To 300 g of acid solution, in which the mass fraction of acid is 10%, 50 g of acid

To 300 g of acid solution, in which the mass fraction of acid is 10%, 50 g of acid was added. Calculate the mass fraction of acid in the resulting solution.

Progress:
1) Calculation of the mass of the solute of the acid in its solution.
2) Calculation of the mass of the solute after adding acid.
3) Calculation of the mass of the solution after adding acid.
4) Calculation of the mass fraction of the substance in the resulting solution.
Solution:
1. The mass of the solute is expressed from the formula for finding the mass fraction:
W = (mr.v – wa / mr – pa) * 100%.
10 = x / 300 * 100.
x = 30g.
2. Once acid is added to the solution, the mass of the solute and the mass of the solution will change.
30 + 50 = 80g.
3.300 + 50 = 350g.
4.W = (80/350) * 100 = 22.9% – the answer.