On the possibility of a pH-metric determination of ozone

A novel approach for the detection and determination of ozone is presented. The method is based on monitoring the pH increase due to the reaction of ozone with an unbuffered solution of KI, during which hydroxyl ions are produced. Based on theoretical calculations, a pH increase of 0.01 pH-units corresponds to 2.3 × 10−9 M of reacting concentration of ozone, when the initial pH of the KI solution is 7.00. Deviations from the ideal neutrality due to the presence of traces of acidic or basic impurities can be taken into account. A comparison between the expected pH changes and those experimentally achieved for given amounts of ozone has been made.