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> I think the thermodynamic law throws everyone off. Entropy is not the axiomatic law. The law is probability, Yes, and I think the other big plunder often com

> I think the thermodynamic law throws everyone off. Entropy is not the axiomatic law. The law is probability, Yes, and I think the other big plunder often committed is explaining entropy in thermodynamics as a measure for "disorderliness". You might get away with that if you want to explain diffusion processes to a class of high school students, but even then the idea quickly falls flat on it's face once they realize that in chemistry things crystalize out, often after giving off thermal energy. (Also, "disorderliness" is a fairly subjective concept)

not2b 6y ago
No, that doesn't follow: entropy can decrease provided that it is exothermic enough. For a spontaneous reaction to occur, the relevant quantity isn't the entropy, but the Gibbs free energy. So reactions that reduce entropy (because "things crystalize out") can take place if the enthalpy increases enough to compensate.
neonological 6y ago
A system of loaded dice is a good counter example to "disorder". 10 loaded Dice weighted to always roll 6 trends towards our definition of order because 6 is simply more likely to occur. In this case rolling 10 dice increases order but that order represents increasing entropy.
- jkhdigital 6y ago
  I think a more suitable pair of common antonyms is “predictability” and “unpredictability”.
  - neonological 6y ago
    Some systems can be configured where such that only one possible outcome is possible. In that case your prediction rate would be 100%. So for example the loaded dice are programmed to always roll a 6. Thus the most predictable and ordered outcome (all 6s) is also the highest entropy state. Entropy simply says that over time the configuration of certain entities within a system will progress towards higher probability configurations. For most systems (like for example, non-loaded dice) the most probable outcome is a disordered state. But this is not the case for all systems. Take our solar system for example. The most probable outcome for the configurations of all particles orbiting our sun is to form perfect spheres (planets). This is the highest entropy state of the system. The system by itself naturally progresses towards spherical configurations that we can only describe as ordered. However, when people talk about entropy in terms of heat. Entropy is indeed in this case measuring disorder. But this is a very specific definition of entropy for one type of system and the more general definitions are the ones provided by information theory and statistical mechanics.

not2b 6y ago

No, that doesn't follow: entropy can decrease provided that it is exothermic enough. For a spontaneous reaction to occur, the relevant quantity isn't the entropy, but the Gibbs free energy. So reactions that reduce entropy (because "things crystalize out") can take place if the enthalpy increases enough to compensate.

neonological 6y ago

A system of loaded dice is a good counter example to "disorder". 10 loaded Dