|MadSci Network: Earth Sciences|
"Burning" typically describes a chemical reaction called oxidation. When burning something like wood, a simple model of the chemical reaction is : C12H22O11 + 12O2 --> 12CO2 + 11H20 Complete conversion to carbon dioxide and water represents a total burn in this example. More oxygen makes the reaction proceed at a faster rate and more completely. However, there are competing reactions. For example, carbon monoxide (CO) or formaldehyde might form instead of carbon dioxide (CO2), or the wood might react with nitrogen oxides and produce urban smog. Increasing oxygen will help prevent this. So, if the air was pure oxygen, there would be less smog, carbon monoxide, and other by-products formed directly from the burn. However, in a pure oxygen atmosphere, it would be near impossible to actually put out a forest fire, or any ordinary fire for that matter, because the reaction would proceed too readily. It would be a give and take. "Burning" is actually a really complicated reaction involving radicals and reverse reactions, and I've simplified a lot here, but I hope this clears things up anyway.
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