• Donjuanme@lemmy.world
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    1 year ago

    Some metals (the ones that require super special fire extinguishers) can keep an exothermic reaction going (magnesium I believe, and sodium I’m pretty sure) but rapid oxidation (rusting) is the most common method of combustion.

    Oxygen is so combustible that it’s toxic to life, and would have killed life as it was a billion years ago (number from my ass) which produced oxygen as a byproduct of photosynthesis if it weren’t for the development of mitochondria.

    A few other things (elements) can burn without oxygen, but not many, and they normally need a pretty large activation temperature.

    • ThatWeirdGuy1001@lemmy.world
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      1 year ago

      So is it just the definition of “fire” itself? Like only something burning with oxygen is “fire” but if it’s another fuel source it’s not technically “fire” but we call it fire anyway?

      • Donjuanme@lemmy.world
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        1 year ago

        Burning with oxygen is oxidation, things oxidize when the element oxygen binds with another element, which it’s very prone to doing. Oxidation with iron is rust, it just happens much more slowly (but still exothermically) than when biological compound oxidize they release energy more rapidly, rapidly enough to cause other nearby organic bonds to break and expose themselves to sites for more oxidation to take place.

        There can be electrical fires, chemical fires, classic fires, and self fueling fires (the kind you were originally asking about). There are probably more categories now. Always be sure to use the proper fire extinguisher for the fire at hand.