june chemistry

82 Chemistry today | June ’10

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1. The ratio of the molar amounts of H2S needed to precipitate the metal ions from 20 ml each of 1 M Cd(NO3)2 and 0.5 M CuSO4 is

(a) 1 : 1 (b) 2 : 1 (c) 1:2 (d) indefinite

2. Which one of the following will give a linear plot at constant pressure ?

(a) V vs T (b) V vs 1/T (c) T vs 1/T (d) None of these

3. Suggest two transitions in the atomic spectrum of hydrogen for which the wave number ratio is 108 : 7

(a) FirstLymanandfirstBrackettransition (b) First and second Lyman series transition (c) FirstLymanandfirstBalmertransition (d) FirstLymanandfirstPaschentransition

4. A diatomic molecule has a dipole moment of 1.2 D. If the bond distance is 1Å, what percentage of electronic charge exists on each atom ?

(a) 12% of e (b) 19% of e (c) 25% of e (d) 29% of e

5. The phase diagram for the pure solvent (solid lines) and the solution (non-volatile solute) (dashed lines) are recorded below:

The quantity indicated by L inthefigureis (a) DP (b) DTf

(c) Kf ⋅m (d) Kb·m

6. One mole of an anhydrous salt AB dissolves in water with the evolution of 21.0 J mol–1 of heat. If the heat of hydration of AB is – 29.4 J mol–1,

then the heat of dissociation of the hydrated salt AB is

(a) 50.4 J mol–1 (b) 8.4 J mol–1

(c) –50.4 J mol–1 (d) –8.4 J mol–1

7. The equilibrium :P4(g) + 6Cl2(g) 4PCl3(g)

isattainedbymixingequalmolesofP4 and Cl2 in an evacuated vessel. Then at equilibrium

(a) [Cl2]>[PCl3] (b) [Cl2]>[P4] (c) [P4] > [Cl2] (d) [PCl3]>[P4]

8. At 18°C, the solubility product of AgCl is 1.8 × 10–10. In the solution, the value of [Ag+] is 4 × 10–3 mol/litre. The value of [Cl–] to precipitate AgCl from the solution should be greater than

(a) 4.5 × 10–8 mol/litre (b) 7.2 × 10–12 mol/litre (c) 4.0 × 10–3 mol/litre (d) 4.5 × 10–7 mol/litre

9. In a reaction, 4 moles of electrons are transferred to one mole of HNO3. The possible product obtained due to reduction is

(a) 0.5 mole of N2 (b) 0.5 mole of N2O (c) 1 mole of NO2 (d) 1 mole of NH3

10. An electric current is passed through silver voltmeter connected to a water voltmeter. The cathode of the silver voltmeter is 0.108 g more at the end of the electrolysis. The volume of oxygen evolvedatSTPis

(a) 56 cm3 (b) 550 cm3

(c) 5.6 cm3 (d) 11.2 cm3.

11. In a second order reaction, first order with respect to each reactant A and B, which one of the following reactant mixtures will provide the highest initial rate ?

(a) 0.1 mol of A and 0.1 mol of B in 0.1 litre solvent

(b) 0.2 mol of A and 0.2 mol of B in 0.1 litre solvent

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(c) 1.0 mol of A and 1.0 mol of B in 1 litre solvent

(d) 0.1 mol of A and 0.1 mol of B in 0.2 litre solvent

12. A certain nuclide has half life period of 30 min. If a sample containing 6 × 1010 atoms is allowed to decay for 90 min, how many atoms will remain?

