25 g of the substance was dissolved in 75 g of water. The mass fraction of the substance (%)

25 g of the substance was dissolved in 75 g of water. The mass fraction of the substance (%) in the resulting solution is equal to.

The solution consists of two components: water weighing 75 grams and a substance weighing 25 grams.

The mass of the solution is equal to the sum of their masses:

m solution = 75 + 25 = 100 grams.

To find the mass fraction of salt, we divide the mass of the substance by the mass of the solution:

C = m substance / m solution = 25/100 = 0.25 = 25%;