Teaching of Redox Reactions Starting from Iron-Sulphur Theory of the Origin of Life

摘要

The iron-sulphur or chemoautotrophic theory of the origin of life on Earth starts from the oxidation of FeS into FeS_(2) by H_(2)S. The released electrons and the catalytic surface of FeS particles are used for the synthesis of organic compounds from simple reactants, e.g. methanethiol from carbon dioxide and pyruvic acid from carbon monoxide. Beside these two reactions, the reduction of nitrogen into ammonia, and the synthesis of alanine from ammonia and pyruvic acid, using Fe(III) as oxidative agent were also described. Presentation of redox reactions in this way is aimed to animate students for learning redox processes as well as to familiarize them with new theories of the origin of life.