Calorific value of parformaldehyde or formaldehyde

Calorific value is also called calorific value or calorific value. 　　In fuel chemistry, an important indicator of fuel quality. The amount of heat released when a unit weight (or volume) of fuel is completely burned. 　　Usually measured with a calorimeter (calorie meter) or calculated from fuel analysis results. There are two types: higher calorific value (higher calorific value) and lower calorific value (lower calorific value). The former is the total heat of combustion of the fuel and the heat of condensation of water vapor, that is, the total heat released when the fuel is completely fueled. The latter is simply the heat of combustion of the fuel, which is the difference from the total heat minus the heat of condensation. Commonly used units of calorific value are kJ/kg (solid fuel and liquid fuel), or kJ/m^3 (gaseous fuel). 　　The heat released by the complete combustion of 1 kilogram (cubic meter) of a certain solid (gas) fuel is called the calorific value of the fuel. It is a property of matter. The symbol is q. The unit is Joules per kilogram. The symbol is J/kg (J/m^3). 　　Calculation formula Calculation formula for heat released by complete combustion of solid fuel: Q=mq Calculation formula for heat released by complete combustion of gaseous fuel: Q=Vq Q represents heat (J), q represents calorific value (J/(kg * ℃) ), m represents the mass of solid fuel (kg), and V represents the volume of gaseous fuel (m^3. 　　q=Q/m(solid) ； q=Q/v (gas) W=Q=mq=Q/m W=Q=Vq=Q/v (W: Total work) Personal understanding is that calorific value and combustion enthalpy are the same thing, they are just called different things. To test my point, calculations were performed for methane to prove my understanding. It can be found in physical chemistry books that the combustion enthalpy of formaldehyde is 570.78KJ/mol, so the calorific value of formaldehyde is 570.78 * 1000/30=19026KJ/Kg If you want to convert to KJ/M3, just multiply it by the density of formaldehyde. There may be ready-made manuals for reference. I hope that those who know can share them and verify my calculation results. One family’s opinion, for reference only. Corrections welcome!

Thank you, man! After checking the information, it seems that the heat enthalpy also includes phase change and so on. The calorific value and combustion enthalpy are almost the same. You can convert them according to your method.