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(a) Heat of adsorption is greater for ch...

(a) Heat of adsorption is greater for chemisorptions than physisorption. Why ?
(b) What is collodion?
(c) Differentiate between peptisation and coagulation.

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(a) In chemisorption, chemical bonds are present in the particles of adsorbate and adsobent. As a result, attractive forces are more in chemisorption that in physisorption in which the attractive forces are only van der Walls' forces. Therefore, heat of chemisorption is more than that of physisorption.
(b) A four percent solution of cellulose nitrate prepared in a liquid mixture of ethyl alcohol and dienyhyl ether (or simply ether) is known for as colloidion.
(c ) As a result peptisation, a precipitate gets coverted into colloidal sol. Coagulation is reverse in the sense that it converts a colloidal sol into precipitate. For details, consult section 23.
For details about peptisation, consult Section 10 For details about coagulation, consult Section 23.
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DINESH PUBLICATION-SURFACE CHEMISTRY -QUESTION FROM BOARD EXAMINATIONS
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  2. name the type of potential difference between fixed charged layer and ...

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  3. (a) Heat of adsorption is greater for chemisorptions than physisorptio...

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  4. Ferric chloride is applied to stop bleeding cut because

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  5. Give one main difference between lyophobic and lyphilic colloids.

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  6. Name two groups in which the phenomenon of catalysis can be divided. G...

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  7. Write differences between physisorption and chemisorption.

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  8. Define the following terms giving one example of each. (i) Electroph...

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  9. What is the particles size in a coloidal solution ?

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  10. Which of the two, adsorption or absorption, is surface phenomenon?

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  11. Write differences between physisorption and chemisorption.

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  12. Give reason for the following : (a) Rough surface of catalyst is mor...

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  13. What are the characteristics of the following colloids ? Give one exam...

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  14. Which aerosol depletes ozone layer?

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  15. Write differences between physisorption and chemisorption.

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  16. Write the dispersed phase and dispersion medium in the colloidal syste...

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  17. Out of Lyophilic and Lyophobic sols, which can be easily coagulated on...

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  18. Mechanism Of Enzyme Catalysis

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  19. What is the difference between sol and gel ?

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  20. What are enzymes ? Give two example with uses.

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