In 350 water added 20 g of salt, calculate the mass fraction of salt in the solution.

Given:
m (water) = 350 g
m (salt) = 20 g

Find:
ω (salt) -?

Solution:
1) First, you need to calculate the mass of the salt solution:
m solution (salt) = m (salt) + m (water) = 20 + 350 = 370 g;
2) Having all the necessary data, you can calculate the mass fraction of salt in the solution:
ω (salt) = m (salt) * 100% / m solution (salt) = 20 * 100% / 370 = 5.4%.

Answer: The mass fraction of salt is 5.4%.