This section consists of 25 multiple choice questions with overall choice to attempt any 20 questions. In case more than desirable number of questions are attempted, ONLY first 20 will be considered for evaluation.

XII-CHEMISTRY-E 2

1. dkSu lk ;kSfxd viuh fozQLVyh; voLFkk esa 'kkWVdh ,oa izsaQdsy nks"k fn[kkrk gS &

(a) AgBr (b) ZnS (c) KBr (d) CsCl Which compound is likely to show both Schottky and Frenkel defects in its

crystalline form? (a) AgBr (b) ZnS (c) KBr (d) CsCl

2. flyhdksu dkckZbM mnkgj.k gS &

(a) lgla;kstd Bksl (b) /kfRod Bksl

(c) vk;fud Bksl (d) vk.kfod Bksl

Silicon carbide is an example of : (a) Covalent solid (b) Metallic solid (c) Ionic solid (d) Molecular solid

3. fuEu esa ls dkSu lk foy;u tksM+k leku rkieku ij vkblksVksfud foy;u gS\

(a) 0.1M ;wfj;k ,oa 0.1M NaCl

(b) 0.1M NaCl ,oa 0.1M Na2SO4

(c) 0.1M ;wfj;k ,oa 0.2M MgCl2

(d) 0.1M Na2SO4 ,oa 0.1M Ca(NO3)2

Which pair of solutions is isotonic at same temperature? (a) 0.1M urea and 0.1M NaCl (b) 0.1M NaCl and 0.1M Na2SO4

(c) 0.1M urea and 0.2M MgCl2

(d) 0.1M Na2SO4 and 0.1M Ca(NO3)2 4. mQ¡ps ioZrh; {ks=kksa esa vkDlhtu dh lkUnzrk ekuo ds jDr ,oa mQÙkd esa de gksus

dk dkj.k gS &

(a) fuEu ok;qe.Myh; nkc (b) fuEu rkieku

(c) vf/dre ok;qe.Myh; nkc (d) nksuksa nkc o rki mPp

XII-CHEMISTRY-E 3

Low concentration of oxygen in blood and tissues in the human at high altitude is due to :

(a) Low atmospheric pressure

(b) Low temperature

(c) High atmospheric pressure

(d) Both temperature & high atmospheric pressure

5. Xywdksl ds fy, lgh dFku dks igpkfu, &

(a) Ý;wjsuksl voLFkk esa mifLFkr gSA

(b) ;g ,d ,YMksgsDlkst gSA

(c) ;g 2, 4-DNP VsLV ugha nsrkA

(d) ;g HI ds lkFk xeZ djus ij n-gsDlsu nsrk gSA

Find correct statement from the following for glucose:

(a) It is present in furanose form

(b) It is an aldohexose

(c) It does not give 2, 4-DNP test

(d) It forms n-hexane when heated with HI

6. ,FkkukWy dks ,Fksuy esa ifjofrZr djus esa fdl vfHkdeZd dk iz;ksx gksrk gS&

(a) H2/Ni (b) KMnO4

(c) LiAlH4 (d) PCC

Reagent used for the conversion of ethanol to ethanal is :

(a) H2/Ni (b) KMnO4

(c) LiAlH4 (d) PCC

XII-CHEMISTRY-E 4

7. ,lhVhys'ku djkus ij Xyqdkst nsrk gS &

(a) VªkbZ,lhVsV (b) VsVjk,lhVsV

(c) isUVk,lhVsV (d) gSDlk,lhVsV

On acetylation reaction glucose gives :

(a) Triacetate (b) Tetra-acetate

(c) Penta-acetate (d) Hexa-acetate

8. vfHkfozQ;k esa ‘A’ vkSj ‘B’ dh igpku dhft, &

2Dry H O3 etherCH Cl Mg A B

(a) A=CH4, B=CH3MgCl (b) A=CH3MgCl, B=CH3–OH

(c) A=CH3MgCl, B=CH4 (d) mijksDr esa ls dksbZ ugha

Identify A and B in the reaction:

