To 70 g of a 20% solution of iron sulfate 3 added 30 g of water and 20 g of salt, calculate the mass

To 70 g of a 20% solution of iron sulfate 3 added 30 g of water and 20 g of salt, calculate the mass fraction of salt in the solution?

1 Calculate the mass of the solute of ferrous sulfate. To do this, we multiply the mass fraction of the substance by the mass of the solution and divide by one hundred percent: 20 * 70/100 = 14g.
2 Calculate the mass of the solute of ferrous sulfate after adding salt: 14 + 20 = 34g.
3 Calculate the mass of the solution after adding salt and water: 70 + 20 + 30 = 120g.
4 Find the mass fraction of ferrous sulfate in the solution after adding salt and water:
W = 34/120 * 100 = 40.8% – the answer.