Oxygen from water

TbF4 (TbF, -f F, at 3(WC) and Cs,Tbp7 are known and Tb oxides intermediate between Tb, , and TbO, are formed by healing Tb compounds in air. These higher oxides liberate oxygen from water. Tb, , and TbCl (TbCl, plus Tb) have metal-metal bonding. 

Hydrated cobalt III) sulphate, Co2(S04)3. JSHjO is obtained when cobalt(II) sulphate is oxidised electrolytically in moderately concentrated sulphuric acid solution it is stable when dry but liberates oxygen from water. Some alums, for example KCo(S04)2.12H,0 can be obtained by crystallisation from sulphuric acid solutions. In these and the sulphate, the cation [CofHjO) ] may exist it is both acidic and strongly oxidising. 

Hydrogen peroxide can be dissociated over a catalyst to produce oxygen, water, and heat. It is an energetic reaction, and contaminants can spontaneously decompose the hydrogen peroxide. Oxygen from water electrolysis is used for life support on submarines. 

Sherwood and Holloway [61] also studied the desorption of oxygen from water. 

Molecular photocatalytic systems for solar energy conversion catalysts for the evolution of hydrogen and oxygen from water. K. I. Zamaraev and V. N. Parman, Russ. Chem. Rev. (Engl. Transl.), 1983,52,817-836(114). 

Self-Test 14.5B Like K02, cesium superoxide, Cs02, can be used to remove exhaled C02 and generate oxygen from water. Explain why K02 is preferred for this purpose on spacecraft. 

Incorporation of Oxygen from Water Oxidoreductases and Hydratases Oxidoreductases... 

Photosynthesis is the reverse of reaction (30.1) the formation of carbohydrates and oxygen from water and carbon dioxide with solar energy. Photosynthesis occurs in the chloroplasts contained in the cells of green plants. The chloroplasts hold two types of photosynthetic systems, which are called PSl and PS 11. These systems... 

Studies of Ag on Au(lll)87 yield very similar results in terms of the structure of the deposited monolayer (i.e., the silver atoms are bonded to three surface gold atoms and are located at three-fold hollow sites forming a commensurate layer) with again strong interaction by oxygen from water or electrolyte (perchlorate). 

Fig. 5.9. A possible structure of the Mn/Ca site for the synthesis of oxygen from water. Other structures have been proposed. The site is not very stable and the whole protein holding the metal ions must be replaced frequently. There is a chloride ion nearby (see Rutherford and Boussac and Biesiaka et al., in Further Reading).

One of the simplest ways of removing gaseous oxygen from water is to bubble nitrogen gas through it (a process called sparging ). 

It has been reported (Calzaferri et al., 1984) that oxygen from water is evolved upon irradiation of a silver-loaded zeolite (a group of alumino-silicates) suspension according to the following overall stoichiometry ... 

A photoredox system for the production of oxygen from water using Ru(bpy)3+ as a sensitiser is shown in Figure 7.16. This system involves oxidative quenching of excited Rufbpy) by the Co(III) complex Co(NH3)5C12+ ... 

Figure 12.9. Fleight of the transfer unit Hz, for stripping of oxygen from water in a spray tower...

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