How much dry salt is formed in the evaporation cup of 150 g of a solution with a mass fraction of this salt of 15%.

The mass of the solution is 150 grams;

To find the mass of salt, it is necessary to multiply its mass fraction by the mass of the solution.

m salt = 150 x 0.15 = 22.5 grams;

To find the mass of water, subtract the mass of salt from the mass of the solution:

m of water = 150 – 22.5 = 127.5 grams;

Check: 22.5 + 127.5 = 150;