Calculate the mass of water and sodium chloride required to prepare 150 g of sodium chloride solution with

Calculate the mass of water and sodium chloride required to prepare 150 g of sodium chloride solution with a mass fraction of 20%. What will the mass fraction of sodium chloride be if you add 50 g of water to the resulting solution?

M solution = M water + M salt = 150 grams;

The mass fraction of the component of the solution will be equal to the ratio of its weight to the weight of the solution.

Find the mass of salt in the solution.

M salt = 150 x 0.2 = 30 grams;

Find the mass of water in the solution.

M water = 150 x 0.8 = 120 grams;

Let’s check:

To do this, add the concentrations of the constituents of the solution.

30 + 120 = 150;

If you add 50 grams of water to the solution, then the salt concentration will be:

With salt 2 = 30 / (150 + 50) = 0.15 = 15%;