MCQ Questions Chapter 5 Surface Chemistry Class 12 Chemistry

Please refer to MCQ Questions Chapter 5 Surface Chemistry Class 12 Chemistry with answers provided below. These multiple-choice questions have been developed based on the latest NCERT book for class 12 Chemistry issued for the current academic year. We have provided MCQ Questions for Class 12 Chemistry for all chapters on our website. Students should learn the objective based questions for Chapter 5 Surface Chemistry in Class 12 Chemistry provided below to get more marks in exams.

Chapter 5 Surface Chemistry MCQ Questions

Please refer to the following Chapter 5 Surface Chemistry MCQ Questions Class 12 Chemistry with solutions for all important topics in the chapter.

MCQ Questions Answers for Chapter 5 Surface Chemistry Class 12 Chemistry

Question. Which type of molecules form micelles?
(a) Non-polar molecules
(b) Polar molecules
(c) Surfactant molecules
(d) Salt of weak acid and weak base     

Question. In multimolecular colloidal sols, atoms or molecules are held together by
(a) H-bonding
(b) van der Waals’ forces
(c) ionic bonding
(d) polar covalent bonding       

Question. Smoke is an example of
(a) solid dispersed in solid
(b) gas dispersed in liquid
(c) solid dispersed in gas
(d) gas dispersed in solid     

Question. A gel is
(a) a liquid mass of a lyophilic sol in which all the dispersion medium has penetrated into the sol particles
(b) like an emulsion which is stabilised by adding emulsifying agent
(c) a semirigid mass of a lyophobic sol in which all the dispersion medium has penetrated into the sol particles
(d) a semirigid mass of a lyophilic sol in which the dispersion medium has penetrated into the sol particles   

Question. Which one of the following is correctly matched?
(a) Emulsion – smoke
(b) Gel – butter
(c) Aerosol – hair cream
(d) Sol – whipped cream     

Question. Lyophilic sols are
(a) irreversible sols
(b) prepared from inorganic compounds
(c) coagulated by adding electrolytes
(d) self-stabilising   

Question. The disperse phase, dispersion medium and nature of colloidal solution (lyophilic or lyophobic) of ‘gold sol’ respectively are
(a) solid, solid, lyophobic
(b) liquid, liquid, lyophobic
(c) solid, liquid, lyophobic
(d) solid, liquid, lyophilic     

Question. Which of the following has maximum coagulation power with ferric hydroxide sol?
(a) Cryolite
(b) K₂C₂O₄
(c) K₃[Fe(CN)₆] 
(d) K [Fe(CN) ]   

Question. Which of the following is not the property of hydrophilic solutions?
(a) High concentration of dispersed phase can be easily obtained
(b) Coagulation is reversible
(c) Viscosity and surface tension are nearly the same as that of water
(d) The charge of the particles depend on the pH of the medium and it may be positive, negative or zero     

Question. The critical micelle concentration (CMC) is
(a) the concentration at which micellisation starts
(b) the concentration at which the true solution is formed
(c) the concentration at which one molar electrolyte is present per 1000 g of the solution
(d) the concentration at which ΔH = 0       

Question. Micelles form only
(a) below the critical micelle concentration (CMC) and below the Kraft temperature (T_k )
(b) above CMC and below the T_k
(c) above the CMC and above the T_k
(d) below the CMC and above the T_k       

Question. Peptisation involves
(a) precipitation of colloidal particles
(b) disintegration of colloidal aggregates
(c) evaporation of dispersion medium
(d) impact of molecules of the dispersion medium on the colloidal particles     

Question. Fog is a colloidal solution of
(a) liquid particles dispersed in a gas
(b) gaseous particles dispersed in a liquid
(c) solid particles dispersed in a liquid
(d) solid particles dispersed in a gas     

Question. During the micelle formation,
(a) ΔH = +ve, ΔS = +ve
(b) ΔH = −ve, ΔS = −ve
(c) ΔH = −ve, ΔS = + ve
(d) ΔH = +ve, ΔS = −ve     

Question. A particle of radius 1 cm is broken to form colloidal particles of radius1000 Å. The number of colloidal particles produced are
(a) 10¹⁵
(b) 6.023 × 10²³  
(c) 10¹²
(d) 10¹⁰     

Question. What is the value of 1/ n in Freundlich adsorption isotherm?
(a) Between 2 and 4 in all cases 
(b) Between 0 and 1 in all cases
(c) 1 in case of chemisorption
(d) 1 in case of physical adsorption       

Question. Which of the following statements is incorrect regarding physisorption? 
(a) It occurs because of van der Waals’ forces
(b) More easily liquefiable gases are adsorbed readily
(c) Under high pressure it results into multin1olecular layer on adsorbent surface
(d) Enthalpy of adsorption (ΔH_adsorption) is slow and positive     

