The oxidation of the thiosulphate ion to tetrathionate ion, is used to estimate iodine: The disappearance of iodine at the end point is detected by the addition of fresh starch solution which gives a blue complex as long as iodine is present.
The oxidation of the thiosulphate ion to tetrathionate ion, is used to estimate iodine: The disappearance of iodine at the end point is detected by the addition of fresh starch solution which gives a blue complex as long as iodine is present.