I was thinking of methane as input. But what about it as output? How much does leave the system? And should this not be in calories "out" column, but I don't think that is usually counted there...
Could you elaborate on what you mean? What does methane have to do with this and what is the "out" column?
Calorimetry is just measuring the heat transfer from combustion, usually by measuring the temperature change of a known quantity of water in the classical experiment. You perform versions of it in high school and undergrad
Calories are just a unit of energy, and heat can be related back to energy (joules for people using SI)
Well some of the food we eat generates flatulence of which 7% can be methane. Meaning this leaves our system without burning. As such in calorimeter it would be unburned fuel. Meaning that some calories are not absorbed failing the calories in and out equation.
Yes absolutely. Not only that but plenty of our food passes through undigested whatsoever. In theory we can't control that so we can only measure calories ingested, not calories absorbed but it hopefully sheds light on the fact that this is more complicated than just a number
