Mechanism of Enzyme Catalysis The substance on which the enzyme acts is called the substrate. The enzyme molecule is a protein chain that acquires a shape such that the substrate can fit into its structure…

Characteristic Properties of Enzyme Catalysis Enzymes have a number of characteristic properties that make them efficient and specific catalysts for many biological reactions. Enzyme catalysis is the increase in the rate of a chemical reaction…

Enzyme Catalysis Many chemical reactions associated with living organisms are accelerated by a group of closely related substances called enzymes. Enzymes play a dominant role in biochemical reactions responsible for our digestion and metabolism of…

Mechanism of Acid-Base Catalysis The addition of proton or its removal must be associated with acid-base catalysis; this is because for most cases an acid may be treated as a proton donor and a base…

Acid-Base Catalysis Many organic reactions in solution are known to be catalyzed by acids or bases or both. These reactions form an important class of homogeneous catalytic reactions and the phenomenon is treated as general…

Catalytic Hydrogenation of Ethylene The five steps are illustrated in figure for the catalytic hydrogenation of ethylene to form ethane using finely divided nickel catalyst. Fig: Schematic diagram of five steps in heterogeneous catalyst Both…

Experiment Explanation by Catalytic Adsorption Theory The adsorption theory satisfactorily explains the following: (i) The specific nature of the catalyst and the change in the course of reaction by changing the surface: When the surface…

The role of promoters in Catalyst Adsorption A small quantity of promoter is sufficient to increase the activity of the catalyst to a large extent. In Haber-Bosch synthesis of ammonia, small amounts of molybdenum, high…

Intermediate compound theory: This theory was proposed by Clement and Desormes in 1806. The essential feature of the theory is that the catalyst chemically combines with one of the reactants to form an unstable active…

Adsorption theory: This theory can be applied to heterogeneous catalysis only. As the name suggests the reactant is adsorbed on the surface of the catalyst and the effective concentration of the reactant is generally increased…