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Electrode potentials of successive elementary half-reactions cannot be directly added. However, the corresponding Gibbs free energy changes (∆G°) must satisfy ∆G° = – z FE°, where z electrons are transferred, and the Faraday constant F is the conversion factor describing Coulombs transferred per mole electrons. Those Gibbs free energy ...
The reactivity series is sometimes quoted in the strict reverse order of standard electrode potentials, when it is also known as the "electrochemical series". [8] The following list includes the metallic elements of the first six periods. It is mostly based on tables provided by NIST.
The difference can be measured as a difference in voltage potential: the less noble metal is the one with a lower (that is, more negative) electrode potential than the nobler one, and will function as the anode (electron or anion attractor) within the electrolyte device functioning as described above (a galvanic cell).
When an oxidizer (Ox) accepts a number z of electrons ( e −) to be converted in its reduced form (Red), the half-reaction is expressed as: Ox + z e − → Red. The reaction quotient (Q r) is the ratio of the chemical activity (a i) of the reduced form (the reductant, a Red) to the activity of the oxidized form (the oxidant, a ox).
From Wikipedia, the free encyclopedia. Redirect page. Redirect to: Standard electrode potential (data page)
Bipolar electrochemistry scheme. 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-hand electrode".
Since Δ r G o = -nFE o, the electrode potential is a representation of the Gibbs energy change for the given reduction. The sum of the Gibbs energy changes for subsequent reductions (e.g. from O 2 to H 2 O 2 , then from H 2 O 2 to H 2 O) is the same as the Gibbs energy change for the overall reduction (i.e. from O 2 to H 2 O), in accordance ...
Chronoamperometry is typically carried out in unstirred solution and at the fixed electrode, i.e., under experimental conditions avoiding convection as the mass transfer to the electrode. On the other hand, voltammetry is a subclass of amperometry, in which the current is measured by varying the potential applied to the electrode.