Question

Which of the following statements about physisorption is correct?

• A. It always results in a monolayer.
• B. It is reversible in nature.
• C. It involves van der waals interaction between the adsorbent and the adsorbate.
• D. It involves small enthalpy of adsorption as compared to chemisorption.

Answer 1

Answer: (B), (C), (D)

The correct options are
B It is reversible in nature.
C It involves van der waals interaction between the adsorbent and the adsorbate.
D It involves small enthalpy of adsorption as compared to chemisorption.

Physisorption processes are all reversible since they only involve the formation of weak bonds between the adsorbent and the adsorbate. The enthalpy of adsorption is also less because no chemical reaction takes place.