Students of class 12 Chemistry should refer to MCQ Questions Class 12 Chemistry Surface Chemistry with answers provided here which is an important chapter in Class 12 Chemistry NCERT textbook. These MCQ for Class 12 Chemistry with Answers have been prepared based on the latest CBSE and NCERT syllabus and examination guidelines for Class 12 Chemistry. The following MCQs can help you to practice and get better marks in the upcoming class 12 Chemistry examination

Chapter 5 Surface Chemistry MCQ with Answers Class 12 Chemistry

MCQ Questions Class 12 Chemistry Surface Chemistry provided below have been prepared by expert teachers of grade 12. These objective questions with solutions are expected to come in the upcoming Standard 12 examinations. Learn the below provided MCQ questions to get better marks in examinations.

Question. An aerosol is a :
(a) dispersion of a solid or liquid in a gas
(b) dispersion of a solid in a liquid
(c) dispersion of a liquid in a liquid
(d) solid solution

Question. An example of dispersion of a liquid in a gas is :
(a) milk
(b) vegetable oil
(c) foam
(d) mist

Question. Alloy is an example of
(a) gel
(b) solidified emulsion
(c) solid solution
(d) sol

Question. Which of the following is true about the value of refractive index of quartz glass?
(a) Same in all directions
(b) Different in different directions
(c) Cannot be measured
(d) Always zero

Question. Which of the following statement is not true about amorphous solids? 
(a) On heating they may become crystalline at certain temperature.
(b) They may become crystalline on keeping for long time.
(c) Amorphous solids can be moulded by heating.
(d) They are anisotropic in nature.

Question. Which is not correct regarding the physical adsorption of a gas on surface of solid ?
(a) On increasing temperature, adsorption increases continuously
(b) Enthalpy and entropy changes are negative
(c) Adsorption is more for some specific substance
(d) Reversible

Question. How many layers are adsorbed in chemical adsorption ?
(a) One
(b) Two
(c) Many
(d) Zero

Question. Adsorption due to strong chemical forces is called
(a) Chemisorption
(b) Physisorption
(c) Reversible adsorption
(d) Both (b) and (c)

Question. The sharp melting point of crystalline solids is due to ___________. 
(a) a regular arrangement of constituent particles observed over a short distance in the crystal lattice.
(b) a regular arrangement of constituent particles observed over a long distance in the crystal lattice.
(c) same arrangement of constituent particles in different directions.
(d) different arrangement of constituent particles in different directions.

Question. Which of the following conditions favours the existence of a substance in the solid state?
(a) High temperature
(b) Low temperature
(c) High thermal energy
(d) Weak cohesive forces

Question. Which of the following is not a characteristic of a crystalline solid?
(a) Definite and characteristic heat of fusion.
(b) Isotropic nature.
(c) A regular periodically repeated pattern of arrangement of constituent particles in the entire crystal.
(d) A true solid

Question. Which one of the following is a covalent crystal?
(a) Rock salt
(b) Ice
(c) Quartz
(d) Dry ice

Question. Identify the correct statement for the adsorption of a real gas on charcoal at 1 atm and l5°C. 
(a) Gases which are small in molecular size are adsorbed more
(b) Decrease in pressure increases the extent of adsorption
(c) Gases which are easily liquefiable are adsorbed more in quantity
(d) Gas which has a behaviour similar to an inert gas is adsorbed more 

Question. If (xi m) is the mass of adsorbate adsorbed per unit mass of adsorbent. p is the pressure of the adsorbate gas and a and b are constants, which of the following represents “Langmuir adso1ption isotherm” ?
(a) log (x/m)= log (a/b) + 1/a log p
(b) x/m = b/a + 1/ap
(c) x/m = 1+bp / ap
(d) 1 / (x/m)  = a/b + p/a
(e) 1 / (x/m) = a/b + 1/pa     

Question. Activated charcoal is used to remove colouring matter from pure substances. It works by 
(a) oxidation
(b) reduction
(c) bleaching
(d) adsorption         

Question. Which of the following is not correct ? 
(a) Enthalpy of physical adsorption is less compared to enthalpy of chemical adsorption
(b) Milk is an example of emulsion
(c) Physical adsorption increases with the increase in temperature
(d) Smoke is an aerosol   

Question. Which one of the following characteristics is not correct for physical adsorption ? 
(a) Adsorption on solids is reversible
(b) Adsorption increases with increase in temperature
(c) Adsorption is spontaneous
(d) Both enthalpy and entropy of adsorption are negative     

Question. The extent of adsorption of a gas on a solid depends on
(a) nature of the gas
(b) pressure of the gas
(c) temperature of the gas
(d) All of these     

