Surface Chemistry PYQs Set 3 (PDF)

Set 3 of 8 · Questions 61-90 of 227

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Mere Teacher · Previous Year Questions NEET Chemistry · Surface Chemistry · Set 3 (Q61-90)
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61. $Which of the following statements is/are not correct?(A) Adsorption is accompanied by decrease in enthalpy as well as decrease in entropy of the system.(B) Gases, which can react strongly with adsorbent show chemisorption.(C) When the value of the slope of the Freundlich isotherm is non-zero, adsorption is independent of pressure.(D) Gold number of potato starch is 0.15 .$ (1) $A, D$ (2) $B, C$ (3) $A, C$ (4) $C, D$ 62. $For micelle formation, which of the following statements are correct? (A) Micelle formation is an exothermic process. (B) Micelle formation is an endothermic process. (C) The entropy change is positive. (D) The entropy change is negative.$ (1) $A and D only$ (2) $A and C only$ (3) $B and C only$ (4) $B and D only$ 63. $The basic principle of Cottrell's precipitator is$ (1) $neutralisation of charge on colloidal particles$ (2) $scattering of light$ (3) $Le-Chatelier's principle$ (4) $peptisation.$ 64. $Which of the following is the most effective in causing coagulation of ferric hydroxide solution?$ (1) $KCl$ (2) $KNO_{3}$ (3) $K_{2} SO_{4}$ (4) $K_{3} (Fe (CN)_{6})$ 65. $Haemoglobinand gold sol are examples of:$ (1) $positivelyand negatively charged sols, respectively$ (2) $Positively charged sols$ (3) $Negatively charged sols$ (4) $Negatively and positively charged sols, respectively.$ 66. $The gold numbers of gelatin, haemoglobin and sodium acetate are 5 \times 10^{- 3}, 5 \times 10^{- 2} and 7 \times 10^{- 1}, respectively. The protective actions will be in the order$ (1) $Gelatin < haemoglobin < sodium acetate$ (2) $Gelatin > haemoglobin > sodium acetate$ (3) $Haemoglobin > gelatin > sodium acetate$ (4) $Sodium acetate > gelatin > haemoglobin$ 67. $Statements about Enzyme Inhibitor Drugs are given below : (A) There are Competitive and Non-competitive inhibitor drugs. (B) These can bind at the active sites and allosteric sites. (C) Competitive Drugs are allosteric site blocking drugs. (D) Non-competitive Drugs are active site blocking drugs. Choose the correct answer from the options given below:$ (1) $(A), (D) only$ (2) $(A), (C) only$ (3) $(A), (B) only$ (4) $(A), (B), (C) only$ 68. $According to hardy-schultz rule, Coagulation value or flocculation value \propto Fe (OH)_{3} sol is:$ (1) $K_{2} Cr O_{4} > K_{3} [Fe (CN)_{6}] > KN O_{3} > KBr = Al C l_{3}$ (2) $K_{3} [Fe (CN)_{6}] > K_{2} Cr O_{4} > KN O_{3} = KBr = AlC l_{3}$ (3) $K_{3} [Fe (CN)_{6}] < K_{2} Cr O_{4} < KN O_{3} = KBr = AlC l_{3}$ (4) $KN O_{3} > KBr = K_{2} Cr O_{4} > AlC l_{3} = K_{3} [Fe (CN)_{6}]$ 69. $Which one of the following statements is true?$ (1) $Saponification of oil yields a diol$ (2) $Drying of oil involves hydrolysis$ (3) $Addition of antioxidant to oil minimizes rancidity$ (4) $Refining of oil involves hydrogenation$ 70. $The correct statements about Zeolites are (I) They are good shape selective catalysts (II) They contain Al-O-Si framework (III) They are not found in nature (IV) They are used as catalysts for cracking hydrocarbons, in petrochemical industry$ (1) $I & II only$ (2) $II & III only$ (3) $III & IV only$ (4) $I, II & IV only$ 71. $Which property of colloids is not dependent on the charge on colloidal particles?$ (1) $Coagulation$ (2) $Electrophoresis$ (3) $Electro‐osmosis$ (4) $Tyndall effect$ 72. $Assertion (A) : Animal skins are colloidal in natureReason (R) : Animal skin has positively charged particles.$ (1) $Both (A) and (R) are correct and (R) is the correct explanation of (A)$ (2) $Both (A) and (R) are correct and (R) is not the correct explanation of (A)$ (3) $(A) is correct but (R) is incorrect$ (4) $(A) is incorrect but (R) is correct "$ 73. $2.0 g of activated charcoal is added to 100 mL of 0.5 M acetic acid (molar mass 60 g mol^{- 1}), shaken well and filtered. The concentration of solution is reduced to 0.4 M . How many grams of acetic acid is adsorbed on charcoal per gram?$ (1) $0.1$ (2) $0.2$ (3) $0.3$ (4) $0.15$ 74. $Freundlich adsorption isotherm fails at which of the following condition?