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    What exactly is temperature? I don't mean something that allows us to feel hot or cold, but what it actually is.
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    I'd just say its thermal energy really that transfers to other particles, and the higher the temp, the more energy there is i guess

    I don't know though, Chemistry isn't my strongest of my subjects (well 2nd it is lol)
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    Wikipedia looks like it can answer your question. Just search for temperature on the site.
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    Average kinetic energy of the particles as far as i'm aware.
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    Temperature is a measure of the average kinetic energy of the particles in a substance.
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    Temperature is kinetic energy in disguise :shifty: .

    For a solid this is just increased vibrational motion. The thermal motion of atoms is very fast.

    However, I think you may be confused as to how we can give a scale to the kinetic energy of a molecule - I certainly know that my thermometer isn't reading as Joules!

    The Ideal Gas law was found to be:

    PV = NkT. There was a clear relation between the temperature and other observable characteristics.

    Consider a particle in a box moving back and forth along the x axis:

    Change in momentum 2mv
    Time between collisions 2x/v


    Force on wall = rate of change of momentum:

    =(mv^2)/x

    Pressure on wall = Force/area

    (mv^2)/xyz = P

    For N molecules: PV = (Nmv^2)/3 (3 allows for all degrees of freedom).


    Replace v^2 with vbar^2 - vbar is the root mean square of the velocities. (v=vbar from now on).

    But we know PV = NkT = (Nmv^2)/3

    N(mv^2)/2 = 3/2NkT

    Mean thermal energy is of one molecule is 3/2kT. It is clear that temperature is just the average kinetic nergy of molecules.
 
 
 
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