Question

When one mole of propane gas (used to cook food on an outdoor grill) undergoes complete combustion at constant pressure, is the amount of heat released the HHV or the LHV? Plz explain

Answer 1

LHV.

When propane burns it produces CO2 (gas) and H2O(liquid or gas). If H2O is in the form of gas it is LHV. If in the liquid form it is HHV. When water is vaporized from liquid to gas it requires energy to do that so you get less energy out of the propane if liquid water is vaporized.