[appelsinbla]

First of all, let me thank all those who actively manage this forum. I would like to know why transition metals are used as catalysts in many chemical reactions? What are the possible reasons that make them suitable for this purpose. Thanks.

[Schrödinger]

One huge reason is the variable oxidation state. The basic necessity of a catalyst is to be chemically inert when it comes to the overall reaction. Meaning, it may react with the reactants in the meanwhile. But then the reaction is done, it should have returned to its original state.

With variable oxidation states, the transition metal can oxidized during the reaction (thus reducing something else) and in this new found state, react with reactants and get reduced to its original state later. Thereby, remaining 'inert'