Flow-injection determination of inorganic forms of nitrogen by gas diffusion and conductimetry

摘要: Abstract A flow-injection—conductimetric method was applied to the determination of ammonia, nitrate and nitrite at concentrations down 5, 20 ng ml −1 , respectively. Ammonia determined by merging injected sample with an alkaline solution (NaOHEDTA) passing mixture through a diffusion cell. The ammonia released collected flowing stream deionized water that passed conductance flow Nitrate were after reduction in medium using column filled metallic zinc. produced then measured as described above. About 60 samples per hour can be processed relative standard deviation about 1%. Satisfactory agreement observed between results for natural tap mineral proposed spectrophotometric procedures. Speciation achieved adding sulphanilic acid remove from determining without use column.