The dissolution of calcium chloride in water CaCl2(s) → Ca²+(aq) + 2 Cl¯(aq) is used in first-aid hot packs. In these packs, an inner pouch containing the salt is broken, allowing the salt to dissolve in the surrounding water. (a) Calculate the standard enthalpy change AH° for this reaction, using data from Appendix D. (b) Suppose 20.0 g CaCl, is dissolved in 0.100L water at 20.0°C. Calculate the temperature reached by the solu- tion, assuming it to be an ideal solution with a heat capacity close to that of 100 g pure water (418 JK-!).

The dissolution of calcium chloride in water CaCl2(s) → Ca²+(aq) + 2 Cl¯(aq) is used in first-aid hot packs. In these packs, an inner pouch containing the salt is broken, allowing the salt to dissolve in the surrounding water. (a) Calculate the standard enthalpy change AH° for this reaction, using data from Appendix D. (b) Suppose 20.0 g CaCl, is dissolved in 0.100L water at 20.0°C. Calculate the temperature reached by the solu- tion, assuming it to be an ideal solution with a heat capacity close to that of 100 g pure water (418 JK-!).

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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