Chemistry
10th Edition
ISBN: 9781305957404
Author: Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher: Cengage Learning
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KBr dissociates in water according to the following equations:
KBr(s) --> K+(aq) +Br-(aq)
a) 10.5g of KBr are dissolved in 125g of water in a calorimeter and you observe the temperature of the water decrease from 24.2 to 21.10 Celsius. What is the enthalpy of the solution of KBr in kj/mol? Heat capacity of solution is 4.184 J/gC. Molar mass of KBr is 119.0g/mol.
b) Explain why the dissolving of KBr in the water is endothermic OR exothermic reaction? Explain.
c) If you dissolved 24.0g of KBr in water, would you expect the temperature of the water to increase or decrease? Explain.
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