Calculate ΔH°f of Octane, C₈H₁₈(l), Given the Enthalpy of Combustion

question 57

Multiple Choice

Calculate ΔH°f of octane, C₈H₁₈(l) , given the enthalpy of combustion of octane to CO₂(g) and H₂O(l) , -5471 kJ/mol, and the standard enthalpies of formation of CO₂(g) and H₂O(l) , -393.5 kJ/mol and -285.8 kJ/mol, respectively.

• A) -249.2 kJ/mol
• B) +4792 kJ/mol
• C) +249.2 kJ/mol
• D) -4792 kJ/mol

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