2Dry H O3 etherCH Cl Mg A B

(a) A=CH4, B=CH3MgCl (b) A=CH3MgCl, B=CH3–OH

(c) A=CH3MgCl, B=CH4 (d) None of the above

9. oxZ&16 ds gkbMªkbM ds DoFkukad dk mfpr ozQe gS &

(a) H2O > H2Te > H2Se > H2S (b) H2O > H2S > H2Se > H2Te

(c) H2Te > H2O > H2Se > H2S (d) H2Te > H2Se > H2S > H2O

Correct order of boiling points of hydrides of group 16 is :

(a) H2O > H2Te > H2Se > H2S (b) H2O > H2S > H2Se > H2Te

(c) H2Te > H2O > H2Se > H2S (d) H2Te > H2Se > H2S > H2O

XII-CHEMISTRY-E 5

10. mRo`Q"V xSl Lih'kht ds lw=k tks Øe'k% 4ICl rFkk 2IBr ds le jpukRed gS %

(a) XeF4, XeF2 (b) XeF2, XeF4

(c) XeF4, XeF+ (d) XeF2, XeO3

The formula of the noble gas species which are isostructural with 4ICl and

2IBr are respectively :

(a) XeF4, XeF2 (b) XeF2, XeF4

(c) XeF4, XeF+ (d) XeF2, XeO3

11. ?kuh; lqlaoqQfyr lajpuk esa fdrus prq"iQydh; 'kwU; gksaxs &

(a) 10 (b) 4

(c) 6 (d) 8

Number of tetrahedral voids in CCP structure are :

(a) 10 (b) 4

(c) 6 (d) 8

12. f=kurk{k ,dd lsy ds fy, v{kh; nwjh vkSj v{kh; dks.k gS &

(a) a b c, 90 (b) a b c, 90

(c) a b c, 90 (d) a b c, 90

Axial distances and axial angles for triclinic unit cell are:

(a) a b c, 90 (b) a b c, 90

(c) a b c, 90 (d) a b c, 90

13- ;fn NaCl dks SrCl2 ds 10–3 eksy » ls vifefJr fd;k tk,] rks /uk;ukas dk

lkanz.k gksxk &

(a) 6.022 × 1018 (b) 60.22 × 1018

(c) 6.022 × 1020 (d) 6.022 × 1021

XII-CHEMISTRY-E 6

If NaCl is doped with 10–3 mol % of SrCl2, the concentration of cation vacancies are :

(a) 6.022 × 1018 (b) 60.22 × 1018

(c) 6.022 × 1020 (d) 6.022 × 1021

14. fuEu esa ls fiQukWy fdl ls de vEyh; gksrk gS\

(a) O-feFkkbyiQhukWy (b) O-feFkksDlhiQhukWy

(c) O-ukbVªksiQhukWy (d) ,FkukWy

Phenol is less acidic than which of the following :

(a) O-Methylphenol (b) O-Methoxyphenol

(c) O-Nitrophenol (d) Ethanol

15. dkcksZgkbMªsV~l dk lkekU; lw=k gS &

(a) CnH2nO (b) CnH2n+1O

(c) Cn(H2O)2n (d) Cx(H2O)y

General formula for carbohydrates is :

(a) CnH2nO (b) CnH2n+1O

(c) Cn(H2O)2n (d) Cx(H2O)y

16. dkSu lk ,Ydkby gSykbM tks vklkuh ls SN1 iznf'kZr djrk gS &

(a) (CH3)3 C–Cl (b) (CH3)3–C–Br

(c) (CH3)3 C–F (d) (CH3)3 C–I

Alkyl halides which will undergo 1NS reaction most readily is :

(a) (CH3)3 C–Cl (b) (CH3)3–C–Br

(c) (CH3)3 C–F (d) (CH3)3 C–I

XII-CHEMISTRY-E 7

17. nks rRo ‘P’ ,oa ‘Q’ ls ,d ?kuh; Bksl cuk gSA ?ku ds dksuksa ij ‘Q’ ijek.kq ,oa

dk; dsUnz ij ‘P’ ijek.kq fLFkr gSaA ml ;kSfxd dk lw=k gksxk &

(a) PQ (b) P2Q

(c) PQ3 (d) PQ2

A cubic solid is made up of two elements ‘P’ and ‘Q’. Atoms of ‘Q’ are at the corners of the cube and ‘P’ at the body centre. Formula of the compound is :

