Oxidation-reduction reactions in geochemistry

Abstract

There are more than hundred elements in the periodic table and many of them are associated with various geochemical processes. Most of the elements can show more than one oxidation states, therefore, reactions involving oxidation and reduction are of very much importance in geochemistry. Since every change (chemical or physical) is associated with the change of energy, hence for every single process, there should be a reliable way for quantitative measurement of energy change. In case of any redox process, the energy change can be quantitatively expressed in terms of reduction potential of that process. For better understanding of a geochemical process, previously known reduction potentials can be used. The main importance of reduction potentials in geochemistry is for understanding the frequent concentration and enrichment of various elements in deposits formed under extremely reducing or oxidizing conditions.