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What determines the specific heat capacity of a given substance?

  1. Sep 1, 2010 #1
    I'm fascinated with physics and probably know at least the nature of any effect or object in classical physics, but um... I have never in any textbook or article seen mention of what determines the specific heat capacity of a given substance. Which is kinda peculiar and confusing at the same time.

    It is also the question of this thread:
    What determines the specific heat capacity of a given substance?
     
  2. jcsd
  3. Sep 1, 2010 #2

    marcusl

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    Last edited by a moderator: Apr 25, 2017
  4. Sep 2, 2010 #3
    What I dearly LOVE about water is its extremely high heat capacity, particularly when changing phases.

    Heating a gram of water one degree Celsius requires a calorie of energy.
    However one calorie of energy heats a gram of gold about 30 degrees Celsius.

    As significant as the heat capacity of water is, it pales in comparison to the heat
    capacity of ice, which is 80 times as great, and that doesn't even raise the temperature.
    It only MELTS it at constant temperature.

    Okay, okay, here is where it gets nerdly cool, if you know what I mean.

    Adding energy to water at its boiling point to make steam takes a BUNCH of ergs - 540 times as many as heating water up.

    The implications are that if you want to cool off on a hot day, do NOT wipe off your brow.
    And if you don't want to get burned very badly, keep your distance from steam.
    Sticking your finger into boiling hot water wouldn't be nearly as injurious as being the condenser for steam.

    Experiment: What is the equilibrium temperature after adding one pound of ice at 0 degrees Celsius to one pound of water at 100 degrees Celsius in a perfectly insulated container?

    How about adding that same pound of ice to a pound of steam at 100 degrees?
     
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