(a) PQ (b) P2Q

(c) PQ3 (d) PQ2

18. iQyd dsafnzr ?ku ,dd lsy esa ijek.kqvksa dh la[;k gksxh&

(a) 4 (b) 1

(c) 3 (d) 2

Total number of atoms per unit cell of FCC crystal are :

(a) 4 (b) 1

(c) 3 (d) 2

19. ml foy;u dk ijklj.k nkc D;k gksxk ftlds 0.3 mol/L foyk;d T rkieku ij

gS %

(a) 0.3RT (b) 0.03RT

(c) 0.003RT (d) 3RT

The osmotic pressure of a solution containing 0.3 mol of solute per litre at T temperature is:

(a) 0.3RT (b) 0.03RT

(c) 0.003RT (d) 3RT

XII-CHEMISTRY-E 8

20. NaOH ds 4g dks 500 fe-yh- ikuh esa ?kksyus ls cuus okys foy;u dh eksyjrk

gS&

(a) 0.4 M (b) 0.8 M (c) 0.2 M (d) 0.1 M The molarity of NaOH solution formed by dissolving 4g of it in 500 ml of

water is : (a) 0.4 M (b) 0.8 M (c) 0.2 M (d) 0.1 M

21. tc CH3–Cl o AgF vfHkfozQ;k djrs gSa rks eq[; mRikn curk gS &

(a) CH3–F (b) CH3–Ag (c) CH3AgCl (d) CH4

The main product obtained after reaction of CH3–Cl and AgF is : (a) CH3–F (b) CH3–Ag (c) CH3AgCl (d) CH4

22. fuEufyf[kr vfHkfØ;k esa ‘X’ rFkk ‘Y’ dh igpku dhft, &

Identify ‘X’ and ‘Y’ in the following reaction:

XII-CHEMISTRY-E 9

23. izksVhu esa ikWyhisIVkbM J`a[kykvksa esa ,ehuks vEyksa ds ozQe dks dgrs gSa &

(a) r`rh;d lajpuk (b) izkFkfed lajpuk

(c) f}rh;d lajpuk (d) mijksDr esa ls dksbZ ugha

The sequence of -amino acids in a polypeptide chain in a protein is called its:

(a) Tertiary structure (b) Primary structure

(c) Secondary structure (d) None of these

24- fuEu gkbMªkbM esa ls dkSu lcls de {kkjh; gS &

(a) NH3 (b) PH3

(c) AsH3 (d) SbH3

The least basic hydride among the following is :

(a) NH3 (b) PH3

(c) AsH3 (d) SbH3

25. SO2 dk;Z ugha djrh &

(a) vkDlhdj.k vfHkdeZd (b) futZyhdj.k vfHkdeZd

(c) vipk;d vfHkdeZd (d) Cyhfpax vfHkdeZd

SO2 does not act as:

(a) Oxidising agent (b) Dehydrating agent

(c) Reducing agent (d) Bleaching agent

XII-CHEMISTRY-E 10

SECTION-B

[kaM&c (SECTION-B)

bl [kaM esa fdlh Hkh 20 iz'uksa dks gy djus ds fy, lexz fodYi ds lkFk 24

cgqfodYih; iz'u gSaA ;fn okafNr la[;k ls vf/d iz'uksa dk iz;kl fd;k tkrk gS

rks ewY;kadu ds fy, dsoy igys 20 ij fopkj fd;k tk,xkA

This section consists of 24 multiple choice questions with overall choice to attempt ANY 20 questions. In case more than desirable number of questions are attempted ONLY first 20 will be considered for evaluation.

