When 50cm2 of a saturated solution of sugar of molar mass 342 g at 40oC was evaporated to dryness, 34.2g of dry solid was obtained. The solubility of sugar ...

The question is asking for the solubility of sugar at 40°C given the mass of dry solid obtained after evaporating a known volume of a saturated solution of sugar. To solve this problem, we need to use the formula: Solubility = (mass of solute ÷ molar mass of solute) ÷ (volume of solvent in dm³) Using the given data, we can find the mass of sugar dissolved in 50cm³ of the saturated solution: mass of sugar = 34.2g Next, we need to calculate the number of moles of sugar dissolved: number of moles = mass of sugar ÷ molar mass of sugar = 34.2g ÷ 342g/mol = 0.1mol Finally, we can use the formula to calculate the solubility: solubility = (0.1mol ÷ 0.05dm³) = 2.0 mol dm⁻³ Therefore, the solubility of sugar at 40°C is 2.0 mol dm⁻³. The main labels for this question would be: Chemistry, Solubility, Sugar, Saturated solution, Evaporation, Molar mass, Volume, Mass.