The freezing point of a substance is the temperature at which the solid and liquid forms can coexist indefinitely, at equilibrium. Under these conditions molecules pass between the 2 phases at equal rates because their escaping tendencies from the two phases are identical. Like the boiling point elevation, the freezing point of a solution is directly proportional to the molal concentration of the solution, that is, AT=Krm Where, ATr refers to the freezing point lowering, Kf, the freezing point depression constant, and m, the molality of the solution. Some of the Kf values are shown in Table 1. For water, Kf is 1.86 °C/m, therefore, any 1 m aqueous solution of nonvolatile solute or a 0.5 m aqueous solution of NaCI will freeze at 1.86 °C lower than pure water. EXERCISE: Problem Solving: Show your solution! 1. A solution containing a nonelectrolyte dissolved in water has a boiling point of 0.305 °C. Calculate the freezing point of the same solution.

The freezing point of a substance is the temperature at which the solid and liquid forms can coexist indefinitely, at equilibrium. Under these conditions molecules pass between the 2 phases at equal rates because their escaping tendencies from the two phases are identical. Like the boiling point elevation, the freezing point of a solution is directly proportional to the molal concentration of the solution, that is, AT=Krm Where, ATr refers to the freezing point lowering, Kf, the freezing point depression constant, and m, the molality of the solution. Some of the Kf values are shown in Table 1. For water, Kf is 1.86 °C/m, therefore, any 1 m aqueous solution of nonvolatile solute or a 0.5 m aqueous solution of NaCI will freeze at 1.86 °C lower than pure water. EXERCISE: Problem Solving: Show your solution! 1. A solution containing a nonelectrolyte dissolved in water has a boiling point of 0.305 °C. Calculate the freezing point of the same solution.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter11: Properties Of Solutions

Section: Chapter Questions

Problem 70E: The vapor pressures of several solutions of water-propanol (CH3CH2CH2OH) were determined at various...

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