Why doesn't coal have a flame?

  1. Wood burns with flame but coal does not. Why?
  2. jcsd
  3. SteamKing

    SteamKing 10,954
    Staff Emeritus
    Science Advisor
    Homework Helper

    You sure about that?
  4. tiny-tim

    tiny-tim 26,016
    Science Advisor
    Homework Helper

    imitation coal fires have imitation flames :wink:

    (i can see one from my little bowl! o:))
  5. A flame is the result of flammable gases being heated, flowing up, and reacting with oxygen where the gases encounter the atmosphere. In a candle flame, the reaction generates enough heat to drive further gas generation and convection; with a gas stove, the burner keeps providing more fuel; either way you get a steady state, which is the flame.
    Coal does have a small flame, as anyone old enough to have stoked a coal furnace (in their pajamas on a January morning) can testify.
    Coke, or charcoal, generally has no visible flame, because there are no flammable gases generated from pure carbon. (Under condidtions of poor ventilation, there will be carbon monoxide generated, but CO doesn't combust readily enough to support a flame ... that's why burning charcoal indoors is a recipe for disaster.)
  6. DrClaude

    Staff: Mentor

    This thread is 2 years old and the OP hasn't been on PF for almost a year. There is not point in responding anymore.

    Thread locked.
    berkeman likes this.
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