| 0.1M Ceric Ammonium Sulphate |
| 1.0 Scope: This GTP is apply for preparation and standardization of 0.1M ceric ammonium sulphate. 2.0 Apparatus: 1000ml, 250ml and 100ml volumetric flask 500 glass-stoppered, conical flask 100ml graduated burette 25ml and 1ml volumetric pipette 3.0 Reagents: Ceric ammonium sulphate AR grade Arsenic trioxide AR grade Sodium hydroxide solution (8 % w/v) Sulphuric Acid AR grade Dilute sulphuric acid solution Osmic acid solution Ferroin sulphate solution To Read this GTP click here Preparation of Standardization 0.1M Ceric Ammonium Sulphate. 4.0 Preparation: Dissolve 65 g of ceric ammonium sulphate, with the aid of gentle heat, in a mixture of 30.0 ml of sulphuric acid and 500 ml of purified water. Cool, filter the solution, if turbid, and dilute to 1000 ml with water. 5.0 Standardization: Take 0.20 gm or of arsenic trioxide(As₂O₃), previously dried at 105 degree Celsius for 1 hour, and transfer to a 500 ml conical flask. Take 25.0 ml of an 8.0% w/v soln. of sodium hydroxide(NaOH), swirl to dissolve in a flask, add 100 ml of purified water/water for injection and mix. Add 30.0 ml of dilute sulphuric acid, 0.15 millilitre of osmic acid soln, 0.1 ml of ferroin sulphate solution and slowly titrate with the ceric ammonium sulphate soln. until the pink colour is changed to a very pale blue, adding the titrant slowly towards the end-point. Each ml of 0.1M ceric ammonium sulphate is equivalent to 0.004946 gm of As2O3. 6.0 Calculation: N = W X 0.1 / Volume consume X 0.004946Where: N = molarity of ceric ammonium sulphate solution W = weight of arsenic trioxide in g Volume consume = Consumed volume of 0.1M ceric ammonium sulphate solution in ml. 7.0 Storage: Stored in a transparent glass stoppered bottle. |
