The amount of ozone, O₃, in a mixture of gases can be determined by passing the mixture through a solution of excess potassium iodide, KI. Ozone reacts with the iodide ion as follows:

The amount of I₃^- produced is determined by titrating with thiosulfate ion, S₂O₃^2-:

A mixture of gases occupies a volume of 53.2 L at 18 °C and 0.993 atm. The mixture is passed slowly through a solution containing an excess of KI to ensure that all the ozone reacts. The resulting solution requires 26.2 mL of 0.1359 M Na₂S₂O₃ to titrate to the end point. Calculate the mole fraction of ozone in the original mixture.

Transcribed Image Text:

O3(g) + 3(aq) + H₂O(1) O2(g) + 13 (aq) + 2OH(aq)