At this temperature, the solution can hold a maximum of approximately 190 g of potassium iodide per 100 mL of water. At 40^@"C", 180 g of potassium iodide will actually make for an unsaturated solution, since the maximum solubility at this temperature is 190 g per 100 mL.
Approx. 190g... By definition, rho, is given by the quotient.... rho_"density"="mass"/"volume", and thus has units of gmL^-1-=g*cm^-3... And so we simply rearrange ...