• OpenStars@piefed.social
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    5 天前

    Air is on fire.

    Unless the fire was in space I suppose - which can’t happen, so yeah, air is always on top of fire.

    Edit: nope, I was wrong. Air is not always on top of fire :-P.

      • Skyrmir@lemmy.world
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        5 天前

        The reaction propagation is always from the ignition source to the media, so the ‘fire’ is always on the outside. Even if the inside is in the process of quickly becoming the outside.

        • HikingVet@lemmy.ca
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          5 天前

          No, I get that. Not why I asked the question.

          If you have a compound like potassium super oxide chatch light in a vacuum, does it still burn because it has it’s own oxidizer?

          • Skyrmir@lemmy.world
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            5 天前

            By itself in a vacuum, no. Under gas pressure, when contacted by water it will react from the point of contact until all reactants are complete. I wouldn’t consider the reaction to be ‘fire’ though. At least not personally. Drop some hydrocarbons in the mix and you’ll get a fire as the oxygen produced gets something to react with.

          • higgsboson@piefed.social
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            5 天前

            Yes, that is how rockets get to space, for example. Earth’s atmo is ~21% Oxygen. So that is giving flames a boost. Careful not conflate “burn” with the presence of flames. In a vacuum, the flame could only exist briefly because there isnt the available Oxygen from the air. The reaction will (or might?) still happen, but without the oxygen to produce a flame.

            BTW, this has been studied in microgravity aboard the ISS.

    • huppakee@piefed.social
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      5 天前

      Maybe the dutch partly learned from the vikings because we do it the other way around: “The thing is in fire!”

    • chuckleslord@lemmy.world
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      5 天前

      Converting the hydrocarbons to CO2 and H2O, yes.

      Also, just found out that the red and yellow “flames” are actually heated soot that’s glowing, like metal glows when heated. That’s why “hotter” fires glow blue, that’s actually the chemical of the gasses burning and less soot is being produced. That’s why it’s counter intuitive why colder flames glow brighter than hotter ones.

  • BowtiesAreCool@lemmy.world
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    5 天前

    Fire blanket, it’s briefly “on” fire, until it isn’t anymore. Or until fire is on it too. Fire blankets are the liminal spaces of fire.