To 60 g of a 3% sea salt solution was added 2 tablespoons (15 g) of dry salt. Find the mass fraction.

1. Let’s calculate the mass of salt in solution:

m1 (salt) = w1 (salt) * m1 (solution);

m1 (salt) = 0.03 * 60 = 1.8 g;

2.find the mass of salt after adding an additional portion:

m2 (salt) = m1 (salt) + mdob (salt) = 1.8 + 15 = 16.8 g;

3. calculate the mass of the resulting solution:

m2 (solution) = m1 (solution) + mdob (salt) = 60 + 15 = 75 g;

4. find the mass fraction of salt in the new solution:

w2 (salt) = m2 (salt): m2 (solution) = 16.8: 75 = 0.224 or 22.4%.

Answer: 22.4%.