Question

The nature of bonding forces in adsorption :

• A. are purely physical such as van der Waals forces.
• B. are purely chemical.
• C. can be both chemical and physical.
• D. None of the above

Answer 1

The correct option is C can be both chemical and physical.

The exact nature of the bonding depends on the details of the species involved but the adsorption process is generally classified as physisorption and chemisorption.

In physisorption, adsorbate and adsorbent are binds by van der Waal's force of attraction. There is no bond formation in physisorption.
Accumulation of dust on window panes of cars is an example of physisorption.

In chemisorption, chemical bonds are formed between adsorbate and adsorbent.
Paint on the metal surface is an example of chemical adsorbtion.

Hence, adsorption can occurs by both physical and chemical bonding.