1. A student determines the molar mass of acetone, CH3COH3, by the method used in this experiment. She found that the equilibrium temperature of a mixture of ice and water was 0.5°C on her thermometer. When she added 10.5 g if her sample to the mixture, the temperature, fell to -2.6°C. She then poured off the solution through a screen into a beaker. The mass of the solution was 86.4g. a. What was the freezing point depression? °C b. What was the molality of the acetone? m c. How much acetone was in the decanted solution? d. How much water was in the decanted solution? e. How much acetone would there be in a solution containing 1 kg of water and acetone at the same concentration as she had in her experiment? g acetone f. What did she find to be the molar mass of acetone, assuming she made the calculation properly?

1. A student determines the molar mass of acetone, CH3COH3, by the method used in this experiment. She found that the equilibrium temperature of a mixture of ice and water was 0.5°C on her thermometer. When she added 10.5 g if her sample to the mixture, the temperature, fell to -2.6°C. She then poured off the solution through a screen into a beaker. The mass of the solution was 86.4g. a. What was the freezing point depression? °C b. What was the molality of the acetone? m c. How much acetone was in the decanted solution? d. How much water was in the decanted solution? e. How much acetone would there be in a solution containing 1 kg of water and acetone at the same concentration as she had in her experiment? g acetone f. What did she find to be the molar mass of acetone, assuming she made the calculation properly?

Chemistry: Principles and Practice

3rd Edition

ISBN:9780534420123

Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Publisher:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Chapter5: Thermochemistry

Section: Chapter Questions

Problem 5.61QE: When 7.11 g NH4NO3 is added to 100 mL water, the temperature of the calorimeter contents decreases...

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