interesting question

Hi S. Jayapandi,

In determining the kinetic model, it all depends on what is the rate-determining step in the whole process (ie. the elementary step with the highest barrier - for nice illustration, see https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Kinetics/02%3A_Reaction_Rates/2.06%3A_Reaction_Rates-_A_Microscopic_View).

So, if there is a LH-like step in your reaction, and the LH-like step has the highest barrier, the LH model will be the best model to describe the reaction.

Dear S . Jayapandi

I hope you are OK.

All depend on the mechanism that you have in the reaction. In many of the cases LHHW formalism is used for further explanation of the heterogeneous reaction. But, it does not imply that necessary LHHW is the only possible or at least is the more "adequate".

All depend on the type of reaction and the kind of mechanism that you are trying to fit. Even, in many of the cases, although data is fitting better for a model many times do not have physical meaning.

Then, the most appropriate way is (To choose the correct model):

a) Take your experimental data.

b) Adjust your data at different models (considering different determining steps) c) Determine the statistical values for each model and see the physical meaning.

d) Compare and conclude.

Both LHHW and Eley-Rideal models are adequate for explanation for your reaction but before seeing statistical data and correct fitting.

If you have any doubt please let me know.

With kind regards,

Julián Sánchez.

Following steps must be taken into consideration in the selection of an appropriate model:

1) Adjust your data at different models on the basis of different rate determining steps)

2) Determine the statistical values for each model and see the physical meaning.

3) Conclude your results by critical analysis of data.

Thank you very much for all your great answers.