Determine the vapour pressure of a solution at 28 °C that contains 62.5 g of fructose (C₆H₁₂O₆) in 325.0 mL of water. The vapour pressure of pure water at 28 °C is 28.3 Torr. A) 27.8 Torr B) 16.9 Torr C) 28.8 Torr D) 36.9 Torr E) 24.9 Torr

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Quizplus · Accepted Answer

The vapour pressure of the solution can be calculated using Raoult's Law: P_solution = X_solvent * P_pure solvent. First, calculate the mole fraction of water (solvent). Moles of fructose = 62.5 g / 180.18 g/mol = 0.347 moles. Moles of water = 325 g / 18.015 g/mol = 18.04 moles. Mole fraction of water = 18.04 / (18.04 + 0.347) = 0.981. P_solution = 0.981 * 28.3 Torr = 27.8 Torr.

Determine the Vapour Pressure of a Solution at 28 °C