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I Laws of thermodynamics basically establish its properties?

  1. Jun 8, 2018 #1
    Do the laws of thermodynamics basically establish its properties?

    I got to thinking, and it seems that the main purpose of the laws of thermodynamics is to establish that the thermodynamic properties.

    0th & 3rd - establish Termperature as a valid property via ability to have equality & scale, respectively

    1st - establishes Internal Energy as a property (i.e., what change results from the net influx of thermodynamic energy)

    2nd - establishes Entropy as a property, while also formally affixing a true Temperature (i.e., as per the rule that the infimum of the net change in Entropy, which is defined in part by Temperature, is 0)
     
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  3. Jun 9, 2018 #2

    Andrew Mason

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    The answer to "what came first, the laws of thermodynamics or establishing/defining thermodynamic properties" is the same as the answer to "what came first, the chicken or the egg?". The answer is (probably) "neither, they both evolved together". Thermodynamics developed from various attempts to provide a theoretical foundation to explain how heat is used to do useful mechanical work.

    The first law, and the concept of internal energy, followed from the recognition that heat flow was really a flow of energy - a concept that was poorly understood until well into the 19th century.

    The second law started out as a simple statement that spontaneous heat flow occurs only from hotter to cooler bodies. The concept of temperature is essential to this. With the development of the kinetic theory of gases, the statistical concepts behind temperature and entropy became clearer.
     
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