Thermodynamics is the connection between heat and work in the universe and the conversion of one to another. There is so much information on this topic that it would be hard for me to elaborate on just one aspect of it, so I have decided to touch upon those basic subjects most relating to our everyday lives. When my research began I believed that this would mean spending most of my time on the First Law of Thermodynamics, but little did I know that it is the Second Law, with its relation to entropy, that most affects us.
In the days long gone, the Second Law of Thermodynamics-which predates the first law-was regarded as perhaps the most perfect and irrefutable law in all of science. It is used to calculate entropy, specific and latent heats, and transition properties, often with good accuracy. Important examples of this would be Planck's realization when staring into a furnace that he could find Avogadro's number, and Linus Pauling's highly accurate "back of an envelope" calculation of the residual entropy of ice. The law, theorized in the early 1800's by Nicolas Leonard Sadi Carnot and later refined by Ludwig Boltzman, states that in any spontaneous process the entropy of the universe increases as its reverse reaction happens as a result in the opposite direction. Still to this day not even the littlest exception to the law has been found. Albert Einstein put it best when referring to the second law in this way:.
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A theory is the more impressive the greater the simplicity of its premises, the more different kinds of things it relates, and the more extended its area of applicability. Therefore the deep impression in which classical thermodynamics made upon me. It is the only physical theory of universal content concerning which I am convinced that, within the framework of the applicability of its basic concepts; it will never be overthrown.
Problems pertaining to the second law require the measurement of H to both the system and the surroundings, whether that system is either infinite or isolated.