General Organic Chemistry PYQs Set 3 (PDF)

Set 3 of 25 · Questions 61-90 of 724

In the print window choose “Save as PDF”. The file prints without a web address or date line.

Mere Teacher · Previous Year Questions JEE Main Chemistry · General Organic Chemistry · Set 3 (Q61-90)
Scan or visit mereteacher.com for free PYQ practice, timed CBT tests, step-by-step solutions and BroBot AI. Answers and solutions are free with a sign-up.
61. $The decreasing order of electrical conductivity of the following aqueous solutions is : 0.1 M Formic acid (A), 0. I M Acetic acid (B), 0.1 M Benzoic acid (C) .$ (1) $A > C > B$ (2) $C > B > A$ (3) $A > B > C$ (4) $C > A > B$ 62. $In Lassaigne's test for halogens, it is necessary to remove X and Y from the sodium fusion extract, if nitrogen and sulphur are present. This is done by boiling the extract with Z . Identify X, Y and Z .$ (1) $X = NaNO_{3}, Y = Na_{2} SO_{4}, Z = conc. HNO_{3}$ (2) $X = NaNH_{2}, Y = NaSH, Z = conc. HCl$ (3) $X = Na_{2} NO_{2}, Y = NaSO_{3} H, Z = conc. H_{2} SO_{4}$ (4) $X = NaCN, Y = Na_{2} S, Z = conc. HNO_{3}$ 63. $The correct order of increasing bond length of C-H, C-O, C-C and C=C is :$ (1) $C-H < C=C < C-O < C-C$ (2) $C-C < C=C < C-O < C-H$ (3) $C-O < C-H < C-C < C=C$ (4) $C-H < C-O < C-C < C=C$ 64. $The number of σ and π bonds present in Pent-1-en-4-yne is$ (1) $3, 10$ (2) $9, 4$ (3) $4, 9$ (4) $10, 3$ 65. $Consider thiol anion (RSΘ) and alkoxy anion (ROΘ). Which of the following statement is correct ?$ (1) $RSΘ is less basic but more nucleophilic than ROΘ.$ (2) $RSΘ is more basic and more nucleophilic than ROΘ.$ (3) $RSΘ is more basic but less nucleophilic than ROΘ.$ (4) $RSΘ is less basic and less nucleophilic than ROΘ.$ 66. $Sodium fusion extract of aniline when heated with ferrous sulphate solution and then acidified with concentrated H_{2} SO_{4} from which of the following complexes?$ (1) $(Fe (CN)_{6})^{4}$ (2) $Fe_{4} (Fe (CN)_{6})_{3} \cdot x H_{2} O$ (3) $[Fe (SCN)]^{2 +}$ (4) $(Fe (CN)_{5} NOS)^{4 -}$ 67. $Which of the following is used as an antiknocking material?$ (1) $Glyoxal$ (2) $Freon$ (3) $TE.L.$ (4) $Ethyl alcohol$ 68. $In Carius method, 0.75 g of an organic compound gave 1.2 g of barium sulphate, find percentage of sulphur (molar mass 32 g mol^{- 1}). Molar mass of barium sulphate is 233 g mol^{- 1} .$ (1) $10.30 %$ (2) $16.48 %$ (3) $21.97 %$ (4) $4.55 %$ 69. $A miscible mixture of C_{6} H_{6} + CHCl_{3} can be separated by$ (1) $sublimation$ (2) $distillation$ (3) $filtration$ (4) $crystallisation.$ 70. $The correct statement among the following, for a "chromatography" purification method is :$ (1) $Organic compounds run faster than solvent in the thin layer chromatographic plate.$ (2) $R_{f} is an integral value.$ (3) $R_{f} of a polar compound is smaller than that of a non-polar compound.$ (4) $Non-polar compounds are retained at top and polar compounds come down in column chromatography.$ 71. $In Lassaigne sodium fusion test, N and S of an organic compounds are converted into$ (1) $NaCN$ (2) $Na_{2} S$ (3) $NaCNS$ (4) $NaNS$ 72. $In case of substituted aniline, the group which derreases the basic strength is$ (1) $- OCH_{3}$ (2) $- CH_{3}$ (3) $- NH_{2}$ (4) $- C_{6} H_{5}$ 73. $In Carius method 0.2425 g of an organic compound gave 0.5253 g silver chloride. The percentage of chlorine in the organic compound is$ (1) $34.79 %$ (2) $37.57 %$ (3) $87.65 %$ (4) $53.58 %$ 74. $In 1 C H_{2} = 2 C = 3 CH - 4 C H_{3} molecule, the hybridization of carbon 1, 2, 3 and 4 respectively are:$ (1) $sp², sp, sp², sp³$ (2) $sp², sp², sp², sp³$ (3) $sp², sp³, sp², sp³$ (4) $sp³, sp, sp³, sp³$ 75. $The difference in energy between the actual structure and the lowest energy resonance structure for the given compound is$ (1) $electromeric energy$ (2) $resonance energy$ (3) $ionization