Preparation and Standardization of 0.05 M Bromine

Bromine Solution Preparation

• Dissolve 3 g of potassium bromate and 15 g of potassium bromide in sufficient water to produce 1000 ml.
• Standardize the solution in the following manner.

Bromine Solution Standardization

• Pipette 25.0 ml of the solution into a 500 ml iodine flask and dilute with 120 ml of water.
• Add 5 ml of hydrochloric acid, insert the stopper in the flask and shake it gently.
• Add 5 ml of potassium iodide solution, again insert the stopper and allow it to stand for 5 minutes in the dark. 
• Titrate the liberated iodine with 0.1 M sodium thiosulphate using 3 ml of starch solution, added towards the end of the titration, as an indicator.
• 1 ml of 0.1 M sodium thiosulphate is equivalent to 0.01598 g of Br2.
• Store in dark amber-colored, glass-stoppered bottles.

Also see: Determination of Shelf Life of Solutions in Laboratory