This document contains an unsolved chemistry practice test from 2004 with 50 multiple choice questions covering various topics in chemistry including quantum numbers, atomic structure, chemical bonding, acid-base reactions, solutions, equilibrium, electrochemistry, and coordination compounds. The questions require selecting the best answer from four choices given for each problem.

1. AIEEE–Past papersCHEMISTRY- UNSOLVED PAPER - 2004

2. SECTION – ASingle Correct Answer TypeThere are five parts in this question. Four choices are given for each part and one of them is correct. Indicate you choice of the correct answer for each part in your answer-book by writing the letter (a), (b), (c) or (d) whichever is appropriate

3. 01Problem Which of the following sets of quantum numbers is correct for an electron in 4f orbital ? n = 4, l = 3, m = + 4, s = + 1/2 n = 4, l = 4, m = - 4, s = - 1/2n = 4, l = 3, m = + 1, s = + 1/2n = 3, l = 2, m = -2, s = + ½

4. Problem02Consider the ground state of Cr atom (Z = 24). The numbers of electrons with the azimuthally quantum numbers, l = 1 and 2 are, respectively : 12 and 412 and 516 and 416 and 5

5. Problem03Which one of the following ions has the highest value of ionic radius ? Li+B3+O2-F-

6. Problem04The wavelength of the radiation emitted when in a hydrogen atom electron falls from infinity to stationary state 1, would be (Rydberg constant = 1.097 x 107 m-1) : 91 mm192 mm406 nm9.1 x 10-8 nm

7. Problem05The correct order of bond angles (smallest first) in H2S, NH3, BF3 and SiH4 is : H2S < SiH4 < NH3 < BF3NH3 < H2S < SiH4 < BF3H2S < NH3 < SiH4 < BF3H2S < NH3 < BF3 < SiH4

8. Problem06Which one of the following sets of ions represents the collection of isoelectromic species K+, Ca2+, Sc3+, Cl-Na+, Ca2+, Sc3+, F-K+, Cl-, Mg2+, Sc3+Na+, Mg2+, Al3+, Cl-(Atomic numbers F = 9, Cl = 17, Na = 11, Mg = 12, Al = 13, K = 19, Ca = 20, Sc = 21)

9. Problem07Among Al2O3, SiO2, P2O3 and SO2 the correct order of acid strength is : SO2 < P2O3 < SiO2 < Al2O3SiO2 < SO2 < Al2O3 < P2O3Al2O3 < SiO2 < SO2 < P2O3Al2O3 < SiO2 < P2O3 < SO2

10. Problem08The bond order in NO is 2.5 while that in NO+ is 3. Which of the following statements is true for these two species ? Bond length in NO+ is greater than in NOBond length in NO is greater than in NO+Bond length in NO+ is equal to that in NOBond length is unpredictable

11. Problem09The formation of the oxide ion O2- (g) requires first an exothermic and then an endothermic step as shown below.O(g) + e- = O-(g) ; ∆H0 = - 142 kJmol-1O(g)- + e- = O2-(g) ; ∆H0 = 844 kJ mol-1This is because : Oxygen is more electronegative Oxygen has high electron affinity O- ion will tend to resist the addition of another electron O- ion has comparatively larger size than oxygen atom

12. Problem10The sates of hybridization of boron and oxygen atoms in boric acid (H3BO3) are respectively : sp2 and sp2sp2 and sp3sp3 and sp2sp3 and sp3

13. Problem11Which one of the following has the regular tetrahedral structure ? XeF4SF4BF [Ni(CN)4]2-(Atomic numbers B = 5, S = 16, Ni = 28, Xe = 54)

14. Problem12Of the following outer electronic configurations of atoms, the highest oxidation state is achieved by which one of them ? (n - 1)d8 ns2(n - 1)d5 ns1(n - 1)d3 ns2(n - 1)d5 ns2

15. Problem13As the temperature is raised from 200C to 400C the average kinetic energy of neon atoms changes by a factor of which of the following ? a. ½b. c. 313/293d. 2

16. Problem14The maximum number of 900 angles between bond pair-bond pair of electrons is observed in : dsp3 hybridizationsp3d hybridizationdsp2 hybridizationsp3d2 hybridization

17. Problem15Which one of the following aqueous solutions will exhibit highest boiling point ? 0.01 M Na2SO40.01 M KNO30.015 M urea 0.015 M glucose

