Exchange reactions of oxygen

In marked contrast, AS of the exchange reaction of oxygen in a six-coordinated complex, trans-[Re02(py)4] + is negative, ( - 32 JKT1 mol-1), suggesting that the reaction proceeds by a dissociative mechanism. This is also supported by the kinetic analysis of the exchange reaction of pyridine on trans-[M02(py)4]+ (M = Tc or Re), which was monitored by H-NMR [15] ... 

Isotope-exchange reactions of oxygen on oxides have been reviewed by Novakova (387) and this section is restricted to those papers containing spectroscopic information about the adsorbed oxygen species. In general, there is very little direct evidence in the literature on the type of surface complexes involved in the exchange. 

Isotopic exchange reactions of oxygen have been studied ever since water enriched in the stable isotopes of oxygen (O18 and O17) became available in the 1930 s (Lewis and Cornish, 1933 Urey et al., 1936). 

Doomkamp C, Clement M, Ponec V (1999) The isotopic exchange reaction of oxygen on metal oxides. J Catalysis 182 390-399... 

In this subsection the decomposition of N2O and NO to N2 and O2 and the oxidation of NO to NO2 will be considered. All three reactions are catalyzed to various extents on rare earth oxides above 350°C, and they follow a common activity pattern, which is that of the isotopic exchange reaction of oxygen. As the molecular desorption of oxygen occurs in both decomposition reactions, it is suggested that the associative desorption of oxygen plays a major role in the rate-limiting processes. 

KJier, K., Novakova, I, Jiru, P. (1963) Exchange reactions of oxygen between oxygen molecules and soUd oxides. /. Catal,2,4,19. 

Oxygen-exchange reactions of square-pyramidal metal(V) complexes have been reported [14]. In monooxotechnetium(V) and monooxorhenium(V) complexes with N,iV -bis(mercaptoaeetyl)butane-l,4-diamine(DBDS), the exchange of oxygen between the complexes and water in DMSO medium ... 

Oxyacids of sulphur and their anhydrides, mechanisms and reactivity in reactions of organic, 17, 65 Oxygen isotope exchange reactions of organic compounds, 3, 123... 

Oxygen isotope exchange reactions of organic compounds, 3, 123... 

The oxygen atoms in the silicalite framework can be classified into approximately three kinds by the isotope exchange method proposed by Endoh et al. [12]. On the exchange reaction of in the zeolite framework with C 02 in the gas phase at 773 K, the most reactive oxygen atoms were in the terminal SiOH... 

That is, the 0/ 0 ratio in a sample is compared with a standard, and the difference is expressed as per mil (per thousand). The standard for oxygen isotopes is standard mean ocean water (SMOW). The exchange reaction of 0 and O between two minerals is a heterogeneous reaction and may be written as, e.g.. 

Catalysts and their effects on chemical reactions aid in efficiency, effectiveness and selectivity. A recent example of current research is redox and ligand exchange reactions of the oxygenation catalyst (N,N -bis(salicylidene)ethylenediaminato)co-balt(II), Co(SALEN)2 (below), and its one-electron oxidation product, Co(salen) 2-These were investigated in DMF, pyridine, and mixtures of these solvents. Solvent effects on the potentials, the thermodynamics of cross reactions, and the distribution of Co(II) and Co(III) species as a function of the solvent composition are important considerations (Eichhorn, 1997). The results in these solvents should be compared with other work with catalysts using more environmentally benign media (Collins et al., 1998). 

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