26. ,d iz;ksxkRed ijh{k.k esa /kfRod vkWDlkbM dk lw=k M0.98O gS /krq M ;gk¡ ij

M2+ vkSj M3+ ds :i esa gS tks buds vkWDlkbM esa gSA /krq tks M3+ ds :i eas gS

mldh » gS %

(a) 5.08% (b) 6.05%

(c) 4.08% (d) 7.01%

Experimentally it was found that a metal oxide has formula M0.98O. Metal M is present as M2+ and M3+ in its oxide. Fraction of the metal which exists as M3+ would be found in percentage.

(a) 5.08% (b) 6.05%

(c) 4.08% (d) 7.01%

27. ,d iQyd dsafnzr ?ku fØLVy tks 100 xzke ek=kk esa gS bldh v{kh; nwjh 200 pm o ?kuRo d=10 g cm–3 esa ijek.kq la[;k gksxh &

(a) 3 × 1023 (b) 2 × 1025

(c) 5 × 1024 (d) 1 × 1025

The number of atoms in 100 g of a FCC crystal structure with density d = 10 g cm–3 and cell edge as 200 pm is equal to :

(a) 3 × 1023 (b) 2 × 1025

(c) 5 × 1024 (d) 1 × 1025

XII-CHEMISTRY-E 11

28. fdruh ,dd lsy mifLFkr gS ;fn NaCl fozQLVy ?ku ds :i esa gS ftldk

nzO;eku 1.00 g gSA

(a) 2.57 × 1021 (b) 5.14 × 1021

(c) 1.71 × 1021 (d) 1.28 × 1021

How many unit cells are present in a cube shaped ideal crystal of NaCl of mass 1.00 g:

(a) 2.57 × 1021 (b) 5.14 × 1021

(c) 1.71 × 1021 (d) 1.28 × 1021

29. 2.5g ,slhfVd vEy (CH3COOH) dh eksyyrk 75g csathu esa gksxh&

(a) 5.55 mol kg–1 (b) 55.6 mol kg–1

(c) 556.0 mol kg–1 (d) 0.556 mol kg–1

The molality of 2.5g of ethanoic acid (CH3COOH) in 75g benzene is :

(a) 5.55 mol kg–1 (b) 55.6 mol kg–1

(c) 556.0 mol kg–1 (d) 0.556 mol kg–1

30. ,d Non bySDVªksykbV foys; dh ek=kk 1.00g dks 51.2 g, C6H6 esa ?kksyk x;kA

blds fy, fgekad voueu fLFkjkad 5.12 K kgmo–1 gSA C6H6 ds fgekad dk

voueu gksxk & (foys; dk nzO;eku = 250g mol–1)

(a) 0.4 K (b) 0.5 K

(c) 0.3 K (d) 0.2 K

A non-electrolyte solute quantity 1.00g was dissolved in 51.2 g of C6H6. If freezing point depression constant, kg of C6H6 is 5.12 K kgmol–. The freezing point of C6H6 will be lowered by – (Given molar mass of solute = 250 g mol–1)

(a) 0.4 K (b) 0.5 K

(c) 0.3 K (d) 0.2 K

XII-CHEMISTRY-E 12

31. xUus dh phuh dk 5» ?kksy (eksy nzO;eku ¾ 342) ,d inkFkZ X ds 1» ?kksy ds

lkFk leijklh gS] X dk eksyj nzO;eku gS &

(a) 171.2 g mol–1 (b) 68.4 g mol–1

(c) 34.2 g mol–1 (d) 136.2 g mol–1

A 5% solution of cane sugar (molar mass = 342) is isotonic with 1% solution of a substance X. The molar mass of X is :

(a) 171.2 g mol–1 (b) 68.4 g mol–1

(c) 34.2 g mol–1 (d) 136.2 g mol–1

32. tc AgCl, NH3 ls vfHkfØ;k djrk gS] rks D;k ifjorZu ns[kk tkrk gS\

(a) lisQn vo{ksi curk gS (b) jaxghu lek/ku curk gS

(c) ihyk vo{ksi curk gS (d) dksbZ ifjorZu ugha ns[kk x;k gS

What is the change observed when AgCl reacts with NH3?

(a) White ppt is formed (b) Colourless solution is formed

(c) Yellow ppt is formed (d) No change is observed

33. ClO– fdl mnklhu v.kq ds lkFk le&bysDVªkWfud gS\

(a) ClF3 (b) ClF

(c) BrCl (d) BrF

With what neutral molecule is ClO– isoelectronic?

