A homogeneous catalyst is a substance that speeds up a chemical reaction while being in the same phase, or state, as the reactants. This means that if the reactants are in a liquid form, the catalyst will also be in liquid form. Because they are mixed together, homogeneous catalysts can provide a more uniform reaction environment, often leading to higher reaction rates and better selectivity for desired products. These catalysts are commonly used in various industrial processes, such as the production of sulfuric acid and in organic synthesis. One well-known example of a homogeneous catalyst is transition metal complexes, which can facilitate reactions by forming temporary bonds with reactants, thereby lowering the energy barrier needed for the reaction to occur.