18. Problem16Which among the following factors is the most important in making fluorine the strongest oxidizing agent ? Electron affinity Ionization enthalpy Hydration enthalpy Bond dissociation energy

19. Problem17In van der Waals equation of state of the gas law, the constant ‘b’ is a measure of: Intermolecular repulsions Intermolecular attraction Volume occupied by the molecules Intermolecular collisions per unit volume

20. Problem18The conjugate base of H2PO is : PO43-P2O5H3PO4HPO42-

21. Problem196.02 x 1020 molecules of urea are present in 100 mL of its solution. The concentration of urea solution is : 0.001 M0.01 M0.02 M0.1 M(Avogadro constant, NA = 6.02 x 1023 mol-1)

22. Problem20To neutralize completely 20 mL of 0.1 M aqueous solution of phosphorous acid (H3PO3), the volume of 0.1 M aqueous KOH solution required is : 10 mL20 mL40 mL60 mL

23. Problem21For which of the following parameters the structural isomers C2H5OH and CH3OCH3 would be expected to have the same values ? (Assume ideal behaviour) : Heat of vaporization Vapour pressure at the same temperature Boiling points Gaseous densities at the same temperatures and pressure

24. Problem22Which of the following liquid pairs shows a positive deviation from Raoult’s law ? Water - hydrochloric acid Benzene - methanol Water - nitric acid Acetone - chloroform

25. Problem23Which one of the following statements is false ? Raoult’s law states that the vapour pressure of a component over a solution is proportional to its mole fraction The osmotic pressure ( ) of a solution is given by the equation = MRT, where M is the molarity of the solution The correct order of osmotic pressure for 0.01 M aqueous solution of each compound is BaCl2 > KCl > CH3COOH > sucrose Two sucrose solutions of same molality prepared in different solvents will have the same freezing point depression

26. Problem24What type of crystal defect is indicated in the diagram below ? Na+, Cl-, Na+, Cl-, Na+, Cl- Frenkel defect Schottky defect Interstitial defect Frenkel and Schottky defects

27. Problem25An ideal gas expands in volume from 1 x 10-3 to 1 x 10-2 m3 at 300 K against a constant pressure of 1 x 105 Nm-2. The work done is : - 900 J- 900 kJ270 kJ900 kJ

28. Problem26In hydrogen-oxygen fuel cell, combustion of hydrogen occurs to : Generate heat Create potential difference between the two electrodes Produce high purity water Remove adosred oxygen from electrode surfaces

29. Problem27In a first order reaction, the concentration the reactant, decreases frm 0.8 M to 0.4 M in 15 minutes. The time taken for the concentration to change from 0.1 M to 0.025 M is : 30 min15 min7.5 min60 min

30. Problem28What is the equilibrium expression for the reaction P4(s) + 5O2(g) P4O10(s) ? a.b.c. KC = [O2]5d.

31. Problem29For the reaction, CO(g) + Cl2 (g) COCl2(g), the Kp/Kc is equal to: a.1/RTb. RTc. d. 1.0

32. Problem30The equilibrium constant for the reactions N2(g) + O2 (g) 2NO(g) at temperature T is 4 x 10-4. The value Kc for the reaction : at the same temperature is : 2.5 x 102504 x 10-40.02

33. Problem31The rate equation for the reaction 2A + B-> C is fond to be : are = k [A] [B].The correct statement in relation to this reaction is that the : Unit of k must be s-1t1/2 is a constant rate of formation of C is twice the rate of disappearance of A value of k is independent of the initial concentrations of A and B

34. Problem32Consider the following E0 values : Eo Fe3+/Fe2+ = +0.77VEoSn2+/Sn = -0.14 VUnder standard conditions the potential for the reaction Sn(s) + 2Fe3+(aq) 2Fe2+ (aq) + Sn2+ (aq) is : 1.68 V1.40 V0.91 V0.63 V

35. Problem33The molar solubility(in mol L-1) of a sparingly soluble salt MX4 is ‘s’ the corresponding solubility product is Ksp. s is given in terms of Ksp by the relation : s = (Ksp/128)1/4s = (128 Ksp)1/4s = (256 Ksp)1/5s = (Ksp/256)1/5

36. Problem34The standard e.m.f. of a cell, involving one electron change is found to be 0.591 V at 250C. The equilibrium constant of the reaction is (F = 96,500 C mol-1, R = 8.314 JK-1 mol-1) : 1.0 x 1011.0 x 1051.0 x 10101.0 x 1030

