Determine the mass of KNO3 that will be required to prepare a 15% solution weighing 510 g.

Let’s calculate the weight of the dissolved salt.

M salt = 510 x 0.15 = 76.5 grams;

Similarly, 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 (solvent) = 510 x 0.85 = 433.5 grams = 433.5 ml;

Let’s check. To do this, add the masses of the components of the solution and get the weight of the solution in question.

76.5 + 433.5 = 510;