METHOD OF DETERMINING SODIUM THIOSULPHATE IN SOLUTIONS

摘要

FIELD: chemistry.;SUBSTANCE: invention relates to analytical chemistry and can be used in a system for monitoring content of sodium thiosulphate in solutions. The method of determining sodium thiosulphate in solutions is characterised by adding an analysed sample into a reaction vessel containing a corresponding amount of photogenerated iodine, obtained by blowing with air for 1-2 minutes and irradiating the reaction mixture with a stabilised light source, the mixture consisting of 0.5 M potassium iodide solution, an acetate buffer solution with pH 5.6 and a sodium eosinate sensitising agent, by detecting change in current in a cell and upon achieving constant current, re-blowing the reaction mixture with air for 2-3 minutes and re-irradiating with the stabilised light source until achieving the initial amount of iodine in the vessel, measuring the iodine generation time spent on achieving the decrease thereof, determining the amount of sodium thiosulphate from a calibration curve from the change in current and generation time.;EFFECT: invention provides a simple method of determining sodium thiosulphate in solutions and avoids use of expensive equipment.;10 tbl, 5 dwg