Multiwavelength spectrophotometric determination of the acidity constant of Nitroso-R-Salt in various micellar media solutions

The investigation of the dissociation equilibrium of Nitroso-R-Salt (NRS) in aqueous micellar solution was determined spectrophotometrically at 25°C and at the constant ionic strength I = 0.1 M KNO₃. For this purpose, the effect of nonionic (Triton X-100), cationic (CTAB), and anionic (SDS) surfactants on the absorption spectra of NRS at different pH values were studied. The acidity constants of all related equilibria are estimated using the whole spectral fitting of the collected data to an established factor analysis model. The computer program DATAN was used to extract the desired information from the spectral data. The outputs of the fitting processes were acidity constant, spectral profiles of pure forms, distribution diagrams and other factor analysis data. The effects of surfactant on acidity constant and pure spectrum of each component are discussed.