What mass of salt and water should be taken to prepare a 150 g solution with a mass fraction of 30%?

Let’s calculate the weight of the dissolved salt.

M salt = 150 x 0.3 = 45 grams;

In the same way, we find the weight of the solvent (water).

(In the calculations, we will make the assumption that the density of water is 1 gram / ml).

M water = 150 x 0.7 = 105 grams = 105 ml;

Let’s check. To do this, we sum up the masses of the components of the solution and obtain the mass of the required solution.

45 + 105 = 150;