(a) 2 × 1010 atoms (b) 4.5 × 109 atoms (c) 7.5 × 109 atoms (d) 1.5 × 109 atoms

13. Which one of the following characteristics is not correct for physical adsorption ?

(a) Adsorption increases with increase in temperature

(b) Adsorption is spontaneous (c) Bothenthalpyandentropyofadsorptionare

negative (d) Adsorption on solids is reversible

14. Which of the following does not represent the correct order of the property indicated ?

(a) Sc3+ > Cr3+ > Fe3+ > Mn3+ : Ionic radii (b) Sc < Ti < Cr < Mn : Density (c) Mn2+ > Ni2+ < Co2+ < Fe2+ : Ionic radii (d) FeO<CaO>MnO>CuO:Basicnature

15. Match List I with List II and select the correct answer using the codes given below the lists :

ListI ListII I. Cyanide process A. Ultrapure Ge II. Floatationprocees B. Pineoil III. Electrolytic reduction C. Extraction of Al IV. Zonerefining D. ExtractionofAu Codes : (a) I-C,II-A,III-D,IV-B (b) I-D,II-B,III-C,IV-A (c) I-C,II-B,III-D,IV-A (d) I-D,II-A,III-C,IV-B

16. Which of the following statements is not correct?

(a) H2O2 oxidises Fe(II) to Fe(III) (b) H2O2 can be obtained by electrolysis of dil.

H2SO4 (c) H2O2 reduces Mn(VII) to Mn(II) (d) H2O2 isaweakbase

17. In the Down's process for the manufacture of sodium by electrolysis of molten NaCl, the cathode and the anode are separated by a diaphragm because

(a) it increases the yield of Na and Cl2 (b) itpreventsthereactiontakingplacebetween

NaOH and Cl2

(c) it prevents the mixing of NaOH and NaCl (d) it prevents the reaction between Na and

Cl2

18. The correct order of increasing ionic character is

(a) BeCl2 < MgCl2 < CaCl2<BaCl2 (b) BeCl2 < MgCl2<BaCl2 < CaCl2 (c) BeCl2<BaCl2 < MgCl2 < CaCl2 (d) BaCl2 < CaCl2 < MgCl2<BeCl219. A deep brown gas is formed by mixing two

colourless gases which are (a) NO2 and O2 (b) N2O and NO (c) NO and O2 (d) NH3 and HCl

20. The correct order of increasing C—O bond length of CO, CO3

2–, CO2 is (a) CO3

2– < CO2 < CO (b) CO2 < CO32– < CO

(c) CO < CO32– < CO2 (d) CO < CO2 < CO3

2–

21. The following acids have been arranged in the order of decreasing acid strength. Identify the correct order.

(I).ClOH,(II).BrOH,(III).IOH (a) I > II > III (b) II > I > III (c) III > II > I (d) I > III > II

22. In acidic medium, KMnO4 oxidises FeSO4 solution. Which of the following statements is correct ?

(a) 10 ml of 1 N KMnO4 solution oxidises 10 ml of 5 N FeSO4 solution

(b) 10 ml of 1 M KMnO4 solution oxidises 10 ml of 5 M FeSO4 solution

(c) 10 ml of 1 M KMnO4 solution oxidises 10 ml of 1 M FeSO4 solution

(d) 10 ml of 1 N KMnO4 solution oxidises 10 ml of 0.1 M FeSO4 solution

23. In the complexes [Fe(H2O)6]3+, Fe(CN)6]3–, [Fe(C2O4)3]3– and [FeCl6]3–, more stability is shown by

(a) [Fe(H2O)6]3+ (b) [Fe(CN)6]3–

(c) [Fe(C2O4)3]3– (d) [FeCl6]3–

24. IUPACnameofthecompound

(a) 4-Iso-propyl-6-methyloctane (b) 3-Methyl-5-(1′-methylethyl)octane (c) 3-Methyl-5-iso-propyloctane (d) 6-Methyl-4-(1′-methylethyl)octane.


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25. Two organic compounds A and B, both containing only C and H yield, on analysis, the same percentage composition by weight:C = (12/13) × 100% and H = (1/13) × 100%AdecolourisesBr2 water but B does not. Identify A and B.

(a) A = C2H2, B = C6H6 (b) A = C6H6, B = C2H2 (c) A = C2H4, B = C2H6 (d) A = C2H2, B = C3H8

26. What is the order of dehydrohalogenation of the following compounds in presence of strong base?

(a) 1 > 2 > 3 > 4 (b) 2 > 4 > 3 > 1 (c) 4 > 2 > 1 > 3 (d) 1 > 2 > 4 > 3

27. Relative stabilities of the following carbocation will be in order

(a) I < II < III < IV (b) IV < III < II < I (c) IV < II < III < I (d) II < IV < III < I.

