1. The problem statement, all variables and given/known data A 15% by mass solution has a density of 1.2 g/mL. What is the mass per liter concentration of this solution? → (a) 180 g/L (this is the answer, pretend you don't know) (b) 150 g/L (c) 125 g/L (d) cannot be determined from this information 2. Relevant equations Density Possibly percent composition 3. The attempt at a solution I don't know g/L. D=m/v I assume 15% of the solution is 15g (This is clearly not the case, or I wouldn't be here) 1.2=15/v v=12.5mL Convert mL to L 15g/0.0125mL 1200g/L <---Not even on the answer list, and sounds unreasonable anyway Without straight telling me the answer, how does one approach a question such as this?