Question

The solute potassium chloride (KCl) is dissolved in the solvent water (H2O) to produce a homogeneous solution. The solution contains 15.0% of KCl by mass. What mass of water is
contained in 200. grams of this solution?

Answer 1

if you have a 15% by mass solution of KCl, it means you have 15 g of KCl in 100 g of solution (meaning you have 85 grams of water in 100 grams of solution)

100g-15g=85 g

so in 200 g of solution you have 30 grams of KCl, right?

Answer 2

Find out 15% of 200g
200/100x15 = 30g of KCl

200g-30g = 170g of H2O

So surely it would be 170g of water by mass and 30g of KCl

Answer 3

Oh. That was a dumb question. Thanks, guys.