37. Problem35The enthalpies of combustion of carbon and carbon monoxide are -393.5 and -283 kJ mol-1 respectively. The enthalpy of formation of carbon monoxide per mole is110.5 kJ -110.5 kJ -676.5 kJ 676.5 kJ

38. Problem36The limiting molar conductivities ^0 for NaCl, KBr and KCl are 126, 152 and 150 S cm2 mol-1 respectively. The ^0 for NaBr is : 128 S cm2 mol-1176 S cm2 mol-1278 S cm2 mol-1302 S cm2 mol-1

39. Problem37In a cell that utilizes the reaction Zn(s) + 2H (aq) -> Zn2+ (aq) + H2 (g) addition of H2SO4 to cathode compartment, will : Lower the E and shift equilibrium to the left Lower the E and shift the equilibrium to the right Increase the E and shift the equilibrium to the right Increase the E and shift the equilibrium to the left

40. Problem38Which one of the following statements regarding helium is incorrect ? It is used to fill gas balloons instead of hydrogen because it is lighter and non-inflammable It is used as a cryogenic agent for carrying out experiments at low temperatures It is used to produce and sustain powerful superconducting magnets It is used in gas-cooled nuclear reactors

41. Problem39Identify the correct statement regarding enzymes : Enzymes are specific biological catalysts that can normally function at very high temperatures (T ~ 1000 K).Enzymes are normally heterogeneous catalysts that are very specific in their action Enzymes are specific biological catalysts that cannot be poisoned Enzymes are specific biological catalysts that possess well defined active sites.

42. Problem40One mole of magnesium nitride on the reaction with an excess of water gives: One mole of ammonia One mole of nitric acid Two moles of ammonia Two moles of nitric acid

43. Problem41Which one of the following ores is best concentrated by froth-floatation method ? Magnetite CassiteriteGalena Malachite

44. Problem42Beryllium and aluminum exhibit many properties which are similar. But, the two elements differ in : Exhibiting maximum covalency in compounds Forming polymeric hydridesForming covalent halides Exhibiting amphoteric nature in their oxides

45. Problem43Aluminum chloride exists as dimmer, Al2Cl6 in solid state as well as in solution of non-polar solvents such as benzene, when dissolved in water, it gives : Al3+ + 3Cl-[Al(H2O)6]3+ + 3Cl-[Al(OH)6]3- + 3HClAl2O3 + 6HCl

46. Problem44The soldiers of Napolean army while at Alps during freezing winter suffered a serious problem as regards to the tin buttons of their uniforms. White metallic tin buttons got converted to grey powder. This transformation is related to : A change in the crystalline structure of tinAn interaction with nitrogen of the air at very low temperaturesA change in the partial pressure of oxygen in the airAn interaction with water vapour contained in the humid air

47. Problem45The values for Cr, Mn, Fe and Co are -0.41, + 157, + 0.77 and + 1.97 V respectively. For which one of these metals the change in oxidation state from + 2 to + 3 is easiest ? CrMnFeCo

48. Problem46Excess of KI reacts with CuSO4 solution and the Na2S2O3 solution is added to it. Which of the statements is incorrect for this reaction ? Cu2I2 is formed CuI2 is formed Na2S2O3 is oxidized Evolved I2 is reduced

49. Problem47Among the properties (A) reducing (B) oxidizing (C) complexing, the set of properties shown by CN- ion towards metal species is : A, BB, CC, AA, B, C

50. Problem48The co-ordination number of a central metal atom in a complex is determined by The number of ligands around a metal ion bonded by sigma bonds The number of ligands around a metal ion bounded by pi-bonds The number of ligands around a metal ion bounded by sigma and pi-bonds both The number of only anionic ligands bonded to the metal ion

51. Problem49 Which one of the following complexes is an outer orbital complex ? [Fe(CN)6]4-[Mn(CN)6]4-[Co(NH3)6]3+[Ni(NH3)6]2+(Atomic numbers Mn = 25, Fe = 36, Co = 27, Ni = 28)

52. Problem50Co-ordination compounds have great importance in biological systems. In this context which of the following statements is incorrect ? Chlorophylls are green pigments in plants and contain calcium Haemoglobin is the red pigment of blood and contains iron Cyanocobalamin is vitamin B12 and contains cobalt Carboxypeptidase-A is an enzyme and contains zinc

53. Problem51Cerkum (Z = 58) is an important member of the lanthanoids. Which of the following statements about cerium is incorrect ? The common oxidation states of cerium are + 3 and + 4The + 3 oxidation state of cerium is more stable than the + 4 oxidation state The + 4 oxidation state of cerium is not known in solutions Cerium (IV) acts as an oxidizing agent

