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DictionarySeenitriteNitrites
Nitrites salts of nitrous acid, HNO2. Nitrites are colorless, crystalline compounds that are thermally less stable than nitrates. The nature of decomposition depends on the cation. For example, 2Ba(NO2)2 = BaO + Ba(NO3)2 + NO2 + ½N2, whereas 2AgNO2 = AgNO3 + Ag + NO. Almost all nitrites are highly soluble in water (an exception is AgNO2). Nitrites may have both oxidizing and reducing properties. Nitrites are obtained by the action of a mixture of NO and NO2 on oxides and hydroxides, by the reduction of nitrates, and by exchange reactions. They are used mainly in the production of azo dyes. (The most important nitrites are described in separate articles—see, for example, SODIUM NITRITE.) nitrites
nitrites Chemistry
A family of chemically stable forms of inorganic nitrogen that are not present in significant amounts in the environment. Nitrites in the blood originate from bacterial conversion of nitrates present in vegetables, as well as from nitrites ingested as preservatives (e.g., sodium nitrite, used as a preservative for fish and meats, such as hot dogs, bacon, corned beef, ham, liverwurst or salami), which have been associated with allergic reactions and formation of methaemoglobin. Nitrites are potentially toxic, given their conversion to carcinogenic nitrosamines.
Lab medicine
The reduction products of nitrates by bacteria in urine. In a standard dipstick test, nitrites combine with sulfanilamide on the dipstick, resulting in diazonium salt formation which, in the presence of a dye on the dipstick, forms a coloured azo dye. |