Iodine VS

Iodine VS I₂ = 253.8

For a 0.5m solution Dissolve 127  g of iodine and 200  g of potassium iodide in sufficient water to produce 1000  ml.

Ascertain its exact concentration in the following manner. To 2  ml of the solution add 1  ml of 2m acetic acid and 50  ml of water. Titrate with 0.1m sodium thiosulphate VS using starch solution as indicator. Each  ml of 0.1m sodium thiosulphate VS is equivalent to 12.69  mg of I.

Store protected from light.

For a 0.05m solution Dissolve 20  g of potassium iodide in the minimum amount of water, add 12.7  g of iodine, allow to dissolve and dilute to 1000  ml with water.

Ascertain its exact concentration as described above but using 20  ml of the solution being examined and 30  ml of water.

Store protected from light.

For a 0.01m solution Add 0.3  g of potassium iodide to 20  ml of 0.05m iodine VS and add sufficient water to produce 100  ml.