To have a comprehensive answer you need to read this 800 pages book cited 19136 times:

http://image.sciencenet.cn/olddata/kexue.com.cn/upload/blog/file/2009/10/2009108131813830677.pdf

In case of chemisorption, adsorbate can form typically inner-sphere complexes with the surface or strong electrostatic interaction exist while in case of physisorption adsorbate can form outer sphere complexes with the substrate or van der Waals force, H-bonding, weak covalent bonding exist.

One describes with PFO and the other with PSO. Although probably the vice versa. There is also PTO and PNO to choose from. Regards,

Physical adsorption is weak Vander wall force adsorption of molecules on the material while chemical adsorption is strong chemical bond.

Knowledge about the adsorption process (as Yurii wrote) was established a long time ago. Unfortunately, now, many create a false image of the adsorption process by linking its mechanism to PFO and PSO. Hence my comment above. Regards,

Physical adsorption entails weak van-der waal forces (adsorption potentials) binding the adsorbate to the adsorbent surface and can be identified using adsorption energy values calculated from Dubinin-Raduskevitch Isotherm relation (low E-physical adsorption) as well as low activation energy (spontaneous). While chemical adsorption is the binding of adsorbate to surface functional groups on the adsorbent surface via chemical bonds ( large E-chemical adsorption) and is also correlated by the Langmuir isotherm relation (monolayer formation) and pseudo second order kinetic model fit. Experimentally, a simple batch desorption test using a chemical eluent to remove the adsorbate from the saturated adsorbent will reveal the adsorption mechanism. If chemical adsorption is predominant, then insignificant amount of adsorbate will be recovered from the spent adsorbent due to the new surface complexes formed (irreversible process), if physical then significant adsorbate will be removed from the adsorbent as the binding forces are weak van der waals forces.

Directly Quoting Dr. Miroslaw Grzesik, The expression exp(-Bɛ2) in the D-R isotherm depends on temperature. For B greater than zero it is a decreasing function with respect to temperature, and for B less than zero it is an increasing function. The first case relates to physisorption in the gas-solid system, and the second to chemisorption in the same system. Hence, if B is positive (physisorption), use E=1/√2B, and if negative (chemisorption), use E=1/√-2B. There are no problems with units, because the exponent: -Bɛ2 is dimensionless. One more thing: the D-R equation before and after taking logarithm on both sides is nonlinear.

Physical adsorption is performed at low temperatures by a weak bonding force called van der Waals. The heat released from this adsorption does not exceed 5 kcal/mol. This adsorption increases with increased gas pressure and decreases with high temperature. The gas is more absorbent as it is easy to liquefy. Depending on the case, the gas can have a monolayer or multi-particle layer on the surface.

Chemical adsorption

It is a bond between the surface particles of a metal (or of any other substance with high surface energy), a substance of a maze and another substance (gas or liquid) in contact with it (an excess material). These bonds are almost as strong as conventional chemical bonds, much stronger than the van der Waals forces characteristic of physical adsorption. The heat released from this adsorption is about 50-100 kcal/mol, and chemically absorbed molecules are often replaced. For example, molecular hydrogen chemically adsorbs to surface Metallic in the form of hydrogen atoms. A practical example of chemical adsorption is the lubrication or lubrication of the metal moving parts of the machinery. Chemical adsorption requires solid objects with high surface energies such as nickel, silver, platinum and iron. Chemical adsorption plays a very important role in the interpretation of heterogeneous catalysis. It is worth mentioning that physical and chemical adsorption can occur simultaneously at the surface, especially at low temperatures. For example, carbon dioxide adsorption on SiO2-NiO surface.

To find out the difference between these two types, you can read the attached lecture.

watch the following video:

https://youtu.be/cwOq6EeygV8

See the following book:

Introduction to Adsorption, Basics, Analysis, and Applications, by Chie Tien, (2019)

See the following website:

https://www.researchgate.net/deref/https%3A%2F%2Fstudy.com%2Facademy%2Flesson%2Fchemical-vs-physical-adsorption.html

Physical adsorption takes place at a suitable temperature-pressure in a gas solid system, where as chemisorption occurs whenever the gas is capable of forming chemical bonding with substrate surface.

Here is link

https://youtu.be/wWIZyxrp04I

With reference to the above link, it is worth remembering that the mere good agreement of the Langmuir isotherm with the equilibrium data does not allow for an unequivocal specification of the adsorption mechanism. The hypotheses formulated here must be supported by the results of physicochemical tests of the adsorbent surface.