ESS102H1 Lecture Notes - Aquifer, Hydronium, Bromine
Document Summary
The importance of redox (i. e. , oxidation-reduction) processes in biogeochemistry cannot be over emphasized. These are reactions that involve the transfer of electrons between one or more chemical species. Life would not exist without oxidation-reduction reactions, and the intense biological and geochemical cycling of redox sensitive elements that essentially define the uniqueness of the earth system would not occur. Everything we appreciate about our planet depends on oxidation-reduction reactions. Many elements occur in nature in more than one oxidation state. The major elements with such redox behavior include h, o,c,s,n, and fe. In some systems, mn is also a major redox element. As a general rule, most reactions that involve electrons also involve protons. This is a basic cause of acid mine drainage. Conversely, reduction generally consumes protons, and the ph rises. In redox reactions, electrons are transferred from an electron-donor or reductant to an electron acceptor or oxidant.
