During the adsorption of krypton on activated charcoal at low temperature,which of the following thermodynamic conditions is true?

What is the range of enthalpy of adsorption in physical adsorption? $(kJ \, mol^{-1})$

Assuming Langmuir monolayer adsorption,the volume of nitrogen gas adsorbed on a sample of silica gel at $STP$ is $1.30 \, cm^3 \, g^{-1}$. The area occupied by a nitrogen molecule is $0.16 \, nm^2$. The surface area of silica gel per gram is ......... $m^2 \, g^{-1}$.

Adsorption is a phenomenon in which a substance

What will be the effect of an increase in temperature on physical adsorption?

Why is it important to have a clean surface in surface studies?