Adsorption is multilayer in the case of

• physical adsorption

• chemisorption

• Both (a) and (b)

• None of the above

72.

Which of the following is not a method of preparation of colloidal solution?

• Electrical dispersion

• Peptization

• Coagulation

• Mechanical dispersion

Consider the following statements. The role of catalyst is to

(1) reduce the activation energy

(2) increase the activation energy

(3) increase the rate of attainment of equilibrium

(4) decrease the rate of attainment of equilibrium

Which ofthe statements given above are correct?

• (2) and (4)

• (1) and (4)

• (1) and (3)

• (2) and (3)

Finely divided powder of charcoal adsorbs the substance X to a large extent. This is because

• the surface area of charcoal is increased

• charcoal powder can be spread over X homogeneously

• X can be spread over charcoal homogeneously

• charcoal is highly reactive

Which one of the following has minimum gold number?

• Starch

• Sodium oleate

• Gelatin

• Gum arabic

Syneresis is a process in which

• spontaneous outcome of internal liquid without disturbing gel structure takes place

• sol particles absorb light

• aggregation of molecules to form micelle

• separation of soluble impurities from sols take place

The simplest way to check whether a system is colloidal is by

• electrodialysis

• finding out particle size

• Tyndall effect

• Brownian movement

Which statement is true?

• The adsorption of H₂ by platinum black is known as sorption

• The adsorption of H₂ by charcoal is known as occlusion

• The adsorption of H₂ by platinum black is known as occlusion

• The absorption of H₂ by charcoal is known as chemisorption.

In the case of auto catalysis

• product catalysis

• solvent catalysis

• reactant catalysis

• heat produced in the reaction catalysis

Which among the following statements is false?

• The adsorption may be monolayered or multilayered

• Particle size of adsorbent will not affect the amount of adsorption

• Increase of pressure increases amount of adsorption

• Increase of temperature may decrease the amount of adsorption