28.

(a) (b)

(c) (d)

29. Phenolgivessym-tribromophenol when treated with bromine in aqueous solution but only o- and p-bromophenols in CCl4 solution because

(a) in aqueous solution bromine is ionised. (b) in aqueous solution, phenol exists in

equilibrium with phenoxide ion which has moreactivatingeffect.

(c) in CCl4,theelectrophilicityofBr2 increases. (d) in CCl4, the other positions of benzene ring

areblockedbythesolvent.

30. The correct order of reactivity of group in the following compounds is

(a) CH3CHO > (CH3)2CO > C2H5COCH3 (b) C2H5COCH3 > (CH3)2CO < CH3CHO (c) (CH3)2CO > CH3CHO > C2H5COCH3 (d) (CH3)2CO > C2H5COCH3 > CH3CHO

31. An ester (A) with molecular formula, C9H10O2 was treated with excess of CH3MgBrand thecomplex so formed was treated with H2SO4 to giveanolefin(B). Ozonolysis of (B)gaveaketonewith molecular formula C8H8O which shows +ve iodoform test. The structure of (A) is

(a) C6H5COOC2H5 (b) C6H5COOC6H5 (c) CH3OCH2COC6H5 (d) p-CH3O—CO—C6H4—COCH3

32. The correct order of basic strength of the following are

(a) 1 > 2 > 3 > 4 (b) 4 > 2 > 3 > 1 (c) 3 > 4 > 2 > 1 (d) 3 > 2 > 4 > 1.

33. Whichofthefollowingalkenesismostreactivetowards cationic polymerization ?

(a) CH2 CHCH3 (b) CH2 CHCl (c) CH2 CHC6H5 (d) CH2 CHCOOCH3

34. Identifythefinalproductinthereactionsequence

C6H12O6 (glucose) (A)

(B) (C) (a) a-methyl glycoside (b) n-hexane (c) n-heptane (d) b-methyl cyanohydrin.

35. Two binary solutions have the same molarity. Which of the following statements is true?

(a) Equal volumes of the two solutions contain equal number of solute molecules.

(b) Equal weights of the two solutions contain equal number of solute molecules.

(c) The two solutions must have the same molality

(d) The two solutions must have the same mole fraction.


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36. A bulb emits light of l = 4500 Å. The bulb is rated150Vand8%energy isemittedas light.Thenumberofphotonsemittedpersecondis

(a) 27.2 × 1018 (b) 29.4 × 102

(c) 27.2 × 106 (d) 2.72 × 109

37. TheelectronicconfigurationofelementsA, B and C are [He]2s1, [Ne]3s1 and [Ar]4s1 respectively. Which one of the following order is correct for IE1(inkJmol–1) of A, B and C ?

(a) A > B > C (b) C > B > A (c) B > C > A (d) C > A > B

38. When N2+ is formed from N2, bond order ...... and

when O2+ is formed from O2, bond order ........

(a) increases, increases (b) decreases, decreases (c) increases, decreases (d) decreases, increases.

39. InaflaskofvolumeV litres, 0.2 mol of oxygen, 0.4 mol of nitrogen, 0.1 mol of ammonia and 0.3 mol of helium are enclosed at 27°C. If the total pressure exerted by these non-reacting gases is one atmosphere, the partial pressure exerted by nitrogen is

(a) 1 atm (b) 0.1 atm (c) 0.2 atm (d) 0.4 atm

40. If DG = DH – TDS and DG = DH + T d G

dT P

( )∆

then variation of EMF of a cell, with temperature T, is given by

(a) ∆SnF

(b) −∆SnF

(c) ∆HnF

(d) ∆GnF

41. One mole of a compound AB reacts with one mole of compound CD according to the equation AB + CD → AD + CB. When equilibrium had been established it was found that 3/4 mole each of reactants AB and CD have been converted to AD and CB. There is no change in volume. The equilibrium constant of the reaction is

(a) 9/16 (b) 7/9 (c) 16/9 (d) 9

42. pH of 0.1 M solutions of the following increase in the order

(a) NaCl < NH4Cl < NaCN < HCl (b) HCl < NH4Cl < NaCl < NaCN (c) NaCN < NH4Cl < NaCl < HCl (d) HCl < NaCl < NaCN < NH4Cl.

