In 500 ml of water, 25 g of salt was dissolved. The mass fraction of the substance in the resulting solution is (in%).

1. Knowing that the density of water at is 1 g / ml, we find its mass by the formula:

m (water) = p * V = 1 g / ml * 500 ml = 500 g

2. Find the mass of the resulting salt solution by the formula:

m (solution) = m (water) + m (salt) = 500 g + 25 g = 525 g

3. Let’s calculate the mass fraction of salt in the resulting solution by the formula:

w (solution) = m (salt) * 100% / m (solution) = 25 * 100/525 = 5%.