You have 4.0 g of solid A, 100.00 mL of water (100.0 g of water), and the total mass of solid A combined with 100.00 mL of water is found to be 104.0 g. The mass percent of A in this solution is ...

Answer 1

Mass percent (w/w) is defined as the mass of the solute/mass of solution and all of that times 100.
(4.0/104)*100 = ??
Watch the number of significant figures.

Answer 2

thanks!