Surface Chemistry Class 12 MCQ for NEET

Surface Chemistry MCQ with Answers for NEET

Here are a few Surface Chemistry Class 12 MCQ for NEET Pdf. Let us practise or solve them to understand how much we really know about Surface Chemistry.

Important Points to Remember about Surface Chemistry

  1. Adsorption : The phenomenon of increase in concentration at the surface due to molecular surface force is known as adsorption. (ii) Adsorbate : The substances solids, gases or liquids which are adsorbed on the surface of adsorbent are called adsorbate. (iii) Adsorbent : The solid or liquid substance on the surface of which adsorption takes place is called adsorbent. Examples of adsorbents are activated charcoal, Pt, Pd, Ni, Silica gel, gelatin, Al2O3, starch. (iv) Absorption :When a substance is uniformly distributed throughout the body of a solid or liquid, the phenomenon is called absorption. (v) Sorption :It may be defined as the process in which both adsorption and absorption take place simultaneously.
  2. A colloidal system is made of two phases. The substance distributed as the colloidal particles is called Dispersed phase or internal phase or the discontinuous phase. The continuous phase in which the colloidal particles are dispersed is called dispersion medium.
  3. Emulsions are liquid-liquid colloidal system They are of two types : (i) Oil dispersed in water (O/W type), (ii) Water dispersed in oil (W/O type).
  4. Surfactants are those substances which are preferentially adsorbed at the interfaces like air-water, oil-water and solid-water interfaces. Thus, it is the surfactant which is responsible for micellisation and emulsification. Surfactants are divided into three categories: Cationic surfactants, Anionic Surfactants and Non Ionic Surfactants.

Read : MCQ on Environmental Chemistry 

Surface Chemistry MCQ Questions and Answers for class 12 Pdf  :

1. Catalytic poisons are___________

(1) Poison for catalyst

(2) Poison for reactant

(3) Poison for product

(4) None of these

Answer: 1

2. Which of the following is an example of emulsifying agent for w/o type emulsion__________

(1) Soap

(2) Heavy metal salts of fatty acid

(3) Starch

(4) Gum

Answer: 2

Read : MCQ on Adsorption 

3. A catalyst is more effective in___________

(1) Finely powdered state

(2) Colloidal state

(3) Rough surface

(4) All of these

Answer: 4

4. Zeolites are_________

(1) Water softener 

(2) Catalyst

(3) Both (1) and (2) 

(4) Colloids

Answer: 3

5. Which of the following process is used in the purification of colloidal solution_________

(1) Dialysis

(2) Coagulation

(3) Peptization

(4) Electrophoresis

Answer: 1

6. FeCl3 sol in hot water mixed with conc. NaOH is___________

(1) Positively charged colloid

(2) Negatively charged colloid

(3) Both (+) and (–) charge

(4) All of these

Answer : 2

7. The Langmuir adsorption isotherm is deduced using the assumption.

(1) The adsorption sites are equivalent in their ability to adsorb the particles.

(2) The heat of adsorption varies with coverage.

(3) The adsorption molecules interact with each other.

(4) The adsorption takes place in multilayers.

Answer: 1

8. Movement of disperssion medium in presence of electic field is known as_________

(1) Electro osmosis 

(2) Electro dialysis

(3) Electro dispersion 

(4) Electro phoresis

Answer: 1

9. Butter is an example of________

(1) Water oil emulsion

(2) Gas-liquid colloidal system

(3) Oil water emulsion

(4) Solid-solid colloidal system

Answer: 1

10. If x is amount of adsorbate and m is amount of adsorbent, which of the following relations is not related to adsorption process ?

(1) x/m = f(p) at constant T

(2) x/m = f(T) at constant p

(3) p = f(T) at constant (x/m)

(4) None of these 

Answer: 4

11. By which method we can convert ppt to colloidal solution__________

(1) Peptization

(2) Homogenisation

(3) Dispersion

(4) Solvation

Answer : 1

12. Which of the following is incorrect for physi-sorption_________

(1) Reversible

(2) Increases with increase in temperature

(3) Low heat of adsorption

(4) Increases with increase in surface area 

Answer : 2

13. In Freundlich Adsorption isotherm, the value of 1/n is____________

(1) 1 in case of physical adsorption

(2) 1 in case of chemisorption

(3) between 0 and 1 in all cases

(4) between 2 and 4 in all cases

Answer: 3

14. The nature of colloidal solution of methylene blue and haemoglobin is _____ and _____ respectively?

(1) positive, positive

(2) negative, negative

(3) positive, negative

(4) negative, positive

Answer: 1

15. Which of the following is correct example of sol and emulsion respectively?

(1) Paints, milk

(2) Ink, paints

(3) Fog, mist

(4) Smoke, colloidion

Answer: 1

16. Milk and cheese are respectively______

(1) solid sol and emulsion

(2) gel and emulsion

(3) solid sol and gel

(4) emulsion and gel

Answer: 4

17. Which of the following cannot be used to coagulate hydrophobic colloids______

(1) Persistent dialysis

(2) Electrophoresis

(3) On addition of oppositely charged electrolyte

(4) Dilution

Answer: 4

18. On which of the following properties does coagulating power of an ion depend ?

(1) The magnitude of the charge on the alone

(2) Size of the ion alone

(3) Both magnitude and sign of the charge the ion

(4) The sign of charge on the ion alone

Answer: 3

19. Which one of the following statements is  incorrect about enzyme catalysis?

(1) Enzymes are denaturated by ultraviolet rays and at high temperature

(2) Enzymes are least reactive at optimum temperature

(3) Enzymes are mostly proteinous in nature

(4) Enzyme action is specific

Answer: 2

20. The protecting power of lyophilic colloidal sol is expressed in terms of___________

(1) Critical miscelle concentration

(2) Oxidation number

(3) Coagulation value

(4) Gold numbe

Answer: 4

21. A colliodal solution is kept in dark and is illuminated by a beam of light then brightness appears at the right angle of direction of light. This effect is called_________

