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Ch.13 - Solutions
All textbooksTro 4th EditionCh.13 - SolutionsProblem 109
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Chapter 13, Problem 109

What is the freezing point of an aqueous solution that boils at 106.5 °C?

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Identify the boiling point elevation formula: \( \Delta T_b = i \cdot K_b \cdot m \), where \( \Delta T_b \) is the boiling point elevation, \( i \) is the van't Hoff factor, \( K_b \) is the ebullioscopic constant, and \( m \) is the molality.
Calculate the boiling point elevation: \( \Delta T_b = 106.5 \, ^\circ\text{C} - 100 \, ^\circ\text{C} \).
Use the boiling point elevation to find the molality \( m \) of the solution: \( m = \frac{\Delta T_b}{i \cdot K_b} \). Assume \( i = 1 \) for a non-electrolyte unless specified otherwise.
Identify the freezing point depression formula: \( \Delta T_f = i \cdot K_f \cdot m \), where \( \Delta T_f \) is the freezing point depression and \( K_f \) is the cryoscopic constant.
Calculate the freezing point of the solution: \( T_f = 0 \, ^\circ\text{C} - \Delta T_f \).
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