54. Problem52Which one of the following has largest number of isomers ? [Ru (NH3)4 Cl2]+[Co (NH3)5Cl]2+[Ir(PR3)2 H(CO)]2+[Co(en)2Cl2]+(R = alkyl group, en = ethylenediamine)

55. Problem53The correct order of magnetic moments (spin only values in B.M.) among the following is [MnCl4]2- > [CoCl4]2- > [Fe(CN6)]4-[MnCl4]2-> [Fe(CN6)]4-> [CoCl4]2-Fe(CN6)]4- > [MnCl4]2- > [CoCl4]2-[Fe(CN6)]4-> [CoCl4]2-> [MnCl4]2-(Atomic numbers Mn = 25, Fe = 26, Co = 27)

56. Problem54Consider the following nuclear reactions : The number of neutrons in he element L is :142144140146

57. Problem55The half-life of a radioisotope is four hours. If the initial mass of the isotope was 200 g. The mass remaining after 24 hours undecided is : 1.042 g2.084 g3.125 g4.167 g

58. Problem56The compound formed in the positive test for nitrogen with the Lasaigne solution of an organic compound is : Fe4[Fe(CN)6]3Na3[Fe(CN)6]Fe[Fe(CN)]3Na4[Fe(CN)6NOS]

59. Problem57The ammonia evolved from the treatment of 0.30 g of an organic compound of the estimation of nitrogen was passed in 100 mL, of 0.1 M sulphuric acid. The excess of acid required 20 mL of 0.5 M sodium hydroxide solution of complete neutralization. The organic compound is : AcetamideBenzamideUrea Thiourea

60. Problem58Which one of the following has the minimum boiling point ? n-butane 1-butyne 1-butene Isobutene

61. Problem59The IUPAC name of the compound 3,3-dimethyl-1-hydroxy cyclohexane1,1-dimethyl-3-hydroxy cyclohexane3,3-dimethyl-1-cyclohexanol1,1-dimethyl-3-cyclohexanol

62. Problem60Which one of the following does not have sp2hybridised carbon ? Acetone Acetic acid AcetonitrileAcetamide

63. Problem61Which of the following will have a meso-isomer also ? 2-chlorobutane2,3-dichlorobutane2, 3-dichloropentane 2- hydroxypropanoic acid

64. Problem62Rate of the reaction Is fastest when Z is : ClNH2OC2H5OCOCH3

65. Problem63Amongst the following compounds, the optically active alkane having lowest molecular mass is :

66. Problem64Consider the acidity of the carboxylic acids:PhCOOHo-NO2C6H4COOHp-NO2C6H4COOHm-NO2C6H4COOH

67. Problem65which of the following is the strongest base ?

68. Problem66Which base is present in RNA but not in DNA ? UracilCytosine Guanine Thymine

69. Problem67The compound formed on heating chlorobenzene with chloral in the presence of concentrated sulphuric acid is : GammexeneDDTFreon Hexachloroethane

70. Problem68On mixing ethyl acetate with aqueous sodium chloride, the composition of the resultant solution is : CH3COOC2H5 + NaClCH3COONa + C2H5OHCH3COCl + C2H5OH + NaOHCH3Cl + C2H5COONa

71. Problem69Acetyl bromide reacts with excess of CH3MgI followed by treatment with a saturated solution of NH4Cl gives : Acetone Acetamide2-methyl-2-propanolAcetyl iodide

72. Problem70Which one of the following is reduced with zinc and hydrochloric acid to give the corresponding hydrocarbon ? Ethyl acetate Acetic acid AcetamideButan-2-one

73. Problem71Which one of the following undergoes reaction with 50% sodium hydroxide solution to give the corresponding alcohol and acid ? Phenol BenzaldehydeButananlBenzoic acid

74. Problem72Among the following compounds which can be dehydrated very easily ?

75. Problem73Which of the following compounds is not chiral ? 1-chloropentane 2-chloropentane 1-chloro-2-methyl pentane 3-chloro-2-mehtyl pentane

76. Problem74Insulin production and its action in human body are responsible for the level of diabetes this compound belongs to which of the following categories ? A co-enzyme AhormoneAn enzyme An antibiotic

77. Problem75The smog is essentially caused by the presence of : O2 and O3O2 and N2Oxides of sulphur and nitrogen O3 and N2

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