oxidation potential (electrode potential, reduction potential; Eθ) The energy change, measured in volts, required to add or remove electrons to or from an element or compound. The reference reaction is the removal of electrons from hydrogen in a standard hydrogen half-cell (i.e. H2(gas) at 1 atm pressure delivered to a 1.0 M solution of H+ ions at 25°C, into which a platinum electrode has been inserted): H2 → 2H+ + 2e−, This energy change is given the value of zero. The oxidation potential of other species are determined relatively by measuring the potential difference between a half-cell containing an aqueous solution of the oxidized and reduced forms of the test substance, and the standard hydrogen half-cell. For example, for Fe2+ → Fe3+ + e−, Eθ = 0.77, for Mn2+ → Mn3+ + e−, Eθ = 1.51. With decreasing values of oxidation potential, the reduced form of a couple (e.g. Fe2+) will itself reduce the oxidized form of a couple with a higher oxidation potential (e.g. Mn3+). The oxidation potentials obtained under these controlled conditions are called standard electrode potentials, or sometimes standard reduction potentials. Compare REDOX POTENTIAL.
More From encyclopedia.com
Reduction Potential , Skip to main content reduction potential Potential Instability , Skip to main content potential instability Chemical potential , chemical potential See WATER POTENTIAL. chemical potential See water potential. Action Potential , Action potentials are the electrical pulses that allow the transmission of information within nerves. An action potential represents a change in elec… Electrochemistry , Electrochemistry Electrochemistry deals with the links between chemical reactions and electricity. This includes the study of chemical changes caused… Pressure Potential , Skip to main content pressure potential
About this article
Updated About encyclopedia.com content Print Article
You Might Also Like