CHEMISTRY 51. An S N 2 reaction at an asymmetric carbon of a compound always gives

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1 CHEMISTRY 51. An S N reaction at an asymmetric carbon of a compound always gives an enantiomer of the substrate a product with opposite optical rotation a mixture of diastereoisomers (d) a single stereoisomer 5. IUPAC name of HC CH=CH CH CH=CH is CH CH CH CH 3 4 butyl,5 hexadien 1 al 5 vinyloct 5 en 8 al 5 vinyloct 3 en 1 al (d) 3 butyl 1,4 hexadien 6 al 53. CH on ozonolysis gives + HCH CH CHCH 3 (d) None of these 54. Hydroxylation of C CH in presence of H S 4 /HgS 4 gives: CCH 3 CH CH CCH 3 (d) CH CH 55. Which of the following carbocation is most stable? CH 3 H N C C CH (d) C CH 3 C C CH 3 AlCl 3 products. ne of the products formed in the reaction will be C CH CH 3 C H (d) CH 3 C H 57. C C CH 3 HgS H S 4 4 major product will be C CH CH 3 H CH CH CH CH 3 C C CH 3 cis butene both and Na Liq. NH 3 product will be CH C CH 3 H (d) CH CH CH 3 trans butene (d) none of these

2 59. The correct order of rate of S N 1 reaction for alkyl halide is 3 > > 1 3 < < 1 1 < > 3 (d) 3 > The appropriate reagent for the following transformation is CCH 3 CH CH 3 H H Zn Hg, HCl NH NH, KH LiAlH 4 (d) HI, P With rise in temperature; viscosity of a liquid increases remains constant decreases (d) may increase or decrease 6. The heat of formation of C and C are 6.4 kcal and 94.6 kcal respectively. Heat of combustion of carbon monoxide will be +6.4 kcal 68. kcal 10.6 kcal (d) +5.8 kcal 63. The difference between heat of reaction at constant pressure and constant volume of the following reaction would be C 6 H 6 (l) + 15 (g) 1C (g) + 6H (l) at 5 C in kj mol 1 is (d) The reaction, ½H (g) + AgCl(s) H + (aq) + Cl (aq) + Ag(s), occurs in the galvanic cell: Ag(s) AgCl(s) KCl (solution) AgN 3 (solution) Ag(s) Pt H (g) HCl (solution) AgN 3 (solution) Ag(s) Pt H (g) HCl (solution) AgCl(s) Ag(s) (d) Pt H (g) KCl (solution) AgCl(s) Ag(s) 65. In the formation of sulphur trioxide by contact process, S + S 3, the rate of reaction was measured as d[ ] = mol L 1 s 1 dt The rate of reaction expressed in terms of S 3 will be mol L 1 s mol L 1 s mol L 1 s 1 (d) mol L 1 s Which of the following statements is not correct? Boric acid is a very weak monobasic acid. Boric acid contains planar B 3 units, which are bonded together through hydrogen bonds forming a layer structure. Boric acid is used as a food preservative. (d) Boric acid is tribasic acid. 67. Sodium is not ordinarily observed in the + oxidation state because of its high first ionization potential. high second oxidation potential. high ionic radius. (d) high electronegativity.

3 68. Which of the following ions has the highest reduction potential? Li + Na + K + (d) Rb xidation of Cr 3+ in acid solution forms Cr Cr 4 Cr 7 (d) Cr+ 70. In solid CuS 4.5H, copper is coordinated to five water molecules. four water molecules. one sulphate ion. (d) one water molecule. 71. The compound, which reacts fastest with Lucas reagent at room temperature is H (d) H H 7. The critical temperature of a substance is defined as the temperature above which the substance decomposes. the temperature above which a substance can exist only as a gas. melting point of the substance. (d) boiling point of the substance. 73. Correct set of four quantum numbers for the valence (outermost) electrons of rubidium 5, 0, 0, +1/ 5, 1, 0, + 1 H 5, 1, 1, +1/ (d) 6, 0, 0, Which one is a colligative property? Boiling point smotic pressure Vapour pressure (d) Freezing point mol of A is mixed with. mol of B and the mixture is kept in a one litre flask till the equilibrium, A + B C + D is reached. At equilibrium 0. mol of C is formed. The equilibrium constant of the above reaction is (d) In which of the following compounds, the oxidation number of iodine is fractional? IF 7 I 3 IF 5 (d) IF The rate law expression for the hypothetical reaction A + 3B C is dx = k[a] [B] dt The order of reaction is 1 3 (d) An element belongs to Group 15 and third period. Its electronic configuration will be 1s s p 3 1s s p 6 3s 3p 3

4 1s s p (d) 1s s p 6 3s 3p 79. Which of the following is an electron deficient compound? NH 3 NH H BCl 3 (d) H 3 N BCl A dehydrating agent commonly used in the laboratory is MgC 3 CaF CaCl (d) MgF 81. Which of the following represents baryta? Ba Ba(H) BaC 3 (d) Ba(N 3 ) 8. The outer electronic configuration of copper is 3d 10 4s 1 3d 9 4s 3d 10 4s 0 (d) 3d 10 4s 83. Tautomerism is not exhibited by C 6 H 5 CH=CHH 84. In the compound CH =CH CH C CH, the C C 3 bond is of the type sp sp sp sp sp sp 3 (d) sp sp Which of the following compounds will give a yellow precipitate with I and alkali? 3 hydroxy pentene Acetophenone Methyl acetate (d) Acetamide (d) 86. Alkaline hydrolysis of an ester is called: neutralization polymerisation 87. Which one is a colligative property? Boiling point smotic pressure esterification (d) saponification Vapour pressure (d) Freezing point 88. The number of effective atoms per unit cell in a simple cubic, face centered cubic and body centred cubic are.respectively 1, 4, 4, 1,, 4, 1 (d) 4, 8, 89. Absence of one cation and one anion in a crystal lattice is ionic defect Frenkel defect Schottky defect (d) interstitial defect 90. Which of the following expression is correct in case of a CsCl unit cell (edge length, a)? a r c + r a = a r c + r a =

5 r c + r a = 3a a (d) r c + r a = 91. In a face centred cubic system the distance d between the nearest neighbours is given by (a = edge length) d = a d = a d = 3 a (d) d = 9. The rate constant for the reaction: N 5 4N + is s 1. If the rate at a given time is mol L 1 s 1. Then concentration of N 5 at that time is (d) The atomic weight of a trivalent element is 7. Its electrochemical equivalent is (d) ml each of 0.5 N NaH, N/5 HCl and N/10 H S 4 are mixed together. The resulting solution will be acidic neutral alkaline (d) none of these 95. C(s) + (g) C (g) ; H = r C(g) + ½ (g) C (g) ; H = s The heat of formation of C is r s s r r s (d) r + s 96. Energy of electron in the third orbit of Bohr s H atom is 13.6 ev 34 ev 1.5 ev (d) none of the three 97. For the combustion reaction at 98 K, Ag(s) + ½ (g) Ag (s) which of the following relation will be true? H = U H > U H < U (d) H and U bear no relation with each other 98. If in a standard hydrogen electrode half cell, H + (aq) + e H (g) (1 atm), hydrogen ion concentration is reduced to 10 1 M by adding a base, then the emf will be V V V (d) V 99. The plot of log k vs T 1 helps to calculate Energy of activation Rate constant of the reaction rder of the reaction (d) Energy of activation as well as the frequency factor The halide, which will not react with benzene in presence of anhydrous AlCl 3, is a

6 CH 3 CHClCH 3 C 6 H 5 Cl C 6 H 5 CH Cl (d) CH 3 CH CH Cl

TEST OF CHEMISTRY. 1. 2H 2 O H 3 O + + OH, Kw = at 25 C, hence Ka is (a) (b) (c) (d)

TEST OF CHEMISTRY. 1. 2H 2 O H 3 O + + OH, Kw = at 25 C, hence Ka is (a) (b) (c) (d) TEST OF CHEMISTRY 1. 2H 2 O H 3 O + + OH, Kw = 1 10 14 at 25 C, hence Ka is (a) 1 10 14 (b) 5.55 10 13 (c) 18 10 17 (d) 1.00 10 7 2. Identify the correct order of acidic strengths of CO 2, CuO, CaO, H