Redox inorganic

We kindly acknowledge financial support from the Deutsche Forschungsgemeinschaft (SFB 583) and a grant from the University of Erlangen-Nuremberg (Emerging Field Initiative Medicinal Redox Inorganic Chemistry). 

Several reasons might be put forward in order to explain the boom of photoinduced redox inorganic chemistry. Two important factors are the following ... 

The standard redox potentials of inorganic oxidants used in organic synthesis are generally around or above + 1.0 V. Organic substrates do not have such high potentials. The values for the CH4/CH3OH and CjHj/CjHjOH couples are at +0,59 V and 0.52 V, respectively. The oxidation of alcohols and aldehydes corresponds to values around 0.0 V (W.M. 

Inorganic Analysis Redox titrimetry has been used for the analysis of a wide range of inorganic analytes. Although many of these methods have been replaced by newer methods, a few continue to be listed as standard methods of analysis. In this section we consider the application of redox titrimetry to several important environmental, public health, and industrial analyses. Other examples can be found in the suggested readings listed at the end of this chapter. 

Another important example of redox titrimetry that finds applications in both public health and environmental analyses is the determination of dissolved oxygen. In natural waters the level of dissolved O2 is important for two reasons it is the most readily available oxidant for the biological oxidation of inorganic and organic pollutants and it is necessary for the support of aquatic life. In wastewater treatment plants, the control of dissolved O2 is essential for the aerobic oxidation of waste materials. If the level of dissolved O2 falls below a critical value, aerobic bacteria are replaced by anaerobic bacteria, and the oxidation of organic waste produces undesirable gases such as CH4 and H2S. 

Another important example of a redox titration for inorganic analytes, which is important in industrial labs, is the determination of water in nonaqueous solvents. The titrant for this analysis is known as the Karl Fischer reagent and consists of a mixture of iodine, sulfur dioxide, pyridine, and methanol. The concentration of pyridine is sufficiently large so that b and SO2 are complexed with the pyridine (py) as py b and py SO2. When added to a sample containing water, b is reduced to U, and SO2 is oxidized to SO3. 

The amount of Cr + in inorganic salts can be determined by a redox titration. A portion of sample containing... 

In redox initiation, the free radicals that initiate the polymerization are generated as transient intermediates in the course of redox reaction. Essentially this involves an electron transfer process followed by scission to give free radicals. A wide variety of redox reactions, involving both organic and inorganic components either wholly... 

The abbreviations for the investigation methods are also taken from the nomenclature of Sillen and Martel 1 (76) aiex = anion exchange cal = calorimetry ciex = cation exchange dis = distribution between two phases est = estimate red = e.m.f. with redox electrode sp = spectrophotometry. Our selected data, rather limited in number, arise from the present status of the IAEA assessment of inorganic complexes of the actinides (12). 

They present a large and reverse redox potential range, in contrast to the well-defined narrow peaks of the inorganic or organic redox couples... 

NMR studies on graphite-phosphoric acid showed simultaneous, motional narrowing of both H and resonances above 225 K, indicating high mobility of phosphoric acid in the compound (FS). Chloro-sulfonic acid is inserted alone into graphite in the presence of many inorganic chlorides. The reaction temperature and stage seem to be related to the redox potential of the M"+-M couple (M3). 

The latter reaction must involve a large number of molecular steps and may be a much slower process. The mechanisms of a few inorganic electron transfer processes have been summarized by Taube (1968). The presence of very slow reactions when several redox couples are possible means that the Eh value measured with an instrument may not be related in a simple way to the concentrations of species present, and different redox couples may not be in equilibrium with one another. Lindberg and Runnells (1984) have presented data on the extent of disequilibrium... 

Abstract Inorganic polysulfide anions and the related radical anions S play an important role in the redox reactions of elemental sulfur and therefore also in the geobio chemical sulfur cycle. This chapter describes the preparation of the solid polysulfides with up to eight sulfur atoms and univalent cations, as well as their solid state structures, vibrational spectra and their behavior in aqueous and non-aqueous solutions. In addition, the highly colored and reactive radical anions S with n = 2, 3, and 6 are discussed, some of which exist in equilibrium with the corresponding diamagnetic dianions. 

Seven chemical reactions were identified from the chemistry syllabus. These chemical reactions were selected because they were frequently encountered during the 2-year chemistiy course and based on their importance in understanding concepts associated with three topics, namely, acids, bases and salts, metal reactivity series and inorganic chemistry qualitative analysis. The seven types of chemical reactions were combustion of reactive metals in air, chemical reactions between dilute acids and reactive metals, neutralisation reactions between strong acids and strong alkalis, neutralisation reactions between dilute acids and metal oxides, chemical reactions between dilute acids and metal carbonates, ionic precipitation reactions and metal ion displacement reactions. Although two of the chemical reactions involved oxidation and reduction, it was decided not to include the concept of redox in this study as students had only recently been introduced to ion-electron... 

L Her M (2006) Redox Properties, Electrochemistry of Oxygen. In Bard AJ, Stratmann M (eds) Encyclopedia of Electrochemistry, Vol. 7a Inorganic Chemistry, Scholz E, Pickett ChJ (eds), WUey-VCH, Weinheim, p 117... 

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