How to Prepared and Standardize of 0.1 N Ceric Ammonium Sulphate Volumetric Solution.

How to Prepared and Standardize of 0.1 N Ceric Ammonium Sulphate Volumetric Solution.

                                                             

                                                                 

Preparation of 0.1 Ceric Ammonium Sulphate Volumetric solution

➤ Glass ware and instruments required.

Beaker, Glass stirrer, Graduated Pipettes, Graduated cylinder, Analytical balance, Sucker, Volumetric flask, Burette, Conical Flask, Fume hood.

➤ Reagents required.

Ceric Ammonium Sulphate Reagent Grade,

Mol. Wt. :- (2NH₄)2SO₄,Ce(SO₄)₂,2H₂O,   632.6

Sulphuric Acid AR/GR grade,

Arsenic Trioxide PS (Previously dried for 1 hr. at 105°,

Sodim Hydroxide 8% w/v,

Sulphuric Acid Dilute,

Osmic Acid Solution,

Ferroin Sulphate Solution.

➤ Preparation.

Weigh 65 g ceric ammonium sulphate reagent grade in 1000 ml volumetric flask. Dissolve in a mixture of 30ml sulphuric acid AR/GR grade  and 500ml of water  with the aid of gentle heat. Cool it to room temperature  and dilute up to the mark with water.

➤ Standardization. 

Accurately weigh about 0.2 g arsenic trioxide  PS,  previously dried for 1 hour at 105°, in  to a 500ml conical flask. Wash down the inner walls of the flask with 25 ml of 8%w/v solution of sodium hydroxide, swirl to dissolve, add 100ml of water and mix. Add 30 ml  of dilute sulphuric acid, 0.15 ml  of osmic acid  solution, 0.1 ml  of ferroin sulphate solution, and titrate with ceric ammonium sulphate solution until  the pink colour  of the solution changes sharply to pale blue colour.

➤ Calculations.

                                   g  AS₂O₃  x  0.1

N / M  = --------------------------------------------------

                          0.004946  x   Burette reading in ml