Abstract
A rapid, simple, sensitive and selective spectrophotometric determination of trace nitrite is described. The method is based on a diazotization-coupling reaction between dapsone and N-(1-naphthyl)ethylenediamine dihydrochloride (NEDA) in a hydrochloric acid medium. The molar absorptivity and Sandell's sensitivity were found to be 7.2 × 104 1 mol−1 cm−1 and 0.00063 μg ml−1, respectively. The calibration graph is linear for 0.002–0.6 μg ml−1 of nitrite. The interference effects of various cations and anions were also studied and reported. This method has been found to be applicable to the determination of nitrite in various water samples.