(1) Tyndall effect

(2) Brownian effect

(3) Hardy schulze effect

(4) None of these

Answer: 1

22. Hair cream is________

(1) Gel

(2) Emulsion

(3) Solid sol

(4) Sol

Answer: 2

23. According to Hardy Schulze law, the flocculating power of an ion increases with_____

(1) Decreases in size

(2) Increase in size

(3) Decrease in charge

(4) Increase in charge

Answer: 4

24. Which property of colloids is not dependent on the charge on colloidal particles ?

(1) Coagulation

(2) Electrophoresis

(3) Electro - osmosis

(4) Tyndall effect

Answer: 4

25. Which of the following forms cationic micelles above certain concentration_________

(1) Cetyltrimethylammonium bromide

(2) Sodium dodecyl sulphonate

(3) Sodium acetate

(4) Urea

Answer : 1

26. Which one of the following statements about the zeolites is false :

(1) Some of the SiO4– units are replaced by AlO5–and AlO9– ions in zeolites

(2) They are used as cation exchangers

(3) They have open structure which enables them to take up small molecules

(4) Zeolites are aluminosilicates having three dimensional network

Answer: 1

27. The correct statement in case of milk_______

(1) Milk is an emulsion of fat in water

(2) Milk in an emulsion of protein in water

(3) Milk is unstabilized by protein

(4) Milk is unstabilized by fat

Answer: 1

28. A colloidal system involves_______

(1) A state of dissolution

(2) A state of dispersion

(3) A state of suspension

(4) None

Answer: 2

29. In electrophoresis________

(1) Sol particles move towards opposite electrodes

(2) Medium moves towards opposite electrodes

(3) Neither (1) nor (2)

(4) Both (1) & (2)

Answer: 1

30. Detergent action of synthetic detergents is due to________

(1) Interfacial area

(2) High molecular weight

(3) Ionisation

(4) Emulsifying properties

Answer: 4

31. Which is not shown by sols_______

(1) Adsorption

(2) Tyndall effect

(3) Flocculation

(4) Paramagnetism

Answer: 4

32. Which of the following is an emulsifier ?

(1) Soap

(2) Water

(3) Oil

(4) NaCl

Answer: 1

33. Emulsifiers are generally___________

(1) Soaps

(2) Synthetic detergents

(3) Lyophilic sols

(4) All of the above

Answer: 4

34. In a reversible reaction a catalyst_________

(1) Increases the rate of forward reaction only

(2) Increases the rate of forward reaction to a greater extent than that of the backward reaction

(3) Increases the rate of forward reaction and decreases that of the backward reaction

(4) Increases the rate of forward and backward reaction equally

Answer : 4

35. Which is false for catalyst___________

(1) A catalyst can initiate a reaction

(2) It does not alter the position of equilibrium in a reversible reaction

(3) A catalyst remains unchanged in quantity and composition at the end of reaction

(4) Catalysts are sometimes very specific in respect of a reaction

Answer : 1

36. Physical adsorption is appreciable at________

(1) Higher temperature 

(2) Lower temperature

(3) At room temperature 

(4) 1000°C

Answer: 2

37. The rate of physical adsorption_________

(1) Decreases with increase of pressure

(2) Is independent at high pressure

(3) Is maximum at one atmospheric pressure

(4) Always increases with increase of pressure

Answer: 2

38. Which of the following is not a characteristic of chemi–sorption________

(1) Adsorption is irreversible

(2) DH is of the order of 40 kJ

(3) Adsorption is specific

(4) Adsorption increases with increase of surface area

Answer: 2

39. Which one of the following is not a correct statement ?

(1) Physical adsorption is reversible in nature

(2) Physical adsorption involves vander waals forces

(3) Rate of physical adsorption increases with increase of pressure on the adsorbate

(4) High activation energy is involved for physical adsorption

Answer: 4

40. The amount of gas adsorbed on charcoal increases with_________

(1) Temperature & pressure

(2) Temperature & decreases with pressure

(3) Pressure & decreases with temperature

(4) None

Answer: 3

41. Which characteristic of adsorption is wrong__________

(1) Physical adsorption in general decreases with temperature

(2) Physical adsorption in general increases with temperature

(3) Physical Adsorption is a reversible process

(4) Adsorption is limited to the surface only

Answer : 2

42. Hardy-Schulze rule states that___________

(1) Non-electrolytes have better coagulating action on colloids than electrolytes

(2) Sols are coagulated by effective ions whose charge is opposite to that of sol and the ions of higher charge are much more effective than the ions of lower charge

(3) Charge of the ions has no effect on the coagulation of a sol

(4) Sols are coagulated only by those ions whose charges is similar to that of the sol

Answer : 2