Question. Rate of physical adsorption increases with 
(a) decrease in surface area
(b) decrease in temperature
(c) decrease in pressure
(d) increase in temperature     

Question. From the following which is not a surface phenomenon?
(a) Corrosion 
(b) Crystallisation
(c) Heterogeneous catalysis
(d) Water and its vapour in a dossed vessel
(e) None of the above     

Question. Freundlich equation for adsorption of gases (in amount of xg) on a solid (in amount of mg) at constant temperature can be expressed as
(a) log x/m = log p + 1/n log k
(b) log x/m = log k + 1/n log p
(c) x/m ∝ pⁿ
(d) x/m = log p + 1/n log k       

Question. Which one of the following graphs represents Freundlich adsorption isothenn ?   

Question. Freundlich adsorption isothenn is 
(a) x / m = kp^1/n
(b) x = mkp^1/n
(c) x / m = kp^-n
(d) All of these     

Question. Plot oflog xi magainst log pis a straight line inclined at an angle of 45°. When the pressure is 0.5 atm and Freundlich parameter, k is 10, the amount of solute adsorbed per gram of adsorbent will be (Jog 5 = 0. 6990) 
(a) 1 g
(b) 2 g
(c) 3 g
(d) 5g
(e) 2.5g     

Question. Which of the following is a wrong statement for physisorption? 
(a) It is a reversible reaction
(b) Reaction requires an energy of activation
(c) The value of adsorption enthalpy is low
(d) It generally occurs at a low temperature     

Question. Which among the following statements are correct with respect to adsorption of gases on a solid?
I. The extent of adsorption is equal to kpⁿ according to Freundlich isotherm.
II. The extent of adsorption is equal to kp^1/n ” according to Freundlich isotherm.
III. The extent of adsorption is equal to (1 + bp) / apaccording to Langmir isotherm.
IV. The extent of adsorption is equal to ap / (1 + bp) according to Langmir isotherm.
V. Freundlich adsorption isotherm fails at low pressure, where k, a and b are constants and p is pressure.
(a) I and III
(c) II and III
(b) I and IV
(d) II and IV     

Question. The colloidal sol formed from SnO₂ in acidic and basic medium respectively are
(a) [SnO₂]SnO₃²⁻ : 2 Na⁺ and [SnO₂]Sn⁴⁺ : 4Cl⁻
(b) [SnO₂]Sn⁴⁺ and [SnO₂]SnO₃²⁻ : 2 Na⁺
(c) positively and negatively charged
(d) [SnO2]SnO₃²⁻ : 2Na²⁺ in both the media       

Question. Addition of lyophilic solution to the emulsion, forms
(a) a protective film around the dispersed phase
(b) a protective film around the dispersion medium
(c) an aerosol
(d) true solution       

Question. Lyophilic solutions are more stable than lyophobic solutions because
(a) the colloidal particles have positive charge
(b) the colloidal particles have negative charge
(c) the colloidal particles are solvated
(d) there is strong electrostatic repulsions between the negatively charged colloidal particles         

Question.  Separation of colloidal particles from those of molecular dimensions by means of electric current is known as
(a) electroosmosis
(b) electrophoresis
(c) electrodialysis
(d) electrolysis       

Question. The Brownian movement is due to
(a) enthalpy change during the formation of colloids
(b) attractive force between the colloidal particles and the molecules of dispersion medium
(c) the impact of molecules of the dispersion medium on the colloidal particles
(d) the movement of positively charged colloidal particles to negatively charged particle       

Question. Among the following, the surfactant that will form micelles in aqueous solution at the lowest molar concentration at ambient conditions, is
(a) CH₃(CH₂)₁₅N⁺(CH₃)₃Br⁻
(b) CH₃(CH₂)₁₁OSO⁻₃Na⁺
(c) CH₃(CH₂)₆COO⁻Na⁺ 
(d) CH₃(CH₂)₁₁N⁺(CH₃)₃Br⁻     

Question. Which of the following will show Tyndall effect?
(a) Aqueous solution of soap below critical micelle concentration
(b) Aqueous solution of soap above critical micelle concentration
(c) Aqueous solution of sodium chloride
(d) Aqueous solution of sugar     

Question. Gold number is the index for
(a) protective power of lyophilic colloid
(b) purity of gold
(c) metallic gold
(d) electroplated gold     

Question. A freshly prepared Fe(OH)₃ precipitate is peptised by adding FeCl₃ solution. The charge on the colloidal particles is due to preferential adsorption of
(a) Br⁻ ion
(b) Fe³⁺ion 
(c)OH⁻ ion
(d) Ba²⁺ ion         

