Simultaneous ultraviolet spectrophotometric determination of nitrate and nitrite

Spectrophotometric determination of nitrite and nitrate using phosphomolybdenum blue complex.

A method for spectrophotometric determination of nitrite and nitrate is described. This method is based on the reduction of phosphomolybdic acid to phosphomolybdenum blue complex by sodium sulfide. The obtained phosphomolybdenum blue complex is oxidized by the addition of nitrite and this causes a reduction in intensity of the blue color. The absolute decrease in the absorbance of the blue colo...

New Reagents for the Spectrophotometric Determination of Nitrite and Nitrate

Simultaneous spectrophotometric determination of nitrite and nitrate by flow-injection analysis.

An automatic direct spectrophotometric method for the simultaneous determination of nitrite and nitrate by flow-injection analysis has been developed. Nitrite reacts with 3-nitroaniline in the presence of hydrochloric acid (0.96-1.8 M HCl or pH 0.5-0.7) to form a diazonium cation, which is subsequently coupled with N-(1-naphthyl)-ethylenediamine dihydrochloride to form a stable purple azo dye, ...

Spectrophotometric simultaneous determination of nitrite, nitrate and ammonium in soils by flow injection analysis.

A new rapid flow injection procedure for the simultaneous determination of nitrate, nitrite and ammonium in single flow injection analysis system is proposed. The procedure combines on-line reduction of nitrate to nitrite and oxidation of ammonium to nitrite with spectrophotometric detection of nitrite by using the Griess-Ilosvay reaction. The formed azo dye was measured at 543 nm. The influenc...

Nitrate and Nitrite Ultraviolet Actinometers

We developed nitrate and nitrite actinometers to determine radiant fluxes from 290 to 410 nm. These actinometers are based on the reaction of the photochemically generated OH radical with benzoic acid to form salicylic acid (SA) and p-hydroxybenzoic acid (pHBA). Actinometer development included determination of the temperature and wavelength dependence of the quantum yield for formation of SA a...