Redoxchemie

Redoxchemie, or redox chemistry, is the study of oxidation-reduction reactions in which electrons are transferred between chemical species or their oxidation states change. It encompasses chemical, electrochemical, and biological redox processes and is fundamental to energy conversion, metabolism, corrosion, and the environmental behavior of elements.

Central ideas include oxidation states that assign electron ownership, reducing agents (which donate electrons) and oxidizing agents (which accept electrons), and redox couples that describe the two forms of a half-reaction. Standard redox potentials (E°) quantify a species’ tendency to gain or lose electrons, and the Nernst equation links potentials to concentrations and conditions.

Methods: redox titration using color indicators or potentiometric endpoints; electrochemical techniques such as cyclic voltammetry; spectroscopic probes of oxidation state; and pH-dependent equilibria.

Applications: energy storage and conversion (batteries, fuel cells), electroplating and metal refining, corrosion protection, and environmental remediation. In biology, redox reactions underpin respiration and photosynthesis, with carriers such as NAD+/NADH and FAD/FADH2 mediating electron transfer along membranes.

History: the concept of redox derives from reduction and oxidation, formalized in the 18th–19th centuries as scientists recognized simultaneous electron transfer; Wilhelm Ostwald and others helped establish the modern framework.