Name: Colloids and Their Properties
Uploaded: 2019-07-19
Duration: 4 min 49 s
Description: Have you ever come across a substance that is not a suspension but also not a true solution? It's a colloidal suspension. Let's learn about the properties of...

Question

Explain the mechanism of the term: Adsorption

Accepted Answer

Mechanism of Adsorption:
(i) Surface Forces Adsorption arises due to the fact that the surface particles of the adsorbent are not in the same environment as the particles inside the bulk. Inside the adsorbent, all the forces acting between the particles are mutually balanced, but on the surface, the particles are not surrounded by atoms or molecules of same kind on all sides.

The extent of adsorption increases with the increase of surface area per unit mass of the adsorbent at a given temperature and pressure.

(ii) Heat of Adsorption During adsorption, there is always decrease in surface energies.

(iii) Entropy Change during Adsorption and Adsorption Equilibrium The molecules of the gas are held on the surface of the solid adsorbent hence, entropy decreases (because their freedom of movement become restricted), $AS$ is also negative and $TAS$ is positive.

Explain the mechanism of the term: Adsorption

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