What is meant by heterogeneous catalysis? - Leaving Cert Chemistry - Question (d) - 2007

Heterogeneous catalysis refers to a process wherein the reactants and the catalyst exist in different phases. Typically, this means that one of the components, either the reactants or the catalyst, is in a solid state while the other is in a gaseous or liquid state.

In this context, the boundary between the reactants and the catalyst plays a crucial role. The reaction occurs at the interface of these two phases, allowing for increased reactivity and efficiency due to the larger surface area provided by the solid catalyst.

The interfacial reactions often lead to significant enhancements in reaction rates as they facilitate the proper orientation and transition state formation, which are essential for the conversion of reactants into products.