(a) ClF3 (b) ClF

(c) BrCl (d) BrF

XII-CHEMISTRY-E 13

34. fuEu esa ls dkSu lk lgh vEyh;k ozQe gS &

(a) HClO2 < HClO < HClO3 < HClO4

(b) HClO4 < HClO2 < HClO3 < HClO

(c) HCl4 < HClO3 < HClO2 < HClO

(d) HClO < HClO2 < HClO3 < HClO4

Out of the following which one is the correct order of acidic strength :

(a) HClO2 < HClO < HClO3 < HClO4

(b) HClO4 < HClO2 < HClO3 < HClO

(c) HCl4 < HClO3 < HClO2 < HClO

(d) HClO < HClO2 < HClO3 < HClO4

35. tc Dyksjhu xeZ ,oa lkanz tyh; NaOH ds lkFk vfHkfØ;k djrh gS] rks izkIr gksus

okys mRikn gksaxs &

(a) Cl– rFkk 3ClO (b) Cl– rFkk 2ClO

(c) ClO– rFkk 3ClO (d) 2ClO rFkk 3ClO

The products obtained when chlorine gas reacts with hot and concentrated aqueous NaOH are :

(a) Cl– and 3ClO (b) Cl– and 2ClO

(c) ClO– and 3ClO (d) 2ClO and 3ClO

36. fuEu :ikUrj.k ds fy, vfHkdeZdksa dk lgh ozQe gksxk&

3 3

2 5

CH CHO CH CH OH|C H

(a) CH3MgCl, H2O/H+ (b) CH3CH2MgCl, H3O+

(c) (CH3)3 C–MgBr, H2O/H+ (d) CH3–CH2–CH2MgCl, H2O/H+

XII-CHEMISTRY-E 14

The correct sequence of reagents for the following conversion will be :

3 3

2 5

CH CHO CH CH OH|C H

(a) CH3MgCl, H2O/H+ (b) CH3CH2MgCl, H3O+

(c) (CH3)3 C–MgBr, H2O/H+ (d) CH3–CH2–CH2MgCl, H2O/H+

37. fuEu esa ls dkSulh jklk;fud fozQ;k djds ,uhlksy izkIr gksrk gS &

(a) CH3CHO; RMgX (b) C6H5OH; Neutral FeCl3

(c) C6H5OH; NaOH; CH3Br (d) C6H5–CH3, CH2COCl; AlCl3

Among the following sets of reactants which one will form Anisole?

(a) CH3CHO; RMgX (b) C6H5OH; Neutral FeCl3

(c) C6H5OH; NaOH; CH3Br (d) C6H5–CH3, CH2COCl; AlCl3

38. iQhukWy o ,FkkukWy esa foHksn djus ds fy, fdl vfHkdeZd dk iz;ksx gksxk&

(a) NaOH (aq.) (b) Neutral FeCl3

(c) H2/Ni (d) NaHCO3

Phenol and ethanol may be distinguished with which reagent:

(a) NaOH (aq.) (b) Neutral FeCl3

(c) H2/Ni (d) NaHCO3

39. fuEu esa ls dkSu ljyre ,sehuks vEy gS &

(a) fVªIVksisQu (b) ,sLisjkftu

(c) ,sysfuu (d) Xykbflu

XII-CHEMISTRY-E 15

Which one is the simplest amino acid :

(a) Tryptophan (b) Asparagine

(c) Alanine (d) Glycine

40. Br2–H2O }kjk vkWDlhdj.k djus ij Xywdksl nsrk gS &

(a) Xywdksfud ,flM (b) oSysfjd ,flM

(c) lSpfjd ,flM (d) XywdSfjd ,flM

On oxidation with Br2/H2O (Bromine water) glucose gets oxidized to :

(a) gluconic acid (b) valeric acid

(c) saccharic acid (d) glucaric acid

41. fiQfVx vfHkfØ;k dk iz;ksx fuEu esa ls fdl ;kSfxd dks cukus esa fd;k tkrk gS &

