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प्रश्न
What is the role of adsorption in heterogenous catalysis?
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उत्तर
The role of heterogeneous catalysts can be explained in terms of adsorption of reactants on the surface of the catalyst.
The adsorption helps the reaction in the following ways:
(i) Adsorption increases the concentration of reactants on the surface of the catalyst. Due to increased concentration of the reactants, the reactions proceed rapidly.
(ii) Adsorbed molecules get dissociated to form active species like free radicals which react faster than molecules.
(iii) The adsorbed molecules are not free to move about and, therefore, they collide with other molecules on the surface.
(iv) The heat of adsorption evolved acts as energy of activation for the reaction (chemisorption).
Example: Adsorption of molecules of the reactant at the active site.
Occurrence of chemical reaction on the surface of catalyst
Desorption of product molecules
Example:
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संबंधित प्रश्न
Why are powdered substances more effective adsorbents than their crystalline forms?
Distinguish between the meaning of the terms adsorption and absorption. Give one example of.
Give reason why a finely divided substance is more effective as an adsorbent.
Write one similarity between Physisorption and Chemisorption
Give reasons for the following observations :
Powdered substances are more effective adsorbents.
How does chemisorption vary with temperature?
Which of the following compounds is formed when tungsten adsorbs oxygen gas?
Which of the following is an example of physisorption?
Which of the following is true about chemisorption?
Chromatography is based on the principle of ____________.
The extent of adsorption increases with the ____________.
Extent of physisorption of a gas increases with ______.
Physical adsorption of a gaseous species may change to chemical adsorption with ______.
What is the role of activated charcoal in gas mask used in coal mines?
Give an example where physisorption changes to chemisorption with rise in temperature. Explain the reason for change.
Which among the following is a false statement?
Assertion A : Activated charcoal adsorbs SO2 more efficiently than CH4.
Reason R : Gases with lower critical temperatures are readily adsorbed by activated charcoal.
In light of the above statements, choose the correct answer from the options given below.
Which of the following statements is incorrect regarding physisorptions?
