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Latent heat of ashes

  1. Feb 25, 2010 #1
    I asked my teacher this but he did not know so he asked me to find out. When you set fire to something (for example paper) then when it burns all of the heat is released, is this the reason why ashes become cold so quickly?
  2. jcsd
  3. Feb 25, 2010 #2
    Ashes are primarily composed of carbon(the result of the chemical reaction that fueled the burning). Carbon, as listed on a periodic table is a nonmetal. A common trend among non-metallic elements is their low capacity to conduct heat. This might explain why the ashes of the spent fuel that was your paper may seem so cool.
  4. Feb 25, 2010 #3
    What are you talking about?
    Latent heat is the heat absorbed or released during a phase transition.But here I see no phase transition,only combustion.
  5. Feb 25, 2010 #4
    The expression latent heat refers to the amount of energy released or absorbed by a chemical substance during a change of state that occurs without changing its temperature, meaning a phase transition such as the melting of ice or the boiling of water.
    I don’t know about Latent Heat of Ashes but I can tell you about Latent heat of Water. May be this could help you.
    To calculate the latent heat of condensation in water in the temperature range from −40 °C to 40 °C the following empirical cubic function can be used:
    Lwater(T) = − 0.0000614342T3 + 0.00158927T2 − 2.36418T + 2500.79
    with a determination coefficient of R2 = 0.999988
  6. Feb 26, 2010 #5


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    Ashes have a lot of surface area, since they consist of lots of small, possibly porous particles. It's not surprising that through natural convection they would cool quickly to ambient temperature.
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