400 ml of solution (density 1.5 g / ml) contains 300 g of solute. Calculate the mass fraction of the solute.

Given:
V solution = 400 ml
ρ solution = 1.5 g / ml
m in-va = 300 g
To find:
ω in-va -?

Decision:
1) find the mass of the solution:
m solution = V solution * ρ solution = 400 * 1.5 = 600 g
2) find the mass fraction of the solute:
ω in-va = m in-va * 100% / m solution = 300 * 100/600 = 50%
Answer: the mass fraction of the solute is 50%.