TEST SYSTEMS FOR THE DETERMINATION OF HALIDES

A test method is proposed for determining halides by measuring the len gth of the colored or discolored zone of an indicator paper (30 x 80 m m) glued in a polymeric film so that one end of this paper is in conta ct with the Liquid under study. For fluoride determination, the indica tor paper is impregnated with the zirconium Alizarin complex. To deter mine chlorides, the paper is treated with silver chromate or silver he xacyanoferrate(III). In the determination of bromides and iodides, ind icator papers impregnated with silver chromate, silver hexacyanoferrat es(II, III), or silver chloride are used. The analytical ranges are 0. 2-200 mg/L for fluorides, 0.1-1000 mg/L, for chlorides, and 0.2-1000 m g/L for bromides and iodides. The selectivity of test systems was. Tes t procedures for determining halogenides in environmental samples are proposed. The relative standard deviation does not exceed 36%. The dur ation of analysis is 15-40 min.