15% by mass means 15 g in 100 g solution. We can use the above and convert to 24.88 g if you wish OR
I think the easiest way to do this is to substitute into the equation for percent mass.
method 1.
15g x (24.88/100) = approx 3,7g
method 2.
(X g solute/g solution)*100 = %
(X/24.88)*100 = 15
Solve for X and I obtained approx 3.7
what mass of NaCl is contained in 24.88g of a 15% by mass solution of NaCl in water?
1 answer