Respuesta :
Explanation:
Difference between physisorption and chemisorption are as follows.
Physisorption:
- Due to Vander waal forces, adsorbate is held on the surface of adsorbent.
- Enthalpy of adsorption is low, that is, 20 kJ/mol.
- Physisorption is reversible in nature.
- It occurs at low temperature and decreases with increase in temperature.
- At the surface, multi-molecular layer of adsorbate occurs.
- There is no need of activation energy in physisorption. Also, it requires high pressure and decrease in pressure leads to desorption.
- All gases are adsorbed by adsorbent as physisorption is not specific.
Chemisorption:
- Due to chemical bonds, molecules of adsorbate and adsorbent are held together.
- Enthalpy of adsorption is high, that is, 200 kJ/mol.
- It is irreversible in nature.
- It occurs ate relatively high temperature.
- Chemisorption leads to the formation of only monomolecular layers.
- It needs high activation energy. And, high pressure is favorable abd decrease in pressure does not cause desorption.
- Chemisorption is highly specific in nature.
