Water and acetonitrile, CH3CN, are miscible (can be mixed in any proportions). However, when water and acetonitrile are mixed, the volumes are not additive (the total volume of the resulting solution is not equal to the sum of the pure liquid volumes). For example, when 100.0 mL of water and 100.0 mL of CH3CN(1), are mixed at 20 °C, the total volume of the solution is 192.0mL, not 200.0 mL. a. Provide an explanation for this phenomenon. b. Calculate the molarity, molality and mol fraction of CH3CN in a solution prepared by mixing 100.0 mL of water and 100.0 mL of CH3CN(1) at 20 °C. The total volume of the mixture is 192.0 mL and the densities of water and acetonitrile are 0.998 g/mL and 0.782 g/mL, respectively, at this temperature. c. [When 70.0 g H2O and 190.0 g CH3CN(1) are mixed, to resulting solution has a density of 0.860 g/mL at 20 °C. Calculate the volumes of the pure liquid samples and the solution, and show that the pure liquid volumes are not additive.

Water and acetonitrile, CH3CN, are miscible (can be mixed in any proportions). However, when water and acetonitrile are mixed, the volumes are not additive (the total volume of the resulting solution is not equal to the sum of the pure liquid volumes). For example, when 100.0 mL of water and 100.0 mL of CH3CN(1), are mixed at 20 °C, the total volume of the solution is 192.0mL, not 200.0 mL. a. Provide an explanation for this phenomenon. b. Calculate the molarity, molality and mol fraction of CH3CN in a solution prepared by mixing 100.0 mL of water and 100.0 mL of CH3CN(1) at 20 °C. The total volume of the mixture is 192.0 mL and the densities of water and acetonitrile are 0.998 g/mL and 0.782 g/mL, respectively, at this temperature. c. [When 70.0 g H2O and 190.0 g CH3CN(1) are mixed, to resulting solution has a density of 0.860 g/mL at 20 °C. Calculate the volumes of the pure liquid samples and the solution, and show that the pure liquid volumes are not additive.

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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