Reduction potentials general table

Values of AjG,aq) and A,G oin) for several radical species have been given in Table 8. Generally the AfG(aq were obtained from the reduction potentials in Tables 6 and 7 and A, G,aq of the products of reduction half reactions. The A, G,aq) of sulfur species were calculated from A, G(g/ s in Wagman et al. [5] and Stein et al. [10], and solution free energies [87]. In cases where ions were generated as well as the sulfur parent species, for example reaction (41) ... 

In general, reduction potentials of nucleobases have been studied much less than their oxidation potentials, and in particular water-based data are rather lacking [2, 35]. We therefore listed the available polarographic potentials measured in dimethylformamide and data obtained from pulse radiolysis studies or fluorescence quenching measurements. From the data in Table 1, it is evident that the pyrimidine bases are most easily reduced. The reduction potential of the T=T CPD lesion is close to the estimated value of the undamaged thymine base [34, 36]. 

If the free element is less active than the corresponding element in the compound, no reaction will take place. A short list of metals in order of their reactivities and an even shorter list of nonmetals are presented in Table 7-1. The metals in the list range from very active to very stable the nonmetals listed range from very active to fairly active. A more comprehensive list, a table of standard reduction potentials, is presented in general chemistry textbooks. 

Some lines of prokaryote development are shown in Table 6.2 with a guide to oxidation/reduction potential ranges in Table 6.3. In all these and further changes the novel chemistry has to be built into the cooperative whole (see Section 3.9). Note again the necessity that the novel features must become part of a controlled autocatalytic restricted set of reaction paths, which become general to any further evolution. 

Although the same limitations apply to the use of F as those described above for the anodic counterpart, the global trend in Fig. 7 shows that gas-phase electron affinities also generally reflect the trend in the reduction potentials measured in solution for the large variety of (uncharged) acceptor structures included in Table 4.71... 

Type II copper enzymes generally have more positive reduction potentials, weaker electronic absorption signals, and larger EPR hyperfine coupling constants. They adopt trigonal, square-planar, five-coordinate, or tetragonally distorted octahedral geometries. Usually, type II copper enzymes are involved in catalytic oxidations of substrate molecules and may be found in combination with both Type I and Type III copper centers. Laccase and ascorbate oxidase are typical examples. Information on these enzymes is found in Tables 5.1, 5.2, and 5.3. Superoxide dismutase, discussed in more detail below, contains a lone Type II copper center in each of two subunits of its quaternary structure. 

In general, an electrode with a lower electrode potential in Table 5.1 will reduce the ions of an electrode with a higher electrode potential (Fig. 5.10) or, a high positive standard electrode potential indicates a strong tendency toward reduction, whereas a low negative standard electrode potential indicates a strong tendency toward the... 

Practically in every general chemistry textbook, one can find a table presenting the Standard (Reduction) Potentials in aqueous solution at 25 °C, sometimes in two parts, indicating the reaction condition acidic solution and basic solution. In most cases, there is another table titled Standard Chemical Thermodynamic Properties (or Selected Thermodynamic Values). The former table is referred to in a chapter devoted to Electrochemistry (or Oxidation - Reduction Reactions), while a reference to the latter one can be found in a chapter dealing with Chemical Thermodynamics (or Chemical Equilibria). It is seldom indicated that the two types of tables contain redundant information since the standard potential values of a cell reaction ( n) can be calculated from the standard molar free (Gibbs) energy change (AG" for the same reaction with a simple relationship... 

Purines. In general, -OH readily adds to double bonds but undergoes ET reactions only very reluctantly (Chap. 3.2). This also applies to purines despite their relatively low reduction potentials (Table 10.2). Thus, G- which is formed in the reaction of OH with dGuo has a short-lived -OH-adduct rather than G-+ as precursor (Candeias and Steenken 2000), and the H-abstraction that could also lead to G (for theoretical calculations see Mundy et al. 2002) does not occur to any significant extent. 

CONCLUSIONS DRAWN FROM THE TABLES OF OXIDATION-REDUCTION POTENTIALS From the values of oxidation-reduction potentials we can easily find out whether a particular oxidation-reduction reaction is feasible or not. We have already seen the rules that govern the displacement of metals by one another, and the feasibility of dissolving metals in acid with the liberation of hydrogen. Those conclusions can now be extended and generalized. It can be said that the more positive the oxidation-reduction... 

Since the potentials in Table XLIX give the free energies of the oxidation reactions, using the term oxidation in its most general sense, they may be called oxidation potentials the potentials for the reverse processes, i.e., with the signs reversed, are then reduction potentials (cf. p. 435). 

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