Standard electrode potential electrochemical series

Normalpotentiale chem standard electrode potentials (tabular series), standard reduction potentials, electrochemical series (of metals) Spannungsrelaxation polym stress relaxation Spannungsriss stress crack... 

When metals are arranged in the order of their standard electrode potentials, the so-called electrochemical series of the metals is obtained. The greater the negative value of the potential, the greater is the tendency of the metal to pass into the ionic state. A metal will normally displace any other metal below it in the series from solutions of its salts. Thus magnesium, aluminium, zinc, or iron will displace copper from solutions of its salts lead will displace copper, mercury, or silver copper will displace silver. 

Note the observed phenomena. Write the molecular and net ionic equations of the reactions occurring between the metals and the salts. Arrange the metals in a series according to their activity (the electrochemical series), writing down the values of their standard electrode potentials (see Appendix 1, Table 2). What place does hydrogen occupy in this series ... 

Compare the chemical activity of the studied alkali metals. What does it depend on Why does lithium head the electrochemical series of the metals Find the values of the standard electrode potentials of the alkali metals (see Appendix 1, Table 21). 

Referring to a list of standard electrode potentials, such as in Table 8.3, one speaks of an electrochemical series, and the metals lower down in the se-ries(with positive electrode potentials) are called noble metals. Any combination of half-reactions in an electrochemical cell, which gives a nonzero E value, can be used as a galvanic cell (i.e., a battery). If the reaction is driven by an applied external potential, we speak of an electrolytic cell. Reduction takes place at the cathode and oxidation at the anode. The reduction reactions in Table 8.3 are ordered with increasing potential or pe values. The oxidant in reactions with latter pe (or E°) can oxidize a reductant at a lower pe (or ) and vice versa for example, combining half-reactions we obtain an overall redox reaction ... 

The electrochemical series (Table 8.3) gives thermodynamic information on the so-called nobility of various metals the higher the standard electrode potential, the more noble is the metal, silver being more noble than Cu and Cu being more noble than Zn. 

The electrochemical series tabulates standard electrode potentials. Some sources call the electrochemical series oxi-dation/reduction potentials, electromotive series, and so on. The reference state of electrochemical series is the hydrogen evolution reaction, or H+/H2 reaction. Its standard electrode potential has been universally assigned as 0 V. This electrode is the standard hydrogen electrode (SHE) against which all others are compared. For example, the standard electrode potential of the Fe/Fe2+ reaction is —0.440 V and that of Cu/Cu2+ reaction is +0.337 V. The standard electrode potentials are calculated from Gibbs free energy values by Eq. (8) that is applicable only in the above-mentioned standard state. 

Electrochemical series - An arrangement of reactions which produce or consume electrons in an order based on standard electrode potentials. A common arrangement places metals in decreasing order of their tendency to give up electrons. 

The considered electrochemical model has brought us to certain conclusions on the mechanism of polymer polarization in the M1-P-M2 systems. It is evident that definite electrode potentials are established on metals faces in contact with the polymer material. These potential values are affected by the work function of the electrons and metal afEnity to the corresponding structural elements of the polymer lining. These potentials are noncoincident with a standard electrochemical series of metals. This is natural, since the properties of polymer materials as electrolytes are not identical to those of salt solutions of the corresponding metals, for which the standard electrode potentials of metals are determined. The studied metals in pairs separated by the PVB lining are arranged in the following series ... 

Characteristic diagrams of polarization current variations during pendulum start and stop are illustrated in Fig. 4.15. A jump in polarization current was observed at the moment when the pendulum was set into motion. This jump is attributed to the disturbance of the film products of electrochemical reaction occurring on the tray surface during motion of the prism. Its value, all other conditions being equal, diminished within the Cu-steel-Al series and corresponds to the position of these metals in the series of the standard electrode potentials [19]. 

Table 5.12 Electrochemical series of metals (standard electrode potential in V).

The electrochemical series tabulates standard electrode potentials. Some sources call the electrochemical series oxi-dation/reduction potentials, electromotive series, and so on. The reference state of electrochemical series is the hydrogen evolution reaction, or reaction. Its... 

The standard electrode potentials for some common metals are given in Table 19.1. Note that the half-cell reactions are written as reduction processes the metal ions are gaining electrons. The standard electrode potentials are therefore sometimes known as standard reduction potentials. This arrangement of metals (and hydrogen) in order of decreasing standard electrode potential is known as the electrochemical series. It is very similar in arrangement to the activity series (Chapter 9). 

