Preparation and Analysis of Iodic Acid

Weigh out 5 g of powdered iodine into a round bottom flask provided with a reflux condenser. Add 50 cm fuming nitric acid and reflux at 90°C on a water bath in the fume cupboard for 30 minutes. Cool the flask and decant the acid solution from the yellow solid formed. Dissolve the solid in an equivolume cone, nitric acid/water to recrystallise it. Heat the ciystals gently to remove the acid. Reciystallise from hot water. Filter under suction and dry at 100°C. Store in a vacuum desiccator over cone, sulphuric acid and solid NaOH. 

Weigh out accurately 0.1 g of your preparation in 25 cm water, add 0.6 g K1 and titrate the liberated iodine as in Sec.7.3.1. Calculate from duplicate results the purity of your preparation. 

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