|MadSci Network: Physics|
In order to burn something you need three things. Oxygen, Heat, and Fuel. Take away any one, no fire. You might be interested in the fuel portion. When you burn something, it is called combustion in chemistry. Fuel + Oxygen ----heat---> products + energy The combustion breaks chemical bonds, which store energy. So it depends on what you burn, how much energy you get out. My only guess with your question is that paper (i.e. wood pulp) is made of atoms and molecules which release more energy under combustion than say methane gas.
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