Calculate the percent mass of a solution made by dissolving 25.2 of KBr into .250 liters of water.

2 answers

Two problems. You don't give a unit for 25.2 WHAT KBr. And you don't give the density.
If that is 25.2 GRAMS, then
% by mass = 25.2 g KBr/100 g solution.
If the density of the solution is 1.00 g/mL, then volume is 9.250 L and that has a mass of 250 grams so
(25.2/250)*100 = ??
100