This method describes how to determine the ozone content of water using iodometric titration.
Ozone oxidizes iodide to iodine, which forms a clathrate compound that exhibits a blue color and which loses its color through titration with a sodium thiosulfate solution. The ozone concentration is determined on the basis of the quantity of sodium thiosulfate solution consumed in the reaction.
The method describes how to determine the ozone content of water photometrically with a cuvette test.
Ozone causes the color of indigo trisulfonate to disappear in a stoichiometric reaction. The decrease in absorbance is measured at a wavelength of 600 nm.