The choice of catalyst depends on the specific reaction and conditions. Catalysts can be broadly classified into homogeneous and heterogeneous catalysts. Homogeneous catalysts are in the same phase as the reactants, usually in a solution, while heterogeneous catalysts are in a different phase, often solid in contact with liquid or gas reactants. The decision involves evaluating the advantages and disadvantages of each type, such as ease of separation, activity, and stability.
