A-LevelChemistryAnalytical techniquesOct/Nov 2017Paper 3 Q114 Marks
In this experiment you will determine the oxidation number of iodine in one of its compounds by titration. FA 1 is a 0.0197 mol dm-³ solution of the iodine-containing compound. FA 2 is dilute sulfuric acid, H₂SO₄. FA 3 is aqueous potassium iodide, KI. FA 4 is 0.105 mol dm-³ sodium thiosulfate, Na₂S₂O₃. starch indicator FA 1 reacts with excess acidified potassium iodide to produce iodine, I₂. This iodine is then titrated with aqueous sodium thiosulfate using starch indicator.
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