$ (1) $High temperature$ (2) $Low temperature$ (3) $High pressure$ (4) $Low pressure$ 75. $The stability of a lyophobic colloid is due to$ (1) $adsorption of covalent molecules on the colloid$ (2) $the size of the particles$ (3) $the charge on the particles$ (4) $Tyndall effect.$ 76. $The colloidal solution used to treat stomach disorders is$ (1) $Silver sol$ (2) $Antimony sol$ (3) $Milk of magnesia$ (4) $Gold sol$ 77. $Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: The diameter of colloidal particles in solution should not be much smaller than wavelength of light to show Tyndall effect. Reason R: The light scatters in all directions when the size of particles is large enough. In the light of the above statements, choose the correct answer from the options given below:$ (1) $Both A and R are correct and R is the correct explanation of A$ (2) $A is true but R is false$ (3) $Both A and R are correct but R is NOT the correct explanation of A$ (4) $A is false but R is true$ 78. $Critical Micelle concentration for a soap solution is 1.5 \times 10^{- 4} mol L^{- 1} . Micelle formation is possible only when the concentration of soap solution in mol L^{- 1} is$ (1) $2.0 \times 10^{- 3}$ (2) $4.6 \times 10^{- 5}$ (3) $7.5 \times 10^{- 5}$ (4) $1.1 \times 10^{- 4}$ 79. $A 42.12% (w/v) solution of NaCl causes precipitation of a certain sol in 10 hours. The coagulating value of NaCl for the sol is [Given : Molar mass : Na = 23.0 g m o l^{- 1}; Cl = 35.5 g m o l^{- 1}]$ (1) $36 mmol L^{- l}$ (2) $36 mol L^{- 1}$ (3) $1440 m o l L^{- 1}$ (4) $1440 mmol L^{- 1}$ 80. $Which of the following is a correct statement ?$ (1) $Brownian motion destabilises sols.$ (2) $Any amount of dispersed phase can be added to emulsion without destabilising it.$ (3) $Mixing two oppositely charged sols in equal amount neutralises charges and stabilises colloids.$ (4) $Presence of equal and similar charges on colloidal particles provides stability to the colloidal solution$ 81. $For precipitating Fe (OH)_{3} sol, the best precipitating agent is$ (1) $Na_{2} SO_{4}$ (2) $Cr (OH)_{3}$ (3) $Al (OH)_{3}$ (4) $Na_{3} (Fe (CN)_{6})$ 82. $The electrolyte having maximum flocculation value for Agl / Ag^{+} sol is$ (1) $Na_{2} S$ (2) $Na_{3} PO_{4}$ (3) $NaCl$ (4) $Na_{2} SO_{4}$ 83. $Methylene blue, from its aqueous solution, is adsorbed on activated charcoal at 25° C. For this process, the correct statement is$ (1) $The adsorption requires activation at 25°C.$ (2) $The adsorption is accompanied by a decreases in enthalpy.$ (3) $The adsorption increases with increase of temperature.$ (4) $The adsorption is irreversible.$ 84. $The no. of positively and negatively charged sols respectively in the following are TiO_{2}, blood, CdS, Cu, Ag, Clay, SiO_{2}, Fe_{2} O_{3} .$ (1) $5,3$ (2) $3,5$ (3) $6,2$ (4) $4,4$ 85. $If x gram of gas is adsorbed by m gram of adsorbent at pressure P, the plot of log \frac{x}{m} versus log P is linear. The slope of the plot is: (n and k are constants and n > 1)$ (1) $2 k$ (2) $log k$ (3) $n$ (4) $\frac{1}{n}$ 86. $Which one of the following does not involve coagulation?$ (1) $Formation of delta regions$ (2) $Peptization$ (3) $Treatment of drinking water by potash alum$ (4) $Clotting of blood by the use of ferric chloride$ 87. $The macromolecular colloids of the following are I. Starch solution III. Synthetic detergent II. Sulphur sol IV. Synthetic rubber$ (1) $I, II$ (2) $II, III$ (3) $III, IV$ (4) $I, IV$ 88. $which property of colloidal solution is independent of charge on the colloidal particles?$ (1) $Electroosmosis$ (2) $Tyndall effect$ (3) $Coagulation$ (4) $Electrophoresis$ 89. $Aqueous solution of raw sugar when passed over beds of animal charcoal, it becomes colourless. Pick the correct set of terminologies that can be used for the above example. Adsorbent Adsorbate Process$ (1) $Solution of Sugar Animal Charcoal Sorption$ (2) $Animal Charcoal Solution of Sugar Absorption$ (3) $Animal Charcoal Colouring substance Adsorption$ (4) $Colouring Substance Animal Charcoal Adsorption$ 90. $Which can adsorb larger volume of hydrogen gas?$ (1) $Finely divided platinum$ (2) $Colloidal Fe (OH)_{3}$ (3) $Finely divided nickel$ (4) $Colloidal solution of palladium$