Calculate the freezing point of a solution of 30.0 g methyl salicylate,C₇H₆O₂,dissolved in 800.g of benzene,C₆H₆.K_f for benzene is 5.10°C/m and the freezing point is 5.50°C for benzene. A)-1.56°C B)1.56°C C)3.93°C D)7.06°C

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Quizplus · Accepted Answer

First, calculate the molality of the solution: Molar mass of C7H6O2 = 138.12 g/mol. Moles of solute = 30.0 g / 138.12 g/mol = 0.217 mol. Molality (m) = 0.217 mol / 0.800 kg = 0.27125 m. Freezing point depression (ΔTf) = Kf * m = 5.10°C/m * 0.27125 m = 1.38°C. New freezing point = 5.50°C - 1.38°C = 4.12°C. The closest option is 3.93°C.

Calculate the Freezing Point of a Solution of 30