# Heat given by a flame

by LorDjidane
Tags: flame, heat
 P: 6 Hello First of all, I'm french, as a consequence my scientific language might be difficult to understand. I'm sorry for this. So, I'm studying a little Stirling motor. I evaluated the Work given by its cycle. It functions with an external combustion, produced by the burning of Ethanol (C2H5O). I want to calculate the Heat given by the flame provided by this combustion in order to calculate the output of my motor. Does anyone have an idea ? I thought about the use of the Free Enthalpy of Combustion, but I don't understand how to use it. Maybe I could use the expression : Variation of enthalpy = C*variation of temperature ? Thanks for your help =)
 Sci Advisor HW Helper P: 1,769 Are you referring to free energy? You might want to find the standard enthalpy of reaction instead. The data is quite easy to find.
 P: 6 That must be that (attached with the post). But with that, how could I calculate the heat given by my flame ? Attached Images
I think that enthalpy is a good approximation of the heat $q$ in most cases,