Question

Freundlich adsorption theorem is valid for chemispotion.
A. True
B. False

Answer 1

Hint:The curve that expresses any variation in the amount of gas absorbed by the absorbent with pressure at constant pressure is known as Adsorption Isotherm . The adsorption isotherm which gives an empirical relationship between the amount of which is gas adsorbed by a unit mass of the solid adsorbent and pressure at a particular temperature is called the Freundlich Adsorption Isotherm.

Complete step by step solution:
> Freundlich adsorption isotherm, also known as Freundlich equation, shows an empirical relation between the concentrations of a solute on the surface of an adsorbent to the concentration of the solute in the liquid with which it is in contact.
> The Freundlich equation or Freundlich adsorption isotherm is mathematically expressed as
$${\displaystyle \frac{x}{m}}=K{p}^{{\displaystyle \frac{1}{n}}}$$
The other forms of this expression are
$$\log {\displaystyle \frac{x}{m}}=\log K+{\displaystyle \frac{1}{n}}\log p$$
Where x=mass of the adsorbate and m=mass of the adsorbent.
P=Equilibrium pressure of adsorbate.
$${\displaystyle \frac{x}{m}}=K{c}^{{\displaystyle \frac{1}{n}}}$$
$$\log {\displaystyle \frac{x}{m}}=\log K+{\displaystyle \frac{1}{n}}\log c$$
C= Equilibrium concentration of adsorbate in solution.
K and n are constants for a given adsorbate and adsorbent at a given temperature. At high pressure $${\displaystyle \frac{1}{n}}=0$$, so the extent of adsorption becomes independent of pressure.
- Chemisorption is an adsorption which involves chemical reaction between surface and the adsorbent. In contrast with chemisorption is physisorption. Langmuir & BET adsorption isotherm is for physisorption. Langmuir Adsorption is related to monolayer adsorption while Fruendlich adsorption is related to multilayer adsorption.
- Thus we can see that this isotherm is valid for chemisorptions. The above given statement is true.

Note: Freundlich adsorption isotherm is based on chemisorptions. While Langmuir adsorption isotherm is based on physisorption.