Question

what is the enthalpy of combustion of a compound if it's enthalpy of formation is -520 KJ/mol and if the total enthaply of formation of its products is -670 KJ/mol

Answer 1

Thus, to yield the enthalpy of the combustion reaction, we then sum the enthalpies of formation of the products, weighted by their stoichiometric coefficients, and subtract the enthalpy of formation of ethanol (-277.69kJ/mol). The result is ethanol's standard enthalpy of combustion of -1234.79kJ/mol.