Question. Which of the following is not a characteristic of chemiso1ption ?
(a) ΔH is the order of 400 kJ
(b) Adsorption is irreversible
(c) Adsorption may be multimolecular layer
(d) Adsorption is specific       

Question. In the case of autocatalysis
(a) product catalysis
(b) solvent catalysis
(c) reactant catalysis
(d) heat produced in the reaction catalysis       

Question. Which one of the following is an example of homogeneous catalysis?
(a) Haber’s process of synthesis of ammonia
(b) Catalytic conversion of sulphur dioxide to sulphur trioxide in the contact process
(c) Catalytic hydrogenation of oils
(d) Catalytic conversion of water gas to methanol
(e) Acid hydrolysis of methyl acetate     

Question. Hydrolysis ofurea is an example of
(a) homogeneous catalysis
(b) heterogeneous catalysis
(c) biochemical catalysis
(d) zeoIite catalysis     

Question. Which of the following solids is not an electrical conductor?
(i) Mg(s)
(ii) TiO(s)
(iii) I2(s)
(iv) H2O(s)
(a) (i) only
(b) (ii) only
(c) (iii) and (iv)
(d) (ii), (iii) and (iv)

Question. The number of atoms in a face centred cubic unit cell is
(a) 2
(b) 4
(c) 5
(d) 6

Question. In a face centred cubic lattice, atom A occupies the corner positions and atom B occupies the face centre positions. If one atom of B is missing from one of the face centred points, the formula of the compound is:
(a) AB2
(b) A2B3
(c) A2B5
(d) A2B

Question. The total number of tetrahedral voids in the face centred unit cell is __________.
(a) 6
(b) 8
(c) 10
(d) 12

Question. If Z is the number of atoms in the unit cell that represents the closest packing sequence—ABC ABC, the number of tetrahedral voids in the unit cell is equal to
(a) Z
(b) 2Z
(c) Z/2
(d) Z/4

Question. In which pair most efficient packing is present?
(a) hcp and bcc
(b) hcp and ccp
(c) bcc and ccp
(d) bcc and simple cubic cell

Question. The role of a catalyst in a reversible reaction is to
(a) increase the rate of forward reaction
(b) decrease the rate of backward reaction
(c) alter the equilibrium constant of the reaction
(d) allow the equilibrium to be achieved quickly

Question. Catalytic poisons act by :
(a) making the products chemically inactive.
(b) increasing the rate of the backward reaction.
(c) chemical combination with any one of the reactants.
(d) preferential adsorption on the catalyst surface.

Question. Which one of the following is an example of homogeneous catalysis ?
(a) Haber’s process of synthesis of ammonia
(b) Catalytic conversion of SO2 to SO3 in contact process
(c) Catalytic hydrogenation of oils
(d) Acid hydrolysis of methyl acetate.

Question. A solid compound XY has NaCl structure. If the radius of the cation is 100 pm, the radius of the anion (Y–) will be
(a) 275.1 pm
(b) 322.5 pm
(c) 241.5 pm
(d) 165.7 pm

Question. Adsorbed acetic acid on activated charcoal is:
(a) adsorber
(b) absorber
(c) adsorbent
(d) adsorbate

Question. Adsorption is always
(a) endothermic
(b) exothermic
(c) exothermic in case of physical and endothermic in case of chemical
(d) Either (a) or (b)

Question. A catalyst :
(a) lowers the activation energy
(b) changes the rate constant
(c) changes the product
(d) itself destroyed in the reaction

Question. Active charcoal is a good catalyst because it
(a) is made up of carbon atoms.
(b) is very reactive.
(c) has more adsorption power.
(d) has inert nature toward reagents.

Question. Choose the incorrect statement in respect of physisorption?
(a) It is not specific in nature
(b) It arises because of van der Waal’s force
(c) It is reversible in nature
(d) Enthalpy of adsorption is in the range 80-240 kJ mol–1

Question. The term ‘sorption’ stands for ___________.
(a) absorption
(b) adsorption
(c) both absorption and adsorption
(d) desorption

Question. Which of the following kind of catalysis can be explained by the adsorption theory ?
(a) Homogeneous catalysis
(b) Acid – base catalysis
(c) Heterogeneous catalysis
(d) Enzyme catalysis

Question. Catalyst increases the rate of reaction by
(a) decreasing threshold energy
(b) decreasing activation energy
(c) increasing activation energy
(d) decreasing equilibrium constant

Question. A catalyst can affect reversible reaction by
(a) changing equilibrium constant
(b) slowing forward reaction
(c) attaining equilibria in both directions
(d) None of these

Question. In physical adsorption, gas molecules are bound on the solid surface by
(a) chemical forces
(b) electrostatic forces
(c) gravitational forces
(d) van der Waal’s forces

Question. Which of the following statements is not correct ?
(a) Physical adsorption is due to van der Waal’s forces
(b) Chemical adsorption first decreases with increase in temperature.
(c) Physical adsorption is reversible
(d) Adsorption energy for a chemical adsorption is generally greater than that of physical adsorption.

