A student was instructed to determine the molecular weight of an unknown white powder. He remembered that one way to do this is by exploiting the colligative properties of solution. After a simple conductivity test, he found that an aqueous solution of the sample is not conductive. He dissolved 24.53 grams of the unknown sample in 0.750 kg of water. He found that the boiling point of the resulting solution was 100.78 °C under normal atmospheric conditions. Given: K, of water is 0.512 °C/m a. Calculate the molality of the resulting solution. b. How many moles of the sample did he dissolve to perform the experiment? c. What is the molecular weight of the unknown sample?

A student was instructed to determine the molecular weight of an unknown white powder. He remembered that one way to do this is by exploiting the colligative properties of solution. After a simple conductivity test, he found that an aqueous solution of the sample is not conductive. He dissolved 24.53 grams of the unknown sample in 0.750 kg of water. He found that the boiling point of the resulting solution was 100.78 °C under normal atmospheric conditions. Given: K, of water is 0.512 °C/m a. Calculate the molality of the resulting solution. b. How many moles of the sample did he dissolve to perform the experiment? c. What is the molecular weight of the unknown sample?

Chemistry: An Atoms First Approach

2nd Edition

ISBN:9781305079243

Author:Steven S. Zumdahl, Susan A. Zumdahl

Publisher:Steven S. Zumdahl, Susan A. Zumdahl

Chapter10: Properties Of Solutions

Section: Chapter Questions

Problem 7RQ

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