Calculate the freezing point of a solution of 20.0 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)-1.05°C B)1)05°C C)4)45°C D)6)54°C

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Quizplus · Accepted Answer

The freezing point depression can be calculated using the formula ΔTf = i * Kf * m, where i is the van't Hoff factor (1 for non-electrolytes like methyl salicylate), Kf is the freezing point depression constant, and m is the molality of the solution. First, calculate the molality: moles of solute = 20.0 g / 152.15 g/mol = 0.1314 mol; molality = 0.1314 mol / 0.800 kg = 0.1643 m. Then, ΔTf = 1 * 5.10°C/m * 0.1643 m = 0.838°C. The new freezing point = 5.50°C - 0.838°C = 4.662°C, approximately 4.45°C.

Calculate the Freezing Point of a Solution of 20