Surface Chemistry PYQs Set 7 (PDF)

Set 7 of 9 · Questions 181-210 of 248

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Mere Teacher · Previous Year Questions JEE Main Chemistry · Surface Chemistry · Set 7 (Q181-210)
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181. $Match List - I with List - II. List -I (Colloid Preparation Method) (A) Hydrolysis (B) Reduction (C) Oxidation (D) Double Decomposition List -II (Chemical Reaction) (I) 2 AuCl_{3} + 3 HCHO + 3 H_{2} O ⟶ 2 Au (sol) + 3 HCOOH + 6 HCl (II) As_{2} O_{3} + 3 H_{2} S \to As_{2} S_{3} (sol) + 3 H_{2} O (III) SO_{2} + 2 H_{2} S \to 3 S (sol) + 2 H_{2} O (IV) FeCl_{3} + 3 H_{2} O \to Fe (OH)_{3} (sol) + 3 HCl Choose the most appropriate answer from the options given below.$ (1) $(A)-(i), (B)-(iii), (C)-(ii), (D)-(iv)$ (2) $(A)-(iv), (B)-(i), (C)-(iii), (D)-(ii)$ (3) $(A)-(iv), (B)-(ii), (C)-(iii), (D)-(i)$ (4) $(A)-(i), (B)-(ii), (C)-(iv), (D)-(iii)$ 182. $The colour of sky is due to$ (1) $absorption of light by atmospheric gases$ (2) $transmission of light$ (3) $wavelength of scattered light$ (4) $all of these.$ 183. $Catalysts in following reactions are (I) CH_{3} COOCH_{3} (l) + H_{2} O (l) \to CH_{3} COOH (aq) + CH_{3} OH (l) (II) 2 SO_{2} (g) \to 2 SO_{3} (g) (III) 2 SO_{2} (g) + O_{2} (g) \to 2 SO_{3} (g) (IV) N_{2} (g) + 3 H_{2} (g) \to 2 NH_{3} (g)$ (1) $HCl (l), Pt (s), NO (g) and Fe (s)$ (2) $HCl (l), NO (g), Pt (s) and Fe (s)$ (3) $HCl (l), Ni (s), NO (g) and Fe(s)$ (4) $HCl (l), Pt (s), N_{2} O (g) and Fe(s)$ 184. $Zeta potential is$ (1) $potential required to bring about coagulation of a colloidal sol$ (2) $potential required to give the particle a speed of 1 cm s^{- 1}$ (3) $potential difference between fixed charged layer and the diffused layer having opposite charges$ (4) $potential energy of the colloidal particles.$ 185. $The conditions given below are in the context of observing Tyndall effect in colloidal solutions:(A) The diameter of the colloidal particles is comparable to the wavelength of light used.(B) The diameter of the colloidal particles is much smaller than the wavelength of light used.(C) The diameter of the colloidal particles is much larger than the wavelength of light used.(D) The refractive indices of the dispersed phase and the dispersion medium are comparable.(E) The dispersed phase has a very different refractive index from the dispersion medium. Choose the most appropriate conditions from the options given below:$ (1) $(A) and (E) only$ (2) $(C) and (D) only$ (3) $(A) and (D) only$ (4) $(B) and (E) only$ 186. $Fog is a colloidal solution of$ (1) $solid in gas$ (2) $gas in gas$ (3) $liquid in gas$ (4) $gas in liquid.$ 187. $Peptization is a:$ (1) $process of bringing colloidal molecule into solution$ (2) $process of converting precipitate into colloidal solution$ (3) $process of converting a colloidal solution into precipitate$ (4) $process of converting soluble particles to form colloidal solution.$ 188. $An example for autocatalysis is$ (1) $oxidation of NO to NO_{2}$ (2) $oxidation of SO_{2} to SO_{3}$ (3) $decomposition of KClO_{3} to KCl and O_{2}$ (4) $oxidation of oxalic acid by acidified KMnO_{4} .$ 189. $Rate of physisorption increases with$ (1) $decrease in temperature$ (2) $increase in temperature$ (3) $decrease in pressure$ (4) $decrease in surface area$ 190. $Gold sol is not$ (1) $a macromolecular colloid$ (2) $a lyophobic colloid$ (3) $a multimolecular colloid$ (4) $negatively charged colloid.$ 191. $Tyndall effect is observed when$ (1) $The diameter of dispersed particles is much larger than the wavelength of light used.$ (2) $The diameter of dispersed particles is similar to the wavelength of light used.$ (3) $The diameter of dispersed particles is much smaller than the wavelength of light used.$ (4) $The refractive index of dispersed phase is greater than that of the dispersion medium.$ 192. $Lyophilic sols are$ (1) $Irreversible sols$ (2) $They are prepared from inorganic compound$ (3) $Coagulated by adding electrolytes$ (4) $Self-stabilizing$ 193. $Match the following: (I) Foam (A) Smoke (II) Gel (B) cell fluid (III) Aerosol (C) jellies (IV) Emulsion (D) rubber (E) froth (F) Milk$ (1) $(I)-(E), (II)-(C), (III)-(A), (IV)-(F)$ (2) $(I)-(B), (II)-(C), (III)-(E), (IV)-(D)$ (3) $(I)-(D), (II)-(B), (III)-(A), (IV)-(E)$ (4) $(I)-(D), (II)-(B), (III)-(E), (IV)-(F)$ 194. $Which of the following is used for the preparation of colloids?$ (1) $Van Arkel Method$ (2) $Bredig's Arc Method$ (3) $Mond Process$ (4) $Ostwald Process$ 195. $Under ambient conditions, which among the following surfactants will form micelles in aqueous solution at lowest molar concentration?