Physisorption:
(a)The forces operating are weak vander Waal’s forces
(b)The heat of adsorption is low 20-40 KJ Mol-1
(c) Does not require any activation energy
(d) Forms multimoleculer layer
Chemisorption:
(a) Forces acting are similar to those of chemical bonds
(b) The heat of adsorption is high 80-240 KJ Mol-1
(c) Requires activation energy
(d) Forms unimolecular layer