posted by Steve .
The thermochemical equation for the combustion of hexane is shown below. C6H14(g) + 19/2Os(g) ==> 6CO2(g) + 7H2O(g) Delta H = -4163kJ What is the enthalpy change for the combustion of 2.50g C6H14?
2.50 g/86g = .029 mol
-4163kJ/.029 = -1.43 x 10^5kJ
Wrong. You have to MULTIPLY the heat of combustion (per mole) by the number of moles. You divided, instead.