A certain hydrocarbon of the molecular formula C,H2, has a standard enthalpy of formation AH, = -115.0 kJ/mol and a standard enthalpy of combustion AHcombust =- 4640.1 kJ/mol. What is x? Use the following data: AHF[CO2(g)] = -393.5 kJ/mol, AH [H20()] = -285.8 kJ/mol. O A. x = 6 O B. x = 5 O C. x = 8 O D. x = 7 O E. x = 4

A certain hydrocarbon of the molecular formula C,H2, has a standard enthalpy of formation AH, = -115.0 kJ/mol and a standard enthalpy of combustion AHcombust =- 4640.1 kJ/mol. What is x? Use the following data: AHF[CO2(g)] = -393.5 kJ/mol, AH [H20()] = -285.8 kJ/mol. O A. x = 6 O B. x = 5 O C. x = 8 O D. x = 7 O E. x = 4

Chemistry

9th Edition

ISBN:9781133611097

Author:Steven S. Zumdahl

Publisher:Steven S. Zumdahl

Chapter6: Thermochemistry

Section: Chapter Questions

Problem 77E: Give the definition of the standard enthalpy of formation for a substance. Write separate reactions...

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