Question. AB crystallizes in a body centred cubic lattice with edge length ‘a’ equal to 387 pm. The distance between two oppositely charged ions in the lattice is
(a) 250 pm
(b) 200 pm
(c) 300 pm
(d) 335 pm

Question. Adsorption is accompanied by
(a) decrease in enthalpy and increase in entropy
(b) increase in enthalpy and increase in entropy
(c) decrease in enthalpy and decrease in entropy
(d) increase in enthalpy and decrease in entropy

Question. Identify the correct statement regarding enzymes
(a) Enzymes are specific biological catalysts that cannot be poisoned.
(b) Enzymes are normally heterogeneous catalysts that are very specific in their action.
(c) Enzymes are specific biological catalysts that can normally function at very high temperatures (T 􀁼 1000K).
(d) Enzymes are specific biological catalysts that possess well-defined active sites.

Question. A biological catalyst is
(a) an enzyme
(b) a carbohydrate
(c) an amino acid
(d) a nitrogenous base

Question. The fraction of the total volume occupied by the atoms present in a simple cube is
(a) π/4
(b) π/6
(c) π/(3√2)
(d) π/(4√2)

Question. A metallic crystal has the bcc type staking pattern. What percentage of volume of this lattice is empty space?
(a) 68%
(b) 32%
(c) 26%
(d) 74%

Question. Extent of physisorption of a gas increases with _______.
(a) increase in temperature.
(b) decrease in temperature.
(c) decrease in surface area of adsorbent.
(d) decrease in strength of van der Waal’s forces.

Question. Which of the following crystals does not exhibit Frenkel defect?
(a) AgBr
(b) AgCl
(c) KBr
(d) ZnS

Question. The action of enzymes in living system is to :
(a) supply energy to tissues
(b) enhance immunity
(c) circulate oxygen
(d) enhance the rate of biochemical reactions.

Question. Hydrolysis of urea is an example of
(a) homogenous catalysis
(b) heterogenous catalysis
(c) biochemical catalysis
(d) zeolite catalysis

Question. Which of the following is true about the charge acquired by p-type semiconductors?
(a) Positive
(b) Neutral
(c) Negative
(d) Depends on concentration of p impurity

Question. The efficiency of an enzyme in catalysing a reaction is due to its capacity
(a) to form a strong enzyme-substrate complex
(b) to decrease the bond energies of substrate molecule
(c) to change the shape of the substrate molecule
(d) to lower the activation energy of the reaction

Question. The size of colloidal particles is between
(a) 10–7 – 10–9 cm
(b) 10–9 – 10–11 cm
(c) 10–5 – 10–7 cm
(d) 10–2 – 10–3 cm

Question. Which of the following is not a favourable condition for physical adsorption ?
(a) High pressure
(b) Negative 􀀧H
(c) Higher critical temperature of adsorbate
(d) High temperature

Question. Physical adsorption of a gaseous species may change to chemical adsorption with ________.
(a) decrease in temperature
(b) increase in temperature
(c) increase in surface area of adsorbent
(d) decrease in surface area of adsorbent

Question. Adsorption of gases on solid surface is exothermic reaction because
(a) free energy increases
(b) enthalpy is positive
(c) entropy increases
(d) enthalpy is negative

Question. The gas which is least adsorbed on charcoal (under identical conditions) is
(a) HCl
(b) O2
(c) CO2
(d) NH3

Question. Extent of adsorption of adsorbate from solution phase increases with _________.
(a) increase in amount of adsorbate in solution.
(b) decrease in surface area of adsorbent.
(c) increase in temperature of solution.
(d) decrease in amount of adsorbate in solution.

We hope the above multiple choice questions for Class 12 Chemistry for Chapter 5 Surface Chemistry provided above with answers based on the latest syllabus and examination guidelines issued by CBSE, NCERT and KVS are really useful for you. Surface Chemistry is an important chapter in Class 12 as it provides very strong understanding about this topic. Students should go through the answers provided for the MCQs after they have themselves solved the questions. All MCQs have been provided with four options for the students to solve. These questions are really useful for benefit of class 12 students. Please go through these and let us know if you have any feedback in the comments section.