Question. Which of the following statements is correct for Tyndall effect?
(a) Scattering and polarising of light by small suspended particles is called Tyndall effect
(b) Tyndall effect of colloidal particles is due to dispersion of light
(c) Tyndall effect is due to refraction of light
(d) zig-zag motion of suspended particles     

Question. The values of colligative properties of colloidal solution are of small order in comparison to those shown by true solutions of same concentration because colloidal particles
(a) exhibit enormous surface area
(b) remain suspended in the dispersion medium
(c) form lyophilic colloids
(d) are comparatively less in number     

Question. In a coagulating experiment, 5 mL of As₂S₃ is mixed with distilled water and 0.2 M solution of an electrolyte AB, so that the total volume is 20 mL. All solutions containing 5.4 mL of AB coagulate within 2 min. The flocculation value of AB (in millimole) is
(a) 5
(b) 50
(c) 54
(d) None of these       

Question. Potassium stearate is obtained by the saponification of an oil or fat. It has formula CH₃—(CH₂)₁₆— COOK. The molecule has a lyophobic terminal CH₃ and a lyophilic terminal—COOK. Potassium stearate is an example of
(a) lyophilic colloid
(b) lyophobic colloid
(c) macromolecular colloid
(d) micelle or associated colloid       

Question. The coagulating power of electrolytes having ions Na⁺ ,Al³⁺ and Ba²⁺ for arsenic sulphide solution increases in the order 
(a) Na⁺ < Ba²⁺ < Al³⁺
(b) Ba²⁺ < Na⁺ Al³⁺
(c) Al³⁺ < Na⁺ < Ba²⁺
(d) Al³⁺ < Ba²⁺ < Na⁺       

Question. Which of the following process is responsible for the formation of delta at a place where rivers meet the sea?
(a) Emulsification
(b) Colloidal formation
(c) Coagulation
(d) Peptisation     

Question. Which of the following ions have minimum value of flocculating power?
(a) PO₄³⁻
(b) SO₄²−
(c) SO₃²⁻
(d) NO₃⁻     

Question. 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
(a) D < A < C < B
(b) C < B < D < A
(c) A < C < B < D
(d) B < D < A < C       

Question. Hardy-Schulze law states that
(a) larger the charge on the coagulating ions, greater is its coagulating power, having opposite sign of solution
(b) solution must have zero gold number
(c) dispersed phase and dispersion medium must be of the same sign
(d) micelles coagulate in the presence of surfactants   

Question. The migration of dispersion medium under the influence of an electric potential is called j
(a) cataphoresis
(b) electroosmosis
(c) electrophoresis
(d) gas dispersed in solid     

Question. Which of the following statements is incorrect?
(a) Emulsions are prepared by shaking two liquid components, say oil and water and adding some emulsifying agent
(b) Water in oil emulsions are formed when the emulsifying agent at the interface is chiefly in the water phase
(c) Water in oil emulsions are formed when the emulsifying agent at the interface is chiefly in the oil phase
(d) Gems and gels mixed together to give emulsions       

Question. When 9.0 mL of arsenious sulphide sol and 1.0 mL of 0.1 M BaCl₂ are mixed, turbidity due to precipitation just appears after 2 h. The effective ion and its coagulation value respectively are
(a) Cl⁻, 10 millimol L ⁻¹
(b) Cl⁻, 20 millimol L ⁻¹
(c) Ba²⁺, 10 millimol L ⁻¹
(d) Ba²⁺, 20  millimol L ⁻¹       

Question. The dispersed phase in colloidal iron (III) hydroxide and colloidal gold is positively and negatively charged, respectively. Which of the following statements is not correct?
(a) Coagulation in both sols can be brought about by electrophoresis
(b) Mixing the sols has no effect
(c) Sodium sulphate solution causes coagulation in both sols
(d) Magnesium chloride solution coagulates the gold sol more readily than the iron (III) hydroxide sol   

Question. Which one of the following does not involve coagulation?
(a) Clotting of blood by the use of ferric chloride
(b) Formation of delta region
(c) Treatment of drinking water by potash alum
(d) Peptisation   

Question. When dilute aqueous solution of AgNO₃ (excess) is added to KI solution, positively charged sol particles of AgI are formed due to adsorption of ion
(a) K⁺
(b) Ag⁺
(c) I⁻
(d) NO₃⁻       

Question. The coagulation values of AlCl3 and NaCl are 0.093 and 52 respectively. The ratio of coagulating powers of both will be
(a) 0.093 : 1
(b) 52 : 1
(c) 559 : 1
(d) 1.788 : 1         

Question. When 6.0 × 10⁻⁵ g of a protective colloid was added to 20 mL of a standard gold sol, the precipitation of latter was just prevented on addition of 1 mL of 10% NaCl solution. The gold number of the protective colloid is
(a) 3
(b) 3 × 10⁻⁵
(c) 0.06
(d) 0.03   

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