Free NCERT Solutions For Class 12 Chemistry Chapter 5 : Surface Chemistry Free PDF Download
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?
What modification can you suggest in the Hardy-Schulze law?
Distinguish between the meaning of the terms adsorption and absorption. Give one example of each.
What is the difference between physisorption and chemisorption?
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?
Discuss the effect of pressure and temperature on the adsorption of gases on solids.
What are lyophilic and lyophobic sols? Give 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?
How are colloids classified on the basis of
(i) Physical states of components
(ii) Nature of dispersion medium and
(iii) Interaction between dispersed phase and dispersion medium?
Explain what is observed
(i) When a beam of light is passed through a colloidal sol.
(ii) An electrolyte, NaCl is added to hydrated ferric oxide sol
(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 demulsiffiers.
Give four examples of heterogeneous catalysis.
Describe some features of catalysis by zeolites.
What is shape selective catalysis?
Give four uses emulsions.
What are micelles? Give an example of a micelle system.
Comment on the statement that colloid is not a substance but a state of substance”.