What Is Entropy, REALLY?
Entropy measures the spontaneous dispersal of energy: how much energy is spread out in a process, or how widely spread out it becomes — at a specific temperature. (Sometimes, its a simple equation, Entropy change = energy dispersed/T, or qreversible/T , as in phase changes like melting or vaporization where ΔS = ΔHfusion /T or ΔHvaporization /T, respectively.) (In chemistry the energy that entropy measures as dispersing is motional energy, the translational and vibrational and rotational energy of molecules [Figure 1 of http://www.2ndlaw.com/entropy.html ] and the ΔH of phase change energy — both motional or phase change energy being designated either as “q” or ΔH in many equations. Bond energy, the potential energy associated with chemical bonds that we talked about in the iron oxidation example, is only measured by entropy change in connection with a chemical reaction in ΔG = ΔH – T ΔS Is that description of an entropy change complicated? Entropy is a sophisticated kind of “before an
