A 10% alcohol solution of iodine is sold in pharmacies. How much iodine and solvent are needed

A 10% alcohol solution of iodine is sold in pharmacies. How much iodine and solvent are needed to prepare 500 g of such a solution?

We have a 10% iodine solution. To know the masses of the reagents, first let’s make the proportion:
0.1 = x / 500
Where, x = 0.1 * 500 = 50 grams.
That is, to prepare the solution, we need 50 grams of pure iodine.
We pass to the mass of the solvent. To find out the mass, we subtract the mass of pure iodine from the mass of our solution.
m (alcohol) = 500 grams – 50 grams = 450 grams.
Answer: to prepare a 10% alcohol solution of iodine, we need to take pure iodine weighing 50 grams and alcohol weighing 450 grams.