Nitrogen compounds nitrites

The comprehensive method determines the nitrogen content for all forms of nitrogen compounds (nitrite, nitrate, urea, organic nitrogen, and ammonia), which upon distillation can be collected in a known amount of sulfuric acid and titrated with sodium hydroxide. A great deal of time is consumed in performing this classical nitrogen method. Note Boric acid may be used for collection of ammonia in the distillation step rather than sulfuric acid. 

The determination of the three nitrogen compounds - nitrite, nitrate, and ammonium - is of special interest in the field of wastewater analysis. Because wastewater samples usually contain a high amount of chloride, nitrite, which elutes immediately after chloride, can be determined unequivocally by means of... 

Nitrous acid or alkyl nitrites react with a number of nitrogen compounds to yield tetrazoles. For example, hydrazidines (87), which can be prepared in situ from the corresponding iminoesters, react with nitrous acid or its derivatives to give 1-substituted tetrazoles (88).150-152 This reaction (Eq. 17), is one of the most extensively used methods for the synthesis of... 

Ultraviolet photo-oxidation techniques can be used as a method for organic nitrogen. The organic nitrogen compounds are oxidised to nitrate and nitrite then determined by the standard seawater analysis methods [17,18,23]. 

Nitrogen species, such as nitrate and nitrite, are known to be confirmed procarcinogens. The excessive input of these nitrogen compounds with food and drinking water in the presence of tertiary amines, for instance, from medicines, can lead to the formation of carcinogenic N-nitrosoamines. 

A. Analysis of Wastewater and Natural Waters. The presence of certain anions in wastewater effluents can cause deterioration of natural water systems. Phosphorous and nitrogen can be present in several chemical forms in wastewaters. Phosphorous is usually present as phosphate, polyphosphate and organically-bound phosphorus. The nitrogen compounds of interest in wastewater characterization are ammonia, nitrite, nitrate and organic nitrogen. Analyses are often based on titrimetric, and colorimetric methods (3). These methods are time consuming and subject to a number of interferences. Ion Chromatography can be used to determine low ppm concentrations of these ions in less than thirty minutes with no sample preparation. 

The role of the various crystal faces in the reduction of nitrite, nitrate, and other oxygen-containing nitrogen compounds has been studied recently [231, 232]. 

As is indicated in Fig. 24-1, the interconversions of nitrate and nitrite with ammonia and with organic nitrogen compounds are active biological processes. Two genera of nitrifying soil bacteria, which are discussed in Chapter 18, oxidize ammonium ions to nitrate. Nitrosomas carries out the six-electron oxidation to nitrite (Eq. 18-17) and Nitrobacter the two-electron oxidation of nitrite to nitrate (Eq. 18-18).79... 

Several of these cytochromes use nitrogen compounds as electron acceptors. Cytochrome cdx from Pseudomonas aeruginosa is a greenish-brown soluble enzyme which contains one c and one chlorin dx) heme in each of two subunits of 63 000 molecular weight. The presence of four redox centres is appropriate for the efficient catalysis of the four-electron reduction of dioxygen to water. It appears, however, that its physiological role may be the reduction of nitrite to NO. Kinetic studies on the anaerobic reduction of cd, by Fe(EDTA)2- have focused attention on electron transfer between the heme groups in the enzyme.722... 

Amidosulfuric acid (Sulfamic acid) [5329-14-6] H 0 N ", H h fro O HCS 1980, 869 Chlorine See Chlorine Nitrogen compounds (reference 7) Metal nitrates or nitrites See METAL AMIDOSIJLFATES See other INORGANIC ACIDS, N—S COMPOUNDS h3no3s... 

Below the photic layer the nitrate concentrations start to increase, from the depth where nitrite and ammonia maxima are usually observed. In the regions affected by the coastal influx concentrations of inorganic nitrogen, compounds are larger and they may suddenly increase during the rains [45]. 

Nitrogen compounds are also usually present in rain water in the form of ammonia, nitrites, and nitrates, the two latter particularly during and after a thunderstorm owing to the combination of oxygen and nitrogen induced by the lightning and electric disturbances generally. 

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