RT other T1 Spectrophotometric determination of nitrite in sea water with employment of the standard additions method. Interactive laboratory exercise. A1 Milla González, Miguel A2 Química Analítica K1 quantitative analysis K1 spectrophotometric methods K1 spectrophotometry K1 nitrite K1 nitrite determination K1 spectrophotometric determination of nitrite K1 difenilamine K1 N (1-naphthyl) ethylenediamine dihydrochloride K1 standard additions method K1 SAM K1 simulated lab exercise K1 interactive chemistry K1 analysis of sea water K1 nitrite in sea water AB In this exercise, the determination of nitrite in sea water by visible spectrophotometry is carried out. The nitrite anion reacts in acidic medium with sulfanilamide with formation of a diazonium salt, which, in turn, by a coupling reaction with N (1-naphthyl) ethylenediamine dihydrochloride, gives a red azo compound. This azo derivative absorbs at 540 nm. The steps of the analytical procedure are described and the standard additions method (SAM) is employed to find the nitrite concentration in the sample. The data are randomly generated, and the result of the analysis, expressed in ppb of N-NO2-and must be calculated from the equation of the SAM graph, adjusted by least squares. The exercise is a simulation that helps to understand the protocol of analysis and to carry out the procedure in the laboratory session more efficiently. YR 2014 FD 2014-07-23T00:00:00Z LK http://hdl.handle.net/10498/16572 UL http://hdl.handle.net/10498/16572 LA eng DS Repositorio Institucional de la Universidad de Cádiz RD 23-sep-2023