Ozone oxidizing power

Nickel peroxide is a solid, insoluble oxidant prepared by reaction of nickel (II) salts with hypochlorite or ozone in aqueous alkaline solution. This reagent when used in nonpolar medium is similar to, but more reactive than, activated manganese dioxide in selectively oxidizing allylic or acetylenic alcohols. It also reacts rapidly with amines, phenols, hydrazones and sulfides so that selective oxidation of allylic alcohols in the presence of these functionalities may not be possible. In basic media the oxidizing power of nickel peroxide is increased and saturated primary alcohols can be oxidized directly to carboxylic acids. In the presence of ammonia at —20°, primary allylic alcohols give amides while at elevated temperatures nitriles are formed. At elevated temperatures efficient cleavage of a-glycols, a-ketols... 

The production of ozone in power-plant plumes has been suggested to explain ozone spatial distributions in nonurban areas.Comparison of oxidation mechanisms competing for sulfur dioxide suggests that three reactions—... 

Ozone is an extremely powerful oxidizing agent. In fact, of the common oxidizing agents, only F2 is more potent. A standard method for detecting ozone in polluted air is to pass the air through a basic solution of potassium iodide that contains a starch indicator. The ozone oxidizes iodide ion to iodine, I2, which combines with the starch to give the deep blue starch-iodine complex ... 

For chemical structures refractory to direct reactions with ozone and UV photolysis, free radical reactions are fundamental. Among free radicals, the hydroxyl radical shows a high oxidizing power, and it is generally accepted as the main oxidant in these advanced oxidation systems. 

The reaction shown in Eq. (99) is fast, with a bimolecular rate constant of 3.6xl010 L mol 1 s, and the product is the ozonide anion. Ozonation has an additional benefit. Ozonide decomposes [shown in Eqs. (100) and (101)] to hydroxyl radical and oxygen [56], increasing the oxidative power of the solution by a second mechanism ... 

In acid solution 03 is exceeded in oxidizing power only by fluorine, the perxenate ion, atomic oxygen, OH radicals, and a few other such species. The rate of decomposition of ozone drops sharply in alkaline solutions, the half-life being 2 min in 1 M NaOH at 25°C, 40 min at 5 M, and 83 h at 20 M ... 

What uses of ozone are based upon its oxidizing power Write balanced equations for the formation of nitrogen by (a) the oxidation of ammonia by hot copper oxide (b) the reaction of ammonium ion, NH.j +, and nitrite ion, N02 . ... 

Many of the classic partitioning processes rely on the formation of Am" to facilitate separation from trivalent lanthanides or heavier trivalent actinides. Americium(VI) can be prepared in basic aqueous solutions from Am using powerful oxidants, such as peroxydisulfate, and from Am using weaker oxidants, such as Ce. It can be precipitated from solution as a carbonate by electrolytic or ozone oxidation of concentrated carbonate solutions of Am or Am, or solubilized by dissolution of sodium americyl(VI) acetate. These oxidations and the resulting coordination compounds have been used for relatively large scale processing. For examples, Stephanou et found that Cm could be separated from Am by oxidizing the latter to Am with... 

Since the presence (in very small quantities) of O D) in the troposphere results from the photolysis of ozone (see Reaction (5.16)), an assessment of the oxidizing power of the atmosphere requires that the global budget of tropospheric ozone be accurately quantified. 

Ozone is a very powerful oxidizing agent—its oxidizing power is exceeded only by that of molecular fluorine (see Table 19.1). For example, ozone can oxidize sulfides of many metals to the corresponding sulfates ... 

The oxidizing power of the atmosphere has likely decreased significantly, especially in the Northern Hemisphere, as a result of human activities. As a result, the lifetime of methane may have increased by 10-15% since the preindustrial era. At the same time, the abundance of tropospheric ozone has increased perhaps by as much as a factor of 2-3 in the Northern Hemisphere. Enhanced biomass burning fluxes of NO CO, and hydrocarbons from tropical ecosystems are likely to be important. Future changes in tropospheric ozone are predicted to be largest in the tropics (India, China). These projected increases in tropical emissions are likely to have a... 

Ozone is the second most powerful oxidant molecule, exceeded in it s oxidizing power only by fluorine. Since ozone is a non-polluting oxidant (ozone is... 

It is perhaps helpful at this stage to look at the reactions which free iron ions catalyze. This is chemistry which was originally developed by Fenton in 1894 in order to improve the oxidizing power of hydrogen peroxide by the production of hydroxyl radicals, OH , which have a standard electrode potential of 2.8 V which is more positive than those of ozone, hydrogen peroxide itself (1.8 V) potassium permanganate and chlorine and only marginally less than the standard reduc-... 

Ozone is an important component of the upper atmosphere, where it screens out ultraviolet radiation and so protects us from the effects of these high-energy rays. For this reason, depletion of stratospheric ozone is a major scientific concern, -xc (Section 18.2) In the lower atmosphere, ozone is considered an air pollutant and is a major constituent of smog. <3 (Section 18.2) Because of its oxidizing power, ozone damages living systems and structural materials, especially rubber. 

Ozone is a stronger oxidizing agent tlian dioxygen. One measure of fhis oxidizing power is Ihe high sfandard reduction potential of O3, compared to fhat of O2 -... 

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