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 22.87 grams of the unknown sample in 0.500 kg of water. He found that the boiling point of the resulting solution was 100.13 °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?

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 22.87 grams of the unknown sample in 0.500 kg of water. He found that the boiling point of the resulting solution was 100.13 °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?

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

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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Concept explainers

Solutions

Solutions can be considered as homogeneous mixtures which contain two or more than two chemical substances. The chemical substance which is the greater part is defined as solvent. And the chemical substance that is dissolved in a solvent is referred to as solute. Solution chemistry plays an important role in chemistry since it supports many commercial applications of solutions.

Question

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 22.87 grams of the unknown
sample in 0.500 kg of water. He found that the boiling point of the resulting solution
was 100.13 °C under normal atmospheric conditions.
Given: Kp 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?

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