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Give the mechanism of heterogeneous cata...

Give the mechanism of heterogeneous catalysed reaction.

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Mechanism of enzyme catalysis can be satisfactorily explained on the basis of lock-and-key model as follows.
There are a number of cavities present on the surface of enzymes. These cavities are of characteristic shape and possess active groups such as `-NH_2`, COOH, -SH, OH, etc. These are actually the active centres on the surface of enzyme. The molecules of the reactant (substrate), which have complementary shape, fit into these cavities just like a key fits into a lock. On account of the presence of active groups, an activated complex is formed which then decomposes to yield the products.

Thus, the enzyme-catalysed reactions may be considered to proceed in two steps.
Step 1 : Binding of enzyme to substrate to form an activated complex.
`E + S to ES^(cancel=)`
Step 2 : Decomposition of the activated complex to form product.
`ES^(cancel=) to E + P`
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BETTER CHOICE PUBLICATION-SURFACE CHEMISTRY -Question Bank
  1. How do enzymes differ from catalysts ?

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  2. What are Enzymes ? Give important characteristics of enzyme catalysis.

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  3. Give the mechanism of heterogeneous catalysed reaction.

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  4. Explain two applications of enzymes.

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  5. What are colloids ?

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  6. which are the properties of colloidal solution ?

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  7. What is the difference between true solution and colloidal solution?

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  8. Give three differences between suspension and colloid solution.

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  9. Name the dispersed phase and dispersion mediumin fog.

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

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  11. What are lyophilic and lyophobic sols ? Give one example of each. Why ...

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  12. What are gels ? Give an example of elastic and non-elastic gel.

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  13. How will you differentiate Lyophilic colloids from Lyophobic colloids?

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  14. Lyophillic colloids are more stable than lyophobic colloids. Explain.

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  15. What is the difference between multimolecular and macromolecular collo...

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  16. Give three differences between multimolecular colloids and macromolecu...

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  17. What are micelles ? Give one example of a micellar system.

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  18. Explain the mechanism of the cleansing action of soaps

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  19. Discuss cleansing action of soap by micelle formation.

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  20. Write short note on peptisation.

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