Which of the following statement is incorrect regarding physissorptions?
- It occurs because of van der Waal's forces.
- More easily liquiefiable gases are adsorbed readily.
- Enthalpy of adsorption (ΔHadsorption) is low and positive.
- Under high pressure it results into multi molecular layer on adsorbent surface.
Enthalpy of adsorption in physisorption is negative:
ΔG = ΔH - TΔS
As the entropy decreases (ΔS = -ve) the ΔH must be negative having a high magnitude. Therefore, the spontaneous adsorption will have negative enthalpy change.
The correct option is C.