Starts from a solution of hydrogen peroxide with sulfuric acid. To this is added solution containing potassium iodide, sodium thiosulfate, and starch. There are two reactions occurring in the solution.
In the first, slow reaction, triiodide is produced:
H2O2 + 3I− + 2H+ → I3− + 2H2O
In the second, fast reaction, triiodide is reconverted to 3 iodide ions by the thiosulfate:
2S2O32− + I3− → S4O62− + 3I−
In the first, slow reaction, triiodide is produced:
H2O2 + 3I− + 2H+ → I3− + 2H2O
In the second, fast reaction, triiodide is reconverted to 3 iodide ions by the thiosulfate:
2S2O32− + I3− → S4O62− + 3I−
