Oxidation thermodynamics

The oxidizing power of the halate ions in aqueous solution, as measured by their standard reduction potentials (p. 854), decreases in the sequence bromate > chlorate > iodate but the rates of reaction follow the sequence iodate > bromate > chlorate. In addition, both the thermodynamic oxidizing power and the rate of reaction depend markedly on the hydrogen-ion concentration of the solution, being substantially greater in acid than in alkaline conditions (p, 855). 

Fig. 4. Catalytic activities of metals (as potentials measured at 10-4 A.cm-2) for anodic oxidation of different reductants. Er thermodynamic oxidation-reduction potentials of reductants. H2 reversible hydrogen electrode potential in solution used to study oxidation of each reductant. Adapted from ref. 38.

Uppsala and Northwestern University, thermodynamic calculations were performed using Bi(ph)3, Sr(hfa)itet, Ca(hfa)2tet, and Cu(acac)2 as metal-organic precursors [126]. The experimentally observed phase stability of BSCCO for in situ CVD was in agreement with the calculated thermodynamic oxide stability diagrams [126]. These results indicate that thermodynamic modeling can be used as a guide for the optimization of CVD routes to complex metal oxide films. 

Thermodynamic Oxidation-Reduction Free Energy Heat Content Entropy... 

Zhang, X. R. Pugh, J. K. Ross, P. N., Computation of Thermodynamic Oxidation Potentials of Organic Solvents Using Density Functional Theory. J. Electrochem. Soc. 2001, 148, E183-E188. 

Zhang XR, Pugh JK, Ross PN (2001) Compulation of thermodynamic oxidation potentials of organic solvents using density functional theory. J Electrochem Soc 148 E183... 

The solid phase analyses by QXRD show that the main phase in the residues is magnetite. Also, magnetite concentration increases with temperature. Thermodynamically, oxide formation is favored by temperature [14]. Magnetite formation could explain the low recoveries and losses of cobalt and manganese. There are numerous studies showing that cobalt can co-precipitate with iron and/or manganese oxides because it can replace these cations in the spinel, and that this phenomenon is favored by increased temperatures [7, 18]. 

The corresponding quantities in solution are Eqx° (D) and Ered° (A), the thermodynamic oxidation and reduction potentials of the donor and acceptor, respectively. 

Chen, S. and L.-W. Wang, Thermodynamic oxidation and reduction potentials of photocatalytic semiconductors in aqueous solution. arXiv.org, e-Print Arch., Condens. Matter, 2012 p. 1-5, arXiv 1203.1970vl [cond-mat.mtrl-sci]. 

The chemistiy of fused systems is, of course, mainly concerned with those liquids containing at least two components. For the present some of the factors which appear important with regard to chemical properties and reactions in molten salts will be considered in a general manner. Specific examples of the behavior of salt mixtures in electrochemical, kinetic, spectroscopic, thermodynamic, oxidation-reduction, synthetic, and other studies will be presented in the following sections. 

Chen SY, Wang LW (2012) Thermodynamic oxidation and reduction potentials of photocatalytic scanicmiductras in aqueous solutimi. Chem Mater 24 3659-3666... 

Olefin synthesis starts usually from carbonyl compounds and carbanions with relatively electropositive, redox-active substituents mostly containing phosphorus, sulfur, or silicon. The carbanions add to the carbonyl group and the oxy anion attacks the oxidizable atom Y in-tramolecularly. The oxide Y—O" is then eliminated and a new C—C bond is formed. Such reactions take place because the formation of a Y—0 bond is thermodynamically favored and because Y is able to expand its coordination sphere and to raise its oxidation number. 

Latimer, 1952). Therefore all applied oxidants are, in thermodynamic terms, able to oxidize or to dehydrogenate all hydrocarbons and all oxidizable functional groups of organic molecules. 

Unlike the reactions that we have already considered, the equilibrium position of a redox reaction is rarely expressed by an equilibrium constant. Since redox reactions involve the transfer of electrons from a reducing agent to an oxidizing agent, it is convenient to consider the thermodynamics of the reaction in terms of the electron. 

Solutions of Mn04 are prepared from KMn04, which is not available as a primary standard. Aqueous solutions of permanganate are thermodynamically unstable due to its ability to oxidize water. 

The red precipitates of AgF are diamagnetic and isostmctural with AuF. Silver trifluoride is a powerful oxidizing agent and thermodynamically unstable. 

Table 1. Physical and Thermodynamic Properties of Helium-Group Gas Fluorides, Oxofluorides, and Oxides...

Halides. Xenon duorides, xenon oxide tetraduoride [13774-85-1XeOE, and their complexes are the only thermodynamically stable xenon compounds. Xenon diduo ride [13709-36-9] xenon tetraduoride [13709-61-0], and xenon hexaduoride [13693-09-9] are colodess, crystalline soHds which can be sublimed under vacuum at 25°C. The mean thermochemical bond energies are XeE2, 132.3 0.7 kJ/mol (31.6 0.2 kcal/mol) XeE ... 

Oxides. Two oxides of xenon are known xenon trioxide [13776-58-4], XeO, and xenon tetroxide [12340-14-6], XeO (Table 1). Xenon trioxide is most efftcientiy prepared by the hydrolysis of XeE (47) or by the reaction of XeE with HOPOE2 (48). The XeO molecule has a trigonal pyramidal shape Xe—O, 176(3) pm (49), and XeO is tetrahedral with Xe—O, 173.6(2) pm (50). Xenon tetroxide is prepared by the interaction of concentrated sulfuric acid with sodium or barium perxenate, Na XeO, Ba2XeO ( )- Both oxides are thermodynamically unstable, explosive soHds which must be... 

Electron Transport Between Photosystem I and Photosystem II Inhibitors. The interaction between PSI and PSII reaction centers (Fig. 1) depends on the thermodynamically favored transfer of electrons from low redox potential carriers to carriers of higher redox potential. This process serves to communicate reducing equivalents between the two photosystem complexes. Photosynthetic and respiratory membranes of both eukaryotes and prokaryotes contain stmctures that serve to oxidize low potential quinols while reducing high potential metaHoproteins (40). In plant thylakoid membranes, this complex is usually referred to as the cytochrome b /f complex, or plastoquinolplastocyanin oxidoreductase, which oxidizes plastoquinol reduced in PSII and reduces plastocyanin oxidized in PSI (25,41). Some diphenyl ethers, eg, 2,4-dinitrophenyl 2 -iodo-3 -methyl-4 -nitro-6 -isopropylphenyl ether [69311-70-2] (DNP-INT), and the quinone analogues,... 

Long-chain primary alcohols, eg, triacontanol, can be prepared by the hydroboration, isomerization, and oxidation of the corresponding internal alkenes (437). The less thermodynamically stable stereoisomer can be transformed into the more stable one by heating, eg, i j -into /ra/ j -myrtanjiborane (204). 

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