Nature and Concept

The following points set out more clearly the qualitative nature and concept of catalysis and catalysts  

This proposed catalytic mechanism (Chong and Sharpless, 1977) requires four reaction steps (3 bimolecular and 1 unimolecular), which take place on a molybdenum metal center (titanium and vanadium centers are also effective), to which various nonreactive ligands (L) and reactive ligands (e g., O-R) are bonded. Each step around the catalytic cycle is an elementary reaction and one complete cycle is called a turnover. 

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The dual sense of the epistemological concept of chemical elements has been the focus of much philosophical debate and research by contemporary philosophers of chemistry. Although this debate goes back to the 1931 paper by Paneth, the main idea was clearly already present in the Mendeleev corpus." It is therefore interesting to investigate to what extent the rare-earth crisis forced Mendeleev to change his points of view with regard to the nature and concept of elements. 

The following points summarise the nature and concept of catalysis ... 

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