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5. ESTIMATION OF IRON, , Ex. No.: Date:, Aim, , To estimate the amount of iron present in ............ mL of the given ferrous sulphate solution, supplied in bottle (A) using a standard solution of ferrous ammonium sulphate provided in bottle, (©) of normality ............ N and an approximately decinormal solution of potassium permanganate, in bottle (B), Principle, , The titration is based on the oxidation and reduction reaction. The oxidising agent, Potassium, permanganate oxidises the reducing agent, ferrous sulphate and ferrous ammonium sulphate in, acidic medium to ferric sulphate., , , , , , , , , , , , , , , , , , , , Procedure, Short Procedure, DESCRIPTION TITRATION -I TITRATION - II, Burette solution _| Potassium permanganate (B) Potassium permanganate(B, Pipette solution Ferrous ammonium sulphate Ferrous sulphate solution(A), solution(C), Reagents added 20 mL of dilute sulphuric acid 20 mL of dilute sulphuric acid, Indicator Self (KMnO4) Self (KMn0O4), End point Appearance of permanent pale Appearance of permanent, pink colour pale pink colour, Equivalent mass of iron = 55.85, , , , , , , , Titration —I, Standardisation of Potassium permanganate solution, , The burette is washed with water, rinsed with distilled water and then with the given, potassium permanganate solution. It is filled with same solution up to zero mark. The initial reading, of the burette is noted. A 20 mL pipette is washed with water, rinsed with distilled water and then, with the given ferrous ammonium sulphate solution. 20 mL of ferrous ammonium sulphate solution, is pipetted out into a clean conical flask. One test tube full of sulphuric acid (20 mL) is added into, the flask. The solution is titrated against potassium permanganate solution taken in the burette., Potassium permanganate acts as the self-indicator. The end point of the titration is the appearance of, pale permanent pink colour. The titration is repeated to get concordant titre value. From the titre, value, the normality of potassium permanganate solution is calculated., , 138