$ (1) $CH3-(CH2)8 -COO- Na+$ (2) $CH3(CH2)11 N \oplus (CH3)3Br-$ (3) $CH3-(CH2)13-OSO3- Na+$ (4) $CH3(CH2)15 N \oplus (CH3)3Br-$ 196. $The most appropriate method of making egg-albumin sol is$ (1) $Keep the egg in boiling water for 10 minutes. After removing the shell, transfer the yellow part of the content to 100 mL of 5% w/V saline solution and homogenize with a mechanical shaker.$ (2) $Break an egg carefully and transfer the transparent part of the content to 100 mL of 5% w/V saline solution and stir well.$ (3) $Keep the egg in boiling water for 10 minutes. After removing the shell, transfer the white part of the content to 100 mL of 5% w/V saline solution and homogenize with a mechanical shaker.$ (4) $Break an egg carefully and transfer only the yellow part of the content to 100 mL of 5% w/V saline solution and stir well.$ 197. $Among the following, the false statement is:$ (1) $It is possible to cause artificial rain by throwing electrified sand carrying charge opposite to the one on clouds from an aeroplane.$ (2) $Tyndall effect can be used to distinguish between a colloidal solution and a true solution.$ (3) $Lyophilic sol can be coagulated by adding an electrolyte.$ (4) $Latex is a colloidal solution of rubber particles which are positively charged.$ 198. $In langmuir’s model of adsorption of a gas on a solid surface:$ (1) $the rate of dissociation of adsorbed molecules from the surface does not depend on the surface covered$ (2) $the adsorption at a single site on the surface may involve multiple molecules at the same time$ (3) $the mass of gas striking a given area of surface is proportional to the pressure of the gas$ (4) $the mass of gas striking a given area of surface is independent of the pressure of the gas$ 199. $Milk-water mixture when viewed by the reflected light appears in which colour?$ (1) $Yellow$ (2) $Green$ (3) $Blue$ (4) $Red$ 200. $Dalda is prepared from oils by$ (1) $hydrolysis$ (2) $distillation$ (3) $oxidation$ (4) $reduction.$ 201. $Which of the following statements is incorrect w.r.t. physisorption?$ (1) $The forces involved are van der Waals' forces.$ (2) $More easily liquifiable gases are adsorbed easily.$ (3) $Under high pressure it results into multi-molecular layer on adsorbent surface.$ (4) $Δ H_{adsorption} is low and +ve.$ 202. $A sample of red ink (a colloidal suspension) is prepared by mixing eosin dye, egg white, HCHO and water. The component which ensures stability of the ink sample is:$ (1) $HCHO$ (2) $Water$ (3) $Eosin dye$ (4) $Egg white$ 203. $Gold numbers of some colloids are: Gelatin: 0.005 - 0.01, Gum Arabic: 0.15 - 0.25 ; Oleate: 0.04 - 1.0; Starch : 15 - 25. Which among these is a better protective colloid?$ (1) $Gelatin$ (2) $Starch$ (3) $Gum Arabic$ (4) $Oleate$ 204. $Gold numbers of protective colloids A, B, C and D are 0.50, 0.01, 0.10 and 0.005, respectively. The correct order of their protective powers is$ (1) $C < B < D < A$ (2) $A < C < B < D$ (3) $B < D < A < C$ (4) $D < A < C < B$ 205. $Among the colloids cheese (c), milk (M) and smoke (S), the correct combination of the dispered phase and dispersion medium, respectively is :$ (1) $C : liquid in solid; M : liquid in liquid; S : solid in gas$ (2) $C : solid in liquid; M : liquid in liquid; S : gas in solid$ (3) $C : solid in liquid; M : solid in liquid; S : solid in gas$ (4) $C : liquid in solid; M : liquid in solid; S : solid in gas$ 206. $The disperse phase in colloidal iron (III) hydroxide and colloidal gold is positively and negatively charged, respectively. Which of the following statements is NOT correct?$ (1) $Coagulation in both sols can be brought about by electrophoresis$ (2) $Mixing the sols has no effect$ (3) $Sodium sulphate solution causes coagulation in both sols$ (4) $Magnesium chloride solution coagulates, the gold sol more readily than the iron (III) hydroxide sol.$ 207. $Tyndall effect is more effectively shown by:$ (1) $true solution$ (2) $lyophilic colloid$ (3) $lyophobic colloid$ (4) $suspension$ 208. $Which one of the following is not a property of physical adsorption?$ (1) $Higher the pressure, more the adsorption$ (2) $Greater the surface area, more the adsorption$ (3) $Lower the temperature, more the adsorption$ (4) $Unilayer adsorption occurs$ 209. $Photographic plates are prepared by coating emulsion of which of the following in gelatin.$ (1) $AgBr$ (2) $CuBr$ (3) $ZnB_{2}$ (4) $FeBr_{2}$ 210. $The number of correct statements about modern adsorption theory of heterogeneous catalysis from the following is . (A) The catalyst is diffused over the surface of reactants. (B) Reactants are adsorbed on the surface of the catalyst. (C) Occurrence of chemical reaction on the catalyst's surface through formation of an intermediate. (D) It is a combination of intermediate compound formation theory and the old adsorption theory. (E) It explains the action of the catalyst as well as those of catalytic promoters and poisons.$