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|Section2= |Section3= |Section4= |Section5= |Section8= }} Ozone (systematically named 1λ1,3λ1-trioxidane and ''catena''-trioxygen), or trioxygen, is an inorganic molecule with the chemical formula . It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope , breaking down in the lower atmosphere to normal dioxygen. Ozone is formed from dioxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere (stratosphere). In total, ozone makes up only of the atmosphere. Ozone's odour is sharp, reminiscent of chlorine, and detectable by many people at concentrations of as little as in air. Ozone's O3 formula was determined in 1865. The molecule was later proven to have a bent structure and to be diamagnetic. In standard conditions, ozone is a pale blue gas that condenses at progressively cryogenic temperatures to a dark blue liquid and finally a violet-black solid. Ozone's instability with regard to more common dioxygen is such that both concentrated gas and liquid ozone may decompose explosively. It is therefore used commercially only in low concentrations. Ozone is a powerful oxidant (far more so than dioxygen) and has many industrial and consumer applications related to oxidation. This same high oxidising potential, however, causes ozone to damage mucous and respiratory tissues in animals, and also tissues in plants, above concentrations of about . This makes ozone a potent respiratory hazard and pollutant near ground level. However, the ozone layer (a portion of the stratosphere with a higher concentration of ozone, from two to eight ppm) is beneficial, preventing damaging ultraviolet light from reaching the Earth's surface, to the benefit of both plants and animals. == Nomenclature == The trivial name ''ozone'' is the most commonly used and preferred IUPAC name. The systematic names ''1λ1,3λ1-trioxidane'' and ''catena-trioxygen'', valid IUPAC names, are constructed according to the substitutive and additive nomenclatures, respectively. The name ''ozone'' derives from ''ozein'' (ὄζειν), the Greek word for smell (verb), referring to ozone's distinctive smell. In appropriate contexts, ozone can be viewed as trioxidane with two hydrogen atoms removed, and as such, ''trioxidanylidene'' may be used as a context-specific systematic name, according to substitutive nomenclature. By default, these names pay no regard to the radicality of the ozone molecule. In even more specific context, this can also name the non-radical singlet ground state, whereas the diradical state is named ''trioxidanediyl''. ''Trioxidanediyl'' (or ''ozonide'') is used, non-systematically, to refer to the substituent group (-OOO-). Care should be taken to avoid confusing the name of the group for the context-specific name for ozone given above. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Ozone」の詳細全文を読む スポンサード リンク
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