Question

"We need to prepare 150 ml of a 20 g/L solution of iodine. How much iodine and water do we need?"

The exercise answer is: 3 g of I2 and 150 ml of water

Why 150 mL of water? It shouldn't be water till 150mL to achieve the final solution correctly?

Thanks! :)

Answer 1

Answer is given below -

While practically performing the experiment, solid is put in the conical flask first. After that total amount of water to be poured is measured in measuring cylinder.

Little amount of water from measuring cylinder is poured in flask, to mix the solution completely.

After that remaining amount of water is poured and mixed well.

This is practical way of preparing the solution, but while mentioning in the book or copy, it is always written as - to take 150 ml of water