Define adsorption. Write any two features which distinguish physi… - Vidyadip

Question

Define adsorption. Write any two features which distinguish physisorption from chemisorption.

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Answer

Adsorption- The phenomenon of attraction and retention of the molecules of a substance on the surface of a liquid or a solid resulting into a higher concentration of the molecules on the surface is called adsorption.

Physisorption	Chemisorption
It usually takes place at low temperature and decreases with increasing temperature.	It takes place at relatively high temperatures.
It is not very specific i.e. all gases are adsorbed on all solids to some extent.	It is highly specific and takes place when there is some possibility of compound formation between the adsorbate and the adsorbent molecules.
Multi Molecular layers may be formed on the adsorbent.	Usually mono-molecular layer is formed on the absorbent.

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