In Langumir's model of adosrption of a gas on a solid surface :

Options

A. the rate of dissociation of adsorbed molecules from the surface does not depend upon the surface covered.
B. the adsorption at a single site on the surface may involve multiple molecules at the same time
C. the mass of gas striking on a given area of surface is independent of the pressure of the gas
D. the mass of gas striking on a given area of surface is proportional to the pressure of the gas

Answer

D

Explanation

Assuming the formation of a monolayer of the adsorbate on the surface of the adsorbent, Langmire derived that the mass of the gas adsorbed per gram of the adosrbent is related to the equilibrium pressure as follows:
`(x)/(m)=(aP)/(1+bP)`
or `(1)/(x//m)=(1+bP)/(aP)=(1)/(aP)+(b)/(a)`
Under high pressure, `bPgt gt1` . hence
or `(x)/(m)=(aP)/(bP)=(a)/(b)`