43. In the reaction, 4Fe + 3O2 4Fe3+ + 6O2– which of the following statement is incorrect?

(a) It is a redox reaction

(b) Metallic iron is a reducing agent (c) Fe3+ is an oxidising agent (d) Metallic iron is reduced to Fe3+.

44. An element has a body-centred cubic (bcc) structure with a cell edge of 288 pm. The density of the element is 7.2 g/cm3. How many atoms are present in 208 g of the element?

(a) 6.02 × 1024 atoms (b) 12.09 × 1023 atoms (c) 24.16 × 1023 atoms (d) 29.88 × 1024 atoms

45. For the reaction, 3BrO– BrO3

–+2Br–

in alkaline aqueous solution, the value of thesecond order (in BrO–) rate constant at 80°C for the rate law –D[BrO–]/Dt was found to be 0.056 L mol–1 s–1. Rate constant when the rate law iswrittenforD[BrO3

–]/Dt, is (a) 0.056 L mol–1 s–1

(b) 0.056/3 L mol–1 s–1

(c) 0 056 2

3. ×

L mol–1 s–1

(d) 0 056

2.

L mol–1 s–1

46. Calculate the freezing point of an aqueous solution containing 10% by mass of glucose, 5% by mass of urea and 1% by mass of KCl.

K f (H2O) = 1.86 K/m. (a) –2.25°C (b) 0°C (c) –3.03°C (d) –1.63°C.

47. 84210

82206

24Po Pb + He→

From the above nuclear reaction, predict the position of polonium in the periodic table ( lead belongs to group IVA)

(a) IIA (b) IVB (c) VIB (d) VIA.

48. On adding AgNO3 solution to KI solution, a negatively charged colloidal sol will be formed in which of the following conditions?

(a) 100 mL of 0.1 M AgNO3 + 100 mL of 0.1 M KI (b) 100 mL of 0.1 M AgNO3 + 50 mL of 0.2 M KI (c) 100 mL of 0.2 M AgNO3 + 100 mL of 0.1 M KI (d) 100 mL of 0.1 M AgNO3 + 100 mL of 0.15 M KI

49. If is is thenFe |Fe Fe |Fe Fe |Fe2+ 3+ 3+ 2+E x E x E° ° °

1 2, , will be

(a) 3x2 – 2x1 (b) x2 – x1 (c) x2 + x1 (d) 2x1 + 3x2

50. The correct order of decreasing polarisability of ion is

(a) Cl–,Br–, I–, F– (b) F–, I–,Br–, Cl–

(c) I–,Br–, Cl–, F– (d) F–, Cl–,Br–, I–


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51. Which does not contain isoelectronic species? (a) PO SO ClO4

342

4− − −, , (b) CN N C− −, ,2 2

2

(c) SO CO NO32

32

3− − −, , (d) BO CO NO3

332

3− − −, ,

52. The formation of the oxide ion O2–requiresfirstan exothermic and then an endothermic step as shown below :

O(g) + e → O–(g); DH°=–142kJmol–1

O–(g) + e → O2–

(g); DH°=844kJmol–1

This is because (a) O– ion has comparatively larger size than

oxygen atom (b) oxygenhashighelectronaffinity (c) O– ion will tend to resist the addition of

another electron (d) oxygen is more electronegative

53. The group containing oxides that cannot be reduced by carbon to give the respective metal is

(a) Cu2O, SnO2 (b) Fe2O3 (c) Na2O, Al2O3 (d) PbO,Fe2O3

54. The amount of H2O2 present in 1 L of 1.5 N H2O2 solution is (a) 2.5 g (b) 25.5 g (c) 3.0 g (d) 8.0 g

55. Acidified solution of sodium thiosulphate is unstable because in thiosulphate

(a) the sulphur atoms are at unstable oxidation state of +2

(b) the two sulphur atoms are at different oxidation states of +6 and –2

(c) the S – S bonds are unstable bonds (d) thio compounds contain sulphur in zero