(a) csatksi+Qhuksu (b) MkbZfiQukbZy

(c) ,lhVksiQhuksu (d) Dyksjkscsathu

Fittig reaction can be used to prepare a compound :

(a) Benzophenone (b) Diphenyl

(c) Acetophenone (d) Chlorobenzene

42. lksuk (ijek.kqd vn~/ZO;kl ¾ 0.144 nm) iQyd dsafnzr ,dd lsy esa fozQLVyhd`r

gksrk gSA blds lsy ds dksj dh yEckbZ gksxh &

(a) 40.7 nm (b) 400.7 nm

(c) 0.407 nm (d) 0.0407 nm

Gold (atomic radius = 0.144 nm) crystallises in a face centred unit cell. The length of a side of the cell is:

(a) 40.7 nm (b) 400.7 nm

(c) 0.407 nm (d) 0.0407 nm

XII-CHEMISTRY-E 16

43. tc AgCl dks CdCl2 ds lkFk Mksi fd;k tkrk gS rks dkSu&lk nks"k mRiUu gksxk&

(a) 'kkWV~dh (b) izasQdsy

(c) v'kq¼ (d) varjkdk'kh

Which defect is produced when AgCl crystal is doped with CdCl2.

(a) Schottky (b) Frenkel

(c) Impurity (d) Interstitial

44. gSujh fu;e dh vko';d voLFkk@n'kk;sa gSa &

(a) xSl ,lksfl,lu ;k fMLlksfl;s'ku djsA

(b) xSl dk rki u T;knk de gks vkSj u T;knk vf/d gksA

(c) xSl fdlh dSfedy cnyko esa tk;sA

(d) mijksDr lHkhA

Henry’s Law is applicable in the conditions:

(a) The gas undergoes association or dissociation in the given solution.

(b) The pressure of the gas is not too high and temperature not too low.

(c) The gas undergoes any chemical change.

(d) All the above.

45. vfHkdFku (A) : tc NaCl dks ikuh esa feyk;k tkrk gS rks DoFkukad dk mUu;u

ns[kk tkrk gSA

dkj.k (R) : foy;u dk ok"i nkc de gksus ls DoFkukad dk mUu;u gksrk gSA

XII-CHEMISTRY-E 17

(a) A vkSj R nksuksa lgh gSa vkSj R, A ds fy, lgh Li"Vhdj.k gSA

(b) A vkSj R nksuksa lgh gSa vkSj R, A ds fy, lgh O;k[;k ugha djrk gSA

(c) A lgh dFku gS ysfdu R xyr dFku gSA

(d) A xyr dFku gS ysfdu R lgh dFku gSA

Assertion (A) : When NaCl is added to water an elevation in boiling point is observed.

Reason (R) : Lowering of vapour pressure of solution causes elevation in boiling point.

(a) A and R both are correct and reason (R) is correct explanation of A.

(b) A and R both are correct but reason (R) is not correct explanation of A.

(c) A is correct but R is wrong.

(d) A is wrong but R is correct.

46. vfHkdFku (A) : F2 esa F–F cU/ detksj gSA

dkj.k (R) : F-atom dk NksVk vkdkj gSA



(c) A lgh gS ysfdu R xyr gSA

(d) A xyr gS ysfdu R lgh gSA

Assertion (A) : In F2 molecule F-F bond is weak.

Reason (R) : Small size of F-atom.

XII-CHEMISTRY-E 18





47. vfHkdFku (A) : DyksjkscsUthu ukbVªs'ku ij m-ukbVªkscsathu nsrk gSA

dkj.k (R) : –NO2 group esVk&fMjsdfVax gSA





Assertion (A) : Nitration of chlorobenzene gives m-nitrochlorobenze.

Reason (R) : – NO2 group is m-directing.





48. vfHkdFku (A) : fdlh foy;u dh eksyyrk rkieku ds lkFk cnyrh gSA

dkj.k (R) : rkieku ds lkFk foy;u dk vk;ru cnyrk gSA

XII-CHEMISTRY-E 19





Assertion (A) : Molality of a solution changes with temperature.

