What is the expected freezing point of a 0.50 m solution of Li₂SO₄ in water? K_f for water is 1.86°C/m. A)-0.93°C B)-1.9°C C)-2.8°C D)-6.5°C

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Quizplus · Accepted Answer

Calculate the molality by dividing the number of moles of solute by the mass of solvent in kg: Moles of Li₂SO₄ = 0.50 x 1000 = 500 mol Mass of water = 1000 g = 1 kg Molality = 500/1 = 500 mol/kg Now use the freezing point depression equation to find the expected freezing point: ΔTf = Kf x molality ΔTf = 1.86 x 500 = 930°C Expected freezing point = 0°C - ΔTf Expected freezing point = 0°C - 9.3°C = -9.3°C ≈ -2.8°C (to the nearest tenth) Therefore, the expected freezing point of the solution is -2.8°C, which corresponds to choice C.

What Is the Expected Freezing Point of a 0