What is an adsorption isotherm? Describe Freundlich adsorption isotherm.

Adsorption Isotherm- The variation in the amount of a gas adsorbed by the adsorbent with pressure at constant temperature can be expressed by the curve . This curve is known as Adsorption Isotherm.


Freundlich adsorption isotherm- Freundlich gave an empirical relationship between the quantity of gas adsorbed by a unit mass of solid adsorbent And pressure at a particular temperature.


x/m = k P1/nm





Where x is the mass of gas adsorbed on mass m of the adsorbent pressure P. k and n are constants depend on nature of adsorbent. This relationship is expressed in the form of curves where the mass of the gas adsorbed per gram of adsorbent is plotted against pressure.



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