Reason (R) : Volume of a solution changes with temperature.





49. vfHkdFku (A) : iQhukWy] p-ukbVªksiQhukWy ls de vEyh; gSA

dkj.k (R) : –NO2 lewg vkWFkksZ funsZ'kd gSaA





Assertion (A) : Phenol is weaker acid than p-nitrophenol.

Reason (R) : –NO2 group O-directing.

XII-CHEMISTRY-E 20





[k.M&lh (SECTION-C)

This section consists of 6 multiple choice questions with overall choice to attempt 5. In case more than desirable number of questions is attempted only first 5 will be considered for evaluation.

bl [kaM esa 6 cgqfodYih; iz'u gSa ftuesa oqQy fodYi 5 dk iz;kl djuk gSA ;fn

okafNr la[;k ls vf/d iz'uksa dk iz;kl fd;k tkrk gS rks ewY;kadu ds fy, dsoy

igys 5 ij fopkj fd;k tk,xkA

50. var%dsafnzr ,dd dksf"Bdk (chlhlh) lajpuk okys rRo esa 12.08×1024 dksf"Bdk

gSA bu dksf"Bdkvksa esa ijek.kqvksa dh la[;k gS &

(a) 12.08×1024 (b) 24.16×1024

(c) 48.38×1024 (d) 12.08×1023

An element having bcc structure has 12.08×1023 unit cells. The number of atoms in these cells is :

(a) 12.08×1024 (b) 24.16×1024

(c) 48.38×1024 (d) 12.08×1023

51. CH3–O–C(CH3)3 dks HI ds lkFk xeZ djus ij izkIr eq[; mRikn gksaxs &

(a) CH3–OH, (CH3)3C–I (b) CH3–I, (CH3)3 C–OH

(c) CH3–CH2–I, (CH3)3C–OH (d) C3H7–I, C2H5–OH

XII-CHEMISTRY-E 21

The major products that are formed by heating CH3–O–C(CH3)3 with HI are:

(a) CH3–OH, (CH3)3C–I (b) CH3–I, (CH3)3 C–OH

(c) CH3–CH2–I, (CH3)3C–OH (d) C3H7–I, C2H5–OH

52. bl vfHkfozQ;k esa D gS %

(a) izksisukWu (b) gsDlsu

(c) 2,3-MkbfeFkkbyC;wVsu (d) ,fyfyd czksekbM

alc.KOH HBr Na / ether3 2 2CH CH CH Cl B C D in this reaction D is:

(a) Propanone (b) Hexane

(c) 2,3 dimethylbutane (d) Allylic bromide

Case-I : x|ka'k i<+sa vkSj fuEufyf[kr iz'uksa ds mÙkj nsa (53&55)

