Question

Physisorption and Chemisorption Adsorption Characteristics
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Answer 1

Answer:

Explanation:

Physisorption and Chemisorption Adsorption Characteristics ;

Characteristics of physical adsorption:

1. This type of adsorption is caused by physical forces.
2. Physisorption is a weak phenomenon.
3. This adsorption is a multi-layered process.
4. Physical adsorption is not specific and takes place all over the adsorbant.
5. Surface area, temperature, pressure, nature of adsorbate effects physisorption.
6. Energy for activation is low (20 – 40 kg/mol).

Characteristics of chemical adsorption:

1. This type of adsorption is caused by chemical forces.
2. It is a very strong process.
3. This type of adsorption is almost a single-layered phenomenon.
4. Chemisorption is highly specific and takes place at reaction centres on the adsorbant.
5. Surface area, temperature, nature of adsorbate effects chemisorption.
6. Energy of activation is very high 40 – 400 kJ/mol.

Answer 2

Answer:

The characteristics of physisorption are: There is no specificity as any gas can be adsorbed onto the surface. Since the adsorption process is exothermic, the physical adsorption occurs readily at low temperature and decreases with increasing temperature (Le-Chatelier's principle).