Nitroglycerin (C3H5N3O9), a liquid at room temperature (25 °C) and atmospheric pressure (1.01325 x 105 Pa), is used to relieve angina. It may undergo decomposition under these same conditions to form nitrogen, carbon dioxide, oxygen and water, with an enthalpy of decomposition of -1541 kJ mol-¹. The standard enthalpies of formation of water and carbon dioxide are -285.9 and -393.5 kJ mol-¹ respectively. (a) Calculate the work done when 1.0 moles of nitroglycerin decomposes and additionally explain the significance of the sign.

Nitroglycerin (C3H5N3O9), a liquid at room temperature (25 °C) and atmospheric pressure (1.01325 x 105 Pa), is used to relieve angina. It may undergo decomposition under these same conditions to form nitrogen, carbon dioxide, oxygen and water, with an enthalpy of decomposition of -1541 kJ mol-¹. The standard enthalpies of formation of water and carbon dioxide are -285.9 and -393.5 kJ mol-¹ respectively. (a) Calculate the work done when 1.0 moles of nitroglycerin decomposes and additionally explain the significance of the sign.

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter12: Thermodynamic Processes And Thermochemistry

Section: Chapter Questions

Problem 41P

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