The electrochemical series has been extended to give the redox series (Table 19.2), which includes the standard electrode potentials of redox systems in which transition metals are present in different oxidation states. 

The electrochemical series [Ch ter 10, Table 10.13] or, in fact, a list of the standard electrode potentials for reduction half-reactions can be very useful to quickly calculate the standard value of the potential. An example of the electrochemical series just for a few electrochemical half-reactions taken from [Chapter 10, Table 10.13] is given in Table 4.1. 

Selected Standard Electrode Potentials in Alphabetical Order and the Order from the Most Positive in the Top to the Most Negative in the Bottom for Demonstrating So-Called Electrochemical Series... 

Step 4 Calculate the standard electrode potential, E , for each electrode from the standard Gibbs energy of reaction or find E in the electrochemical series. Using [Chapter 10, Table 10.13 or Table 4.1], the standard electrode potentials are obtained ... 

The standard electrode potential can be calculated using either thermodynamic data or found in a table of standard electrode potentials, so-called electrochemical series. The tabulated standard electrode potentials are available only at a temperature of 25°C and a pressure of 1.013 bar (not 1 bar). 

The electrochemical series (table of the standard electrode potentials) can be very useful for a quick calculation at 25°C. However, if the electrochemical calculations are supposed to be carried out at elevated temperatures, thermodynamic properties of chemicals of the electrochemical reaction should be used. 

The standard electrode potentials in CRC Handbook (Electrochemical Series) are given at... 

Electrical units 503, 519 Electrification due to wiping 77 Electro-analysis see Electrolysis and Electrogravimetry Electrochemical series 63 Electro-deposition completeness of, 507 Electrode potentials 60 change of during titration, 360 Nernst equation of, 60 reversible, 63 standard 60, (T) 62 Electrode reactions 505 Electrodeless discharge lamps 790 Electrodes antimony, 555 auxiliary, 538, 545 bimetallic, 575... 

Each metal or metal area will develop an electrode with a measurable electrical potential. This potential can be referenced to that of a standard hydrogen electrode, which by convention is set at zero. Thus, all metals have either a higher or lower potential compared to hydrogen, and a comparative list of metals can be produced indicating their relative nobility. This list is the galvanic or electrochemical series and measured as an electromotive force (EMF). 

The electrochemical series corresponds only to the standard condition, i.e., for unit activity of the ions, since a change to another ionic concentration can alter the order of the electrode potentials of the elements very markedly. The case of nickel plating mentioned earlier may be taken as typically illustrative of the many practical examples of the effects and the consequences of nonstandard conditions. It must also be mentioned in the context of the examples of displacement reactions provided earlier that the concentrations and the electrode potentials frequently vary during a displacement reaction. 

The redox potentials against the standard hydrogen electrode (SHE) for various reactions, usually called electrochemical series , are listed in the annually updated CRC Handbook of Chemistry and Physics, CRC Press Boca Raton, EL. On the other hand, unless otherwise indicated, the potential values used in this review are all referred to the Li+/Li reference electrode. 

The two cathodic partner reactions in corrosion are hydrogen evolution and oxygen reduction. Consider the Electrochemical Series (for a full list, see The Handbook of Chemistry and Physics) and work out a rule that gives the standard reversible electrode potential, less negative than which (pH 7 and aMzt = lO 6 M) a metal will no longer have a tendency to corrode (a) in 1 M acid and (b) in 1 M alkali. (Bockris)... 

While the redox titration method is potentiometric, the spectroelectrochemistry method is potentiostatic [99]. In this method, the protein solution is introduced into an optically transparent thin layer electrochemical cell. The potential of the transparent electrode is held constant until the ratio of the oxidized to reduced forms of the protein attains equilibrium, according to the Nemst equation. The oxidation-reduction state of the protein is determined by directly measuring the spectra through the tranparent electrode. In this method, as in the redox titration method, the spectral characterization of redox species is required. A series of potentials are sequentially potentiostated so that different oxidized/reduced ratios are obtained. The data is then adjusted to the Nemst equation in order to calculate the standard redox potential of the proteic species. Errors in redox potentials estimated with this method may be in the order of 3 mV. 

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