Write any two characteristics of Chemisorption.

Why does physisorption decrease with the increase of temperature?

Why are powdered substances more effective adsorbents than their crystalline forms?

Why is it necessary to remove CO when ammonia is obtained by Haber’s process?

Why is the ester hydrolysis slow in the beginning and becomes faster after sometime?

What is the role of desorption in the process of catalysis?

What modification can you suggest in the Hardy-Schulze law?

Why is it essential to wash the precipitate with water before estimating it quantitatively?

Distinguish between the meaning of the terms adsorption and absorption. Give one example of each.

What is the difference between physisorption and chemisorption?

Give reason why a finely divided substance is more effective as an adsorbent.

What are the factors which influence the adsorption of a gas on a solid?

What is an adsorption isotherm? Describe Freundlich adsorption isotherm.

What do you understand by activation of adsorbent? How is it achieved?

What role does adsorption play in heterogeneous catalysis?

Why is adsorption always exothermic?

How are the colloidal solutions classified on the basis of physical states of the dispersed phase and dispersion medium?

Discuss the effect of pressure and temperature on the adsorption of gases on solids.

What are lyophilic and lyophobic sols? Give one example of each type. Why are hydrophobic sols easily coagulated?

What is the difference between multimolecular and macromolecular colloids? Give one example of each. How are associated colloids different from these two types of colloids?

What are enzymes? Write in brief the mechanism of enzyme catalysis.

How are colloids classified on the basis of (I) Physical states ofcomponents (II) Nature of dispersion mediumand (III) Interaction between dispersed phase and dispersion medium?

Explain what is observed (I) When a beam of light is passed through a colloidalsol. (II) An electrolyte, NaCl is added to hydrated ferric oxidesol. (III) Electric current is passed through a colloidal sol?

What are emulsions? What are their different types? Give example of each type.

What is demulsification? Name two demulsifiers.

Action of soap is due to emulsification and micelle formation. Comment.

Give four examples of heterogeneous catalysis.

What do you mean by activity and selectivity of catalysts?

Describe some features of catalysis by zeolites.

What is shape selective catalysis?

Explain the following terms: (i) Electrophoresis (ii) Coagulation (iii) Dialysis (iv) Tyndall effect.

Give four uses of emulsions.

What are micelles? Give an example of a micellers system.

Explain the terms with suitable examples:(i) Alcosol (ii) Aerosol (iii) Hydrosol

Comment on the statement that “colloid is not a substance but a state of substance”.