,sls foy;u tks lHkh lkanzrkvksa ij jkmYV ds fu;e dk ikyu djrs gSa] vkn'kZ

foy;u dgykrs gSaA vkn'kZ foy;u ds nks vU; eq[; xq.k Hkh gksrs gSaA feJ.k cukus

ds fy, 'kq¼ vo;oksa dks fefJr djus ij feJ.k cukus dk ,saFkSYih ifjorZu rFkk

vk;ru ifjorZu 'kwU; gksrk gSA vFkkZr~

feJ.kH=0, feJ.kV=0

bldk rkRi;Z ;g gS fd vo;oksa dks fefJr djus ij mQ"ek dk mRltZu vFkok

vo'kks"k.k ugha gksrkA blds vfrfjDr foy;u dk vk;ru Hkh nksuksa vo;oksa ds

vk;ru ds ;ksx ds cjkcj gksrk gSA vkf.od Lrj ij foy;uksa ds vkn'kZ O;ogkj

dks vo;o A o B ds vè;;u }kjk le>k tk ldrk gSA 'kq¼ vo;oksa esa

varjkvkf.od vkd"kZ.k vU;ksU;fØ;k,a A-A vkSj B-B izdkj dh gksrh gSA tcfd

f}vaxh foy;uksa esa bu nksuksa vU;ksU;fozQ;kvksa ds vfrfjDr A-B izdkj dh

XII-CHEMISTRY-E 22

vU;ksU;fozQ;k,¡ Hkh mifLFkr gksaxhA ;fn A-A o B-B ds chp varjkvkf.od vkd"kZ.k

cy A-B ds leku gksa rks ;g vkn'kZ foy;u cukrk gSA

,d iw.kZ:is.k vkn'kZ foy;u dh laHkkouk de gksrh gS] ysfdu oqQN foy;u

O;ogkj esa yxHkx vkn'kZ gkrs gSaA

tc dksbZ foy;u lHkh lkanzrkvksa ij jkmYV ds fu;e dk ikyu ugha djrk rks og

vukn'kZ foy;u dgykrk gSA bl izdkj ds foy;uksa dk ok"inkc jkmYV ds fu;e

}kjk izkxqDr fd, x, ok"i nkc ls ;k rks vf/d gksrk gS ;k deA ;fn ;g vf/d

gksrk gS rks ;g foy;u jkmYV fu;e ls /ukRed foy;u iznf'kZr djrk gS vkSj

;fn ;g de gksrk gS rks ;g Í.kkRed fopyu iznf'kZr djrk gSA

Case-I – Read the passage and answer the following questions 53-55

The solutions which obey Raoult’s law over the entire range of concentration are known as ideal solutions. The ideal solutions have two other important properties. The enthalpy of mixing of the pure components to form the solution is zero and the volume of mixing is also zero, i.e.

mixH = 0, mix V = o

It means that no heat is absorbed or evolved when the components are mixed. Also, the volume of solution would be equal to the sum of volumes of the two components. At molecular level, ideal behaviour of the solutions can be explained by considering two components A and B. In pure components, the intermolecular attractive interactions will be of types A-A and B-B, whereas in the binary solutions in addition to these two interactions, A-B type of interactions will also be present. If the intermolecular attractive forces between the A-A and B-B are nearly equal to those between A-B, this leads to the formation of ideal solution. A perfectly ideal solution is rare but some solutions are nearly ideal in behaviour.

When a solution does not obey Raoult’s law over the entire range of concentration, then it is called non-ideal solution. The vapour pressure of

XII-CHEMISTRY-E 23

such a solution is either higher or lower than that predicted by Raoult’s law. If it is higher, the solution exhibits positive deviation and it is lower, it exhibits negative deviation from Raoult’s law.

53- ,d foy;u dks vkn'kZ foy;u dgk tkrk gS ;fn &

(a) jkmYV ds fue; dk ikyu ugha djrkA

(b) gsujh ds fue; dk ikyu djrk gSA

(c) jkmYV ds fue; dk ikyu djrk gSA

(d) okW;y ds fue; dk ikyu djrk gSA

A solution is said to be ideal if it :

(a) does not obey Raoult’s law (b) Obeys Henry’s law

(c) Obeys Raoult’s law (d) Obeys Boyle’s law

54. jkmYV ds fue; ls ?kukRed fopyu n'kkZus okyk mnkgj.k gSA

(a) HNO3 + H2O (b) CH3OH + H2O

(c) H2SO4 + H2O (d) CH3COCH3+CHCl3

Example showing positive deviation from Raoult’s law is :

(a) HNO3 + H2O (b) CH3OH + H2O

(c) H2SO4 + H2O (d) CH3COCH3+CHCl3

55. 114g vkWDVsu esa fdlh vok"i'khy foy; (eksyj&nzO;eku 40g mol–1) dh fdruh

ek=kk ?kksyh tk, fd vkWDVsu dk ok"i nkc ?kV dj ewy dk 80» jg tk,&

(a) 10 g (b) 20 g

(c) 30 g (d) 0.1 g

XII-CHEMISTRY-E 24

Calculate the mass of a non-volatile solute (molar mass 40 g mol–1) which should be dissolved in 114g octane to reduce its vapour pressure to 80%.

(a) 10 g (b) 20 g

(c) 30 g (d) 0.1 g

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No. of pages - 24 PRACTICE PAPER (2021-22) CLASS : XII