Suppose that you are a food scientist and are studying the contribution of various sugars to obesity in the hope of identifying one that, though very sweet, has a low calorie count. What is the molality of the sugar fructose (C₆H₁₂O₆, 180.15 g · mol^–1) in a solution prepared by dissolving 90.5 g of fructose in 250. g of water?

PLAN Convert the mass of fructose into its amount of C₆H₁₂O₆ in moles, express the mass of water in kilograms, and then divide the amount of solute by the mass of solvent.