Table 4. Enthalpy of solution of salts data and calculations NHẠNO3 MgSO4 2.005 1.992 [1] Mass of salt (g) [2] Volume of DI water (mL) 50.0 49.9 Mass of DI water (g) [3] Temperature of DI water (°C) 23.5 24.0 [4] Temperature of mixture after dissolution (°C) 20.5 30.6 Temperature difference (°C) [5] Total mass in reaction (g) [6] Enthalpy of solution AHsolution (cal/mol)

Table 4. Enthalpy of solution of salts data and calculations NHẠNO3 MgSO4 2.005 1.992 [1] Mass of salt (g) [2] Volume of DI water (mL) 50.0 49.9 Mass of DI water (g) [3] Temperature of DI water (°C) 23.5 24.0 [4] Temperature of mixture after dissolution (°C) 20.5 30.6 Temperature difference (°C) [5] Total mass in reaction (g) [6] Enthalpy of solution AHsolution (cal/mol)

Chemistry: Principles and Practice

3rd Edition

ISBN:9780534420123

Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Publisher:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Chapter5: Thermochemistry

Section: Chapter Questions

Problem 5.59QE

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When 50.0 g of 0.200 M NaCl(aq) at 24.1 C is added to 100.0 g of 0.100 M AgNO3(aq) at 24.1 C in a calorimeter, the temperature increases to 25.2 C as AgCl(s) forms. Assuming the specific heat of the solution and products is 4.20 J/g C, calculate the approximate amount of heat in joules produced.
When 1.000 g of ethylene glycol, C2H6O2, is burned at 25C and 1.00 atmosphere pressure, H2O(l) and CO2(g) are formed with the evolution of 19.18 kJ of heat. a Calculate the molar enthalpy of formation of ethylene glycol. (It will be necessary to use data from Appendix C.) b Gf of ethylene glycol is 322.5 kJ/mol. What is G for the combustion of 1 mol ethylene glycol? c What is S for the combustion of 1 mol ethylene glycol?
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