Phy si sorption

Absorption and Adsorption are not the sam e Absorption is the incorporation (sometimes even consumption) of a matter into a medium (light is absorbed/consumed by a pigment, gas is ab-sorbed/dissolves into a liquid), whereas Adsorption is the adhesion of matter onto a—usually solid—surface (dust on furniture, steam on windscreen, vapours on any solid surface...) Adsorption is further subdivided in chemisorption, in which the matter is bound to a surface by chemical bonds, and phy si sorption, in which the bonding is only a physical effect. The transition between both is fluent. 

Steele, W.A., Computer simulation of phy si sorption. Summary — Theory and Models, in Fundamentals of Adsorption, A.L. Myers and G. Belfort (eds.). Engineering Foundation, New York, 1983, pp. 597, 743. 

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