energy$ (4) $hyperconjugation energy$ 76. $Match List I with List II List I (Compound) A. Ethanol B. Phenol C. m-Nitrophenol D. p-Nitrophenol List II (pK value) I. 10.0 II. 15.9 III. 7.1 IV. 8.3 Choose the correct answer from the options given below :-$ (1) $A-I, B-II, C-III, D-IV$ (2) $A-IV, B-I, C-II, D-III$ (3) $A-III, B-IV, C-I, D-II$ (4) $A-II, B-I, C-IV, D-III$ 77. $25 g of an unknown hydrocarbon upon burning produces 88 g of C O_{2} and 9 g of H_{2} O . This unknown hydrocarbon contains:$ (1) $20 g of carbon and 5 g of Hydrogen$ (2) $22 g of carbon and 3 g of Hydrogen$ (3) $24 g of carbon and 1 g of Hydrogen$ (4) $18 g of carbon and 7 g of Hydrogen$ 78. $Which of the following statement is correct for paper chromatography?$ (1) $Water present in the pores of the paper forms the stationary phase.$ (2) $Paper sheet forms the stationary phase.$ (3) $Water present in the mobile phase gets absorbed by the paper which then forms the stationary phase.$ (4) $Paper and water present in its pores together form the stationary phase.$ 79. $The organic chloro compound, which shows complete stereochemical inversion during an S_{N} 2 reaction, is:$ (1) $(C H_{3})_{3} CCl$ (2) $(C H_{3})_{2} CHCl$ (3) $C H_{3} Cl$ (4) $(C_{2} H_{5})_{2} CHCl$ 80. $In Kjeldahl's method for estimation of nitrogen, CuSO_{4} acts as :$ (1) $Reducing agent$ (2) $Catalytic agent$ (3) $Hydrolysis agent$ (4) $Oxidising agent$ 81. $The dipole moments of CHCl_{3}, CCl_{4} and C H_{4} are in the order:$ (1) $CHC l_{3} > CC l_{4} = C H_{4}$ (2) $CHC l_{3} > CC l_{4} > C H_{4}$ (3) $CC l_{4} > CHC l_{3} > C H_{4}$ (4) $CC l_{4} = C H_{4} > CHC l_{3}$ 82. $Reactivity order of halides for dehydrohalogenation is$ (1) $R - F > R - Cl > R - Br > R - I$ (2) $R - I > R - Br > R - Cl > R - F$ (3) $R - I > R - Cl > R - Br > R - F$ (4) $R - F > R - I > R - Br > R - Cl$ 83. $For which of the following, Kjeldahl's method is not used for the estimation of nitrogen? I. Aniline II. Azobenzene III. Nitrobenzene IV. Pyridine$ (1) $II, III, IV$ (2) $II, III only$ (3) $III, IV only$ (4) $I, III, IV$ 84. $Which purification technique is used for high boiling organic liquid compound (decomposes near its boiling point)?$ (1) $Simple distillation$ (2) $Steam distillation$ (3) $Fractional distillation$ (4) $Reduced pressure distillation$ 85. $Which of the following fertilizers has the highest nitrogen percentage?$ (1) $Ammonium sulphate$ (2) $Calcium cyanamide$ (3) $Urea$ (4) $Ammonium nitrate$ 86. $Which of the following is the correct order of decreasing SN2 reactivity ?$ (1) $RCH2X > R3CX > R2CHX$ (2) $RCH2X > R2CHX > R3CX$ (3) $R3CX > R2CHX > RCH2X$ (4) $R2CHX > R3CX > RCH2X$ 87. $0.2 g of an organic compound was subjected to estimation of nitrogen by Dumas method in which volume of N_{2} evolved (at STP) was found to be 22.400 mL. The percentage of nitrogen in the compound is____. [nearest integer](Given: Molar mass of N_{2} is 28 m o l^{- 1} . Molar volume of N_{2} at STP : 22.4 L)$ 88. $In Dumas method for estimation of nitrogen, 0.50 g of an organic compound gave 70 mL of nitrogen collected at 300 K and 715 mm pressure. The percentage of nitrogen in the organic compound is____% . (Aqueous tension at 300 K is 15 mm).$ 89. $The separation of two coloured substances was done by paper chromatography. The distances travelled by solvent front, substance A and substance B from the base line are 3.25 cm. 2.08 cm and 1.05 cm. respectively. The ratio of R_{f} values of A to B is______$ 90. $An organic compound is subjected to chlorination to get compound A using 5.0g of chlorine. When 0.5g of compound A is reacted with A g N O_{3} [Carius Method], the percentage of chlorine in compound A is when it forms 0.3849 g of AgCl. (Round off to the Nearest Integer)(Atomic masses of Ag and Cl are 107.87 and 35.5 respectively)$