Adsorption-bonded azo reagents in chemical tests based on the principles of precipitation paper chromatography

The possibility of using three groups of azo compounds in chemical tests based on the principles of precipitation paper chromatography is considered. Test procedures have been developed for the determination of acids, alkalis (0.1-100 mM), the total alkalinity of water (0.2-35 mM), the total acidity of water (0.2020 mM), Cd and Pb (1-200 mg/L), Al, Th, U, and Zr (0.5-200 mg/L), and the total hardness of water (0.05-40 mM). The length of the colored zone of test strips laminated into a polymer film and contacting with the test solution through a narrow edge is the analytical signal. The relative standard deviation does not exceed 0.3; the analysis time is 10-15 min