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Standard electrode potential. In electrochemistry, standard electrode potential , or , is a measure of the reducing power of any element or compound. The IUPAC "Gold Book" defines it as; "the value of the standard emf (electromotive force) of a cell in which molecular hydrogen under standard pressure is oxidized to solvated protons at the left ...
Standard electrode potential (data page) The data below tabulates standard electrode potentials (E °), in volts relative to the standard hydrogen electrode (SHE), at: Temperature 298.15 K (25.00 °C; 77.00 °F); Effective concentration (activity) 1 mol/L for each aqueous or amalgamated (mercury-alloyed) species; Unit activity for each solvent ...
Electrode potential. In electrochemistry, electrode potential is the voltage of a galvanic cell built from a standard reference electrode and another electrode to be characterized. [1] By convention, the reference electrode is the standard hydrogen electrode (SHE). It is defined to have a potential of zero volts.
The hydrogen electrode is based on the redox half cell corresponding to the reduction of two hydrated protons, 2H+(aq), into one gaseous hydrogen molecule, H2 (g). General equation for a reduction reaction: The reaction quotient (Qr) of the half-reaction is the ratio between the chemical activities (a) of the reduced form (the reductant, ared ...
Nernst equation. In electrochemistry, the Nernst equation is a chemical thermodynamical relationship that permits the calculation of the reduction potential of a reaction (half-cell or full cell reaction) from the standard electrode potential, absolute temperature, the number of electrons involved in the redox reaction, and activities (often ...
The standard potential for the reaction is then +0.34 V − (−0.76 V) = +1.10 V . The polarity of the cell is determined as follows. Zinc metal is more strongly reducing than copper metal because the standard (reduction) potential for zinc is more negative than that of copper.
Electrochemistry. English chemist John Daniell (left) and physicist Michael Faraday (right), both credited as founders of electrochemistry. Electrochemistry is the branch of physical chemistry concerned with the relationship between electrical potential difference and identifiable chemical change. These reactions involve electrons moving via an ...
The reference half cell consists of a redox standard of known potential. The standard hydrogen electrode (SHE) is the reference from which all standard redox potentials are determined, and has been assigned an arbitrary half cell potential of 0.0 V. However, it is fragile and impractical for routine laboratory use.