Illustrated Glossary of Organic Chemistry

Catalyst: A substance that increases reaction rate by altering the reaction mechanism. A true catalyst is regenerated at some point in the reaction mechanism, and need only be present in substoichiometic amount. In addition, a true catalyst does not alter ΔG or Keq for the reaction.

This catalytic hydrogenation reaction is catalyzed by platinum.

This bromination reaction follows the electrophilic aromatic substitution mechanism, and is catalyzed by FeBr3.