What will be the mass fraction in the solution obtained by adding 50 grams of water to 150 g of a 10% solution of this salt?

Given:
m (water) = 50 g
m1 solution (salt) = 150 g
ω1 (salt) = 10%

To find:
ω2 (salt) -?

Decision:
1) Calculate the mass of salt in the solution:
m (salt) = ω1 (salt) * m1 solution (salt) / 100% = 10% * 150/100% = 15 g;
2) Calculate the mass of the resulting solution:
m2 solution (salt) = m1 solution (salt) + m (water) = 150 + 50 = 200 g;
3) Calculate the mass fraction of salt in the resulting solution:
ω2 (salt) = m (salt) * 100% / m2 solution (salt) = 15 * 100% / 200 = 7.5%.

Answer: The mass fraction of salt in the resulting solution is 7.5%.