question_answer 10)

  What is the different between physical adsorption and chemisorption?

Answer:

 

S. No.	Physisorption (van der Wall’s Adsorption)	Chemisorption (Activated Adsorption)
1.	Forces of attraction between adsorbent and adsorbate are weak vander Waal’s forces.	Force between adsorbent and adsorbate are chemical forces.
2.	Heat of adsorption is lower (20-40 k cal/mole).	Heat of adsorption is high (80-240 k cal/mole)
3.	It is nonspecific in nature.	It is specific in nature.
4.	It is temporary and reversible.	It is permanent and irreversible.
5.	It occurs at low temperature and decreases with increase in temperature.	It occurs at high temperature.
6.	In this multimolecular layer is formed.	In this unimolecular layer is formed.