oxidation state

56. Beryllium showsdiagonal relationshipwithaluminium. Which of the following similarity is incorrect?

(a) B e 2C l i k e A l 4C 3 y i e l d s m e t h a n e o n hydrolysis

(b) BelikeAlisrenderedpassivebyHNO3 (c) Be(OH)2 likeAl(OH)3 is basic (d) B e f o rm s b e r y l l a t e s a nd A l f o rm s

aluminates

57. Borazoleisobtainedbyreactionof (a) NH3+B2H6 in 2 : 1 ratio (b) NH3+B2H6 in 1 : 2 ratio (c) NH3+B2H6 in 1 : 4 ratio (d) NH3+B2H6 in 4 : 1 ratio

58. The correct order of decreasing ionic nature of lead dihalides is

(a) PbF2>PbCl2>PbBr2>PbI2 (b) PbF2>PbBr2>PbCl2>PbI2

(c) PbF2<PbCl2>PbBr2<PbI2 (d) PbI2<PbBr2<PbCl2<PbF2

59. Which of the following is arranged in the increasing order of enthalpy of vaporization ?

(a) NH3,PH3, AsH3 (b) AsH3,PH3, NH3 (c) NH3, AsH3,PH3 (d) PH3, AsH3, NH3

60. Hydrolysis of one mole of peroxodisulphuric acid produces

(a) two moles of sulphuric acid (b) two moles of peroxomonosulphuric acid (c) one mole of sulphuric acid and one mole of

peroxomonosulphuric acid (d) one mole each of sulphuric acid, peroxomono-

sulphuric acid and hydrogen peroxide

61. The set with correct order of acidity is (a) HClO < HClO2 < HClO3 < HClO4 (b) HClO4 < HClO3 < HClO2 < HClO (c) HClO < HClO4 < HClO3 < HClO2 (d) HClO4 < HClO2 < HClO3 < HClO.

62. Which of the following pairs is coloured in aqueous solution ?

(a) Sc3+, Co2+ (b) Ni2+, Cu+

(c) Ni2+, Ti3+ (d) Sc3+, Ti3+

63. The complex ion [Cu(NH3)4]2+ has (a) tetrahedralconfigurationwithoneunpaired

electron (b) squareplanarconfigurationwithoneunpaired

electron (c) tetrahedralconfigurationwithallelectrons

paired (d) squareplanarconfigurationwithallelectrons

paired

64. Addition of HI on double bond of propene yields iso-propyl iodide as major product. It is because the addition proceeds through

(a) more stable carbocation (b) more stable carbanion (c) more stable free radical (d) homolysis

65. 0.759 g of a silver salt of a dibasic organic acid on ignitionleft0.463gmetallicsilver.Theequivalentweight of acid is(a) 70 (b) 108 (c) 60 (d) 50

66. Which one is correct for the given change ?

(a) The product formed is trans-2-methyl-1-

cyclopentanol


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(b) The product formed is

(c) The addition is syn addition (d) All of the above.

67. Correct order of reactivity for halides is (a) Vinyl chloride >Allyl chloride >Propyl

chloride (b) Propyl chloride >Vinyl chloride >Allyl

chloride (c) Allyl chloride >Propyl chloride >Vinyl

chloride (d) none of the above

68. HBr reacts with CH2 CH––OCH3 under anhydrous conditions at room temperature to give

(a) CH3CHO and CH3Br (b) BrCH2CHO and CH3OH (c) BrCH2––CH2––OCH3 (d) H3C––CHBr––OCH3

69. Identify Z in the series,

(a) CH3.CO.CH2COONa (b) (CH3CO)2O (c) CH2Cl.CO.O.COCH3 (d) CHCl2.CO.O.COCH3

70. A sequential reaction may be performed as represented below:

The appropriate reagent for step (3) is (a) brominealone (b) bromineandalkali (c) HBr (d) P2O5

71. Identify X in the series,

(a) (b)

(c) (d)

72. In the reaction,

the intermediate 'X' is (a) phthalic anhydride (b) phthalic acid (c) o-xylene (d) benzoic acid

73. Which of the following can possibly be used as analgesic without causing addiction and any modification?

(a) Morphine (b) N-acetyl-para-aminophenol (c) Diazepam (d) Tetra hydrocatenol

74. Which one of the following pairs is not correctly matched?

(a) Terylene : condensation polymer of terephthalic acid and ethylene glycol

(b) Teflon:thermallystablecrosslinkedpolymerof phenol and formaldehyde

(c) Perspex:ahomopolymerofmethyl methacrylate (d) Synthetic rubber : a copolymer of butadiene

and styrene

75. The major products (P, Q) in the given reaction are

(a)

(b)

(c)

(d)

76. Which of the following is correctly arranged in order of increasing weight?

(a) 0.625 g of Fe < 0.0105 equivalent of H2C2O4·2H2O < 6.0 × 1021 atoms of Zn < 0.006 g atom of Ag

(b) 0.625 g of Fe < 6.0 × 1021 atoms of Zn < 0.006 g atom of Ag < 0.0105 equivalent

of H2C2O4·2H2O (c) 0.0105 equivalent of H2C2O4·2H2O < 0.006 g

atom of Ag < 6.0 × 1021 atoms of Zn < 0.625 g of Fe


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(d) 0.0105 equivalent of H2C2O4·2H2O < 0.625 g of Fe < 0.006 g atom of Ag < 6.0 × 1021 atoms of Zn.

77. The volume of 0.0168 mol of O2 obtained by decomposition of KClO3 and collected by displacement of water is 428 mL at a pressure of 754 mm Hg at 25°C. The pressure of water vapour at 25°C is

(a) 18 mm Hg (b) 20 mm Hg (c) 22 mm Hg (d) 24 mm Hg

78. For the manufacture of ammonia by the reaction N + 3H 2NH +21.9kcal,2 2 3 the favourable conditions are

(a) low temperature, low pressure and catalyst (b) low temperature, high pressure and catalyst (c) high temperature, low pressure and catalyst (d) high temperature, high pressure and

catalyst.

79. Thevan’tHofffactorfor0.1MBa(NO3)2 solution is 2.74. The degree of dissociation is

(a) 91.3 % (b) 74 % (c) 87 % (d) 100 %

80. The standard reduction potential of Zn and Ag in water at 298 K are,

Zn2+ + 2e– Zn; E° = – 0.76 V and Ag+ + e– Ag; E° = + 0.80 V Whichofthefollowingreactionstakesplace? (a) Zn2+

(aq) + Ag+(aq) Zn(s) + Ag(s)

(b) Zn(s) + Ag(s) Zn2+(aq) + Ag+

(aq)

(c) Zn2+(aq) + 2Ag(s) 2Ag+

(aq) + Zn(s)

(d) Zn(s) + 2Ag+(aq) Zn2+

(aq) + 2Ag(s).

81. Among Al2O3, SiO2,P2O3 and SO2 the correct order of acid strength is

(a) SO2<P2O3 < SiO2 < Al2O3

(b) Al2O3 < SiO2<P2O3 < SO2

(c) Al2O3 < SiO2 < SO2<P2O3

(d) SiO2 < SO2 < Al2O3<P2O3

82. When a substance A reacts with water it produces a combustible gas B and a solution of a substance C in water. When another substance D reacts with this solution of C, it also produces the same gas B even on reaction with dilute sulphuric acid at room temperature. A imparts a deep golden yellowcolour toasmokeless flameofBunsenburner. A, B, C and D respectively are

(a) Na, H2, NaOH and Zn (b) K, H2, KOH and Al

(c) Ca, H2, Ca(OH)2 and Sn (d) CaC2, C2H2, Ca(OH)2 and Fe.

83. When orthoboric acid (H3BO3) is heated, the residueleftis

(a) boron (b) metaboric acid (c) boric anhydride (d) borax.

84. Which of the following statements is correct with respect to the property of elements with increase in atomic number in the carbon family (group 14)?

(a) Their metallic character decreases (b) The stability of +2 oxidation state increases (c) Their ionization energy increases (d) Their atomic size decreases.

85. During the formation of the N2O4 dimer from two molecules of NO2, the odd electrons, one in each of the nitrogen atoms of the NO2 molecules, get paired to form a

(a) weakN–Nbond, twoN–Obondsbecomeequivalent and the other two N–O bonds become non equivalent

(b) weakN–NbondandallthefourN–Obondsbecome equivalent

(c) weakN–NbondandallthefourN–Obondsbecome non equivalent

(d) strong N–N bond and all the four N–O bonds become equivalent.

86. Oxygen is more electronegative than sulphur. Yet H2S is acidic while H2O is neutral. This is because

(a) water is a highly associated compound (b) molecular mass of H2S is more than that of

H2O (c) H2S is gaseous under ordinary conditions

while H2O is a liquid (d) H–SbondisweakerthanH–Obond.

87. SO2 acts as temporary bleaching agent but Cl2 acts as permanent bleaching agent. Why ?

(a) Cl2 bleaches due to reduction but SO2 due to oxidation

(b) Cl2 bleaches due to oxidation but SO2 due to reduction

(c) Both(a)and(b) (d) None of these.

88. Potassiummanganate (K2MnO4) is formed when

(a) chlorine is passed into aqueous KMnO4 solution


9

(b) manganese dioxide is fused with potassium hydroxide in air

(c) formaldehyde reacts with potassium permanganate in presence of a strong alkali

(d) potassium permanganate reacts with concentrated sulphuric acid.

89. The formula o f the complex potass ium trichloroethylene platinate(II) is

(a) K[PtCl3(C2H4)] (b) K2[PtCl3(C2H4)3] (c) K4[PtCl3(C2H4)] (d) K3[Pt2Cl3(C2H4)3].

90. 0.765 g of an acid gives 0.535 g of CO2 and 0.138 g of H2O. Then the ratio of the percentage of carbon and hydrogen is

(a) 19 : 2 (b) 18 : 11 (c) 70 : 17 (d) 1 : 7.

91. Among the following, the least stable resonance structure is

(a) (b)

(c) (d)

92. AdditionofBr2 on cis-butene-2 gives (a) a racemic mixture of 2,3-dibromobutane (b) meso form of 2,3-dibromobutane (c) dextro form of 2,3-dibromobutane (d) laevo form of 2,3-dibromobutane.

93.

[A] and [B] are respectively (a) cis, trans-2-butene (b) both trans-2-butene (c) trans-cis-2-butene (d) both cis-2-butene.

94. Which is least reactive towards nucleophilic substitution (SN2)?

(a) CH2 CH – CH2Cl

(b)

(c)

(d) CH3 – CH(Cl)CH3.

95. Which of the following will not be soluble in sodium carbonate solution?

(a) (b)

(c) (d)

96. Tautomerism is not exhibited by

(a) (b)

(c) (d)

97. Z in the following sequence of reactions is

(a) (b)

(c) (d)

98. Sucrose on reacting with conc. H2SO4 gives (a) arabinose and SO2 (b) glucose and fructose (c) carbon and H2O (d) carbon, H2O and SO2

99. The essential condition for an indicator to be used in a titration is

(a) pKIn = pKa of solution at equivalence point (b) pKIn = pKb of solution at equivalence point (c) pKIn = pH of solution at equivalence point (d) pKIn = pKa + pKb of solution at equivalence

point.

100.A substance on treatment with dil. H2SO4 liberates a colourless gas which produces (i) turbidity with barytawaterand(ii)turnsacidifieddichromatesolution green. The reaction indicates the presence of

(a) CO32– (b) S2–

(c) SO32– (d) NO2

–.

CHEMISTRY TODAY | June ’10 81

7. (i) 2Au+11HCl+3HNO32HAuCl4+3NOCl+6H2O

(ii) C+4HNO3(conc.) CO2+4NO2+2H2O

LeveL – iv

1. FeSO4·(NH4)2SO4·6H2O(i) FeSO4·(NH4)2SO4·6H2O+BaCl2

BaSO4↓ whiteppt.(ii) FeSO4·(NH4)2SO4·6H2O+NaOH NH3↑ Alkalinegas

2. X = NaHCO3 A = CO2B = H2O Y = Na2CO3

2NaHCO3 Na2CO3+H2O+CO2

3. (i) Sincethemixtureissolubleinwatertogivestronglyalkalinesolution, itmustcontainNaOHasoneoftheconstituents.

(ii) Sincetheaqueoussolutiongivesprecipitatewithdil.HCl,whichdissolves inexcessofdil.HCl,itmustcontainzincsalt.

ThusthemixtureconsistsofZnSO4andNaOHwhichexplainsallthegivenreactions.Reactions:(i) ZnSO NaOH Na ZnO +Na SO 2H O2 2 2 4

Soluble24 4+ → +

ZnSO NaOH Na ZnO +Na SO 2H O2 2 2 4Soluble

24 4+ → +

(ii) Na2ZnO2+2HCl 2NaCl+Zn(OH)2↓ Zn(OH)2+2HCl ZnCl2+2H2O Soluble

4. A=FeSO4·7H2O B=FeSO4

C =Fe(NO)SO4 D=Fe2O3

E =SO2 F=SO3

5. X=KHCO3 A=CO2

B =H2O Y=K2CO3

Z =BaCO3

6. A = FeSO4 BandC=SO2andSO3

D= Fe2O3 E = BaSO4.

7. A = (NH4)2Cr2O7 B = Cr2O3

C = N2 D= Mg3N2 E = NH3

Reactions:

8. A = KO2B=K2SO4C=K2SO4·Al2(SO4)3·24H2O

9. A = O3 B = KO3 C = O2

10. A = NH4NO3 B = N2O C = H2OReactions:

11. A = FeSO4·7H2O B = Fe2O3 C = SO2 D= SO3

E = FeCl3 F = SG = FeCl2 H= Fe(SCN)3

12. A = CuS B = Cu2I2(white)Reactions:CuSO4+H2S CuS+H2SO4 (A)[CuSO4+2KI CuI2+K2SO4]×22CuI2 Cu2I2+I2

2CuSO4+4KI Cu2I2+2K2SO4+I2 (white) (B)ThusthetransitionmetalionisCu2+.

anSweRS tO Objective aSSignmentSLeveL – i

1. (b) 2. (b) 3. (b) 4. (d) 5. (a)6. (d) 7. (d) 8. (a)

LeveL – ii

1. (c) 2. (a) 3. (d) 4. (d) 5. (c)6. (c) 7. (b) 8. (c)

mmanSweR keyS Of SeLf diagnOStic teSt

1.(b)2.(a)3.(d)4.(c)5.(d)6.(b)7.(c)8.(a)9.(b)10.(c)11.(b)12.(c)13.(a)14.(a)15.(b)16.(d)17.(d)18.(a)19.(c)20.(d)21.(a)22.(b)23.(c)24.(b)25.(a)26.(b)27.(c)28.(a)29.(b)30.(a)31.(a)32.(d)33.(c)34.(c)35.(a)36.(a)37.(a)38.(d)39.(d)40.(a)41.(d)42.(b)43.(d)44.(c)45.(b)46.(c)47.(d)48.(d)49.(a)50.(c)51.(c)52.(c)53.(c)54.(b)55.(b)56.(c)57.(a)58.(a)59.(d)60.(c)61.(a)62.(c)63.(b)64.(a)65.(a)66.(d)67.(c)68.(d)69.(b)70.(b)71.(b)72.(b)73.(b)74.(b)75.(c)76.(b)77.(d)78.(b)79.(c)80.(d)81.(b)82.(a)83.(c)84.(b)85.(b)86.(d)87.(b)88.(b)89.(a)90.(a)91.(a)92.(a)93.(a)94.(c)95.(c)96.(a)97.(b)98.(d)99.(c)100.(c)

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