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Standard hydrogen electrode. In electrochemistry, the standard hydrogen electrode (abbreviated SHE), is a redox electrode which forms the basis of the thermodynamic scale of oxidation-reduction potentials. Its absolute electrode potential is estimated to be 4.44 ± 0.02 V[ 1 ] at 25 °C, but to form a basis for comparison with all other ...
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.
e. In chemistry, pH (/ piːˈeɪtʃ / pee-AYCH), also referred to as acidity or basicity, historically denotes " potential of hydrogen " (or "power of hydrogen"). [ 1 ] It is a logarithmic scale used to specify the acidity or basicity of aqueous solutions. Acidic solutions (solutions with higher concentrations of hydrogen (H+) ions) are ...
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 ...
However, the total cell potential (difference between oxidation and reduction half cell potentials) will remain 1.23 V. This potential can be related to Gibbs free energy (ΔG) by: ΔG°cell = −nFE°cell Where n is the number of electrons per mole products and F is the Faraday constant. Therefore, it takes 475 kJ of energy to make one mole of ...
The lower graph shows the logarithmic plot for different values of α (Tafel plot). The Butler–Volmer equation is: or in a more compact form: where: : electrode current density, A/m 2 (defined as j = I/S) : exchange current density, A/m 2. : electrode potential, V. : equilibrium potential, V.
E pzc is the electrode potential difference with respect to the point of zero charge, E σ=0; E is the potential of the same electrode against a defined reference electrode in volts; E σ=0 is the potential of the same electrode when the surface charge is zero, in the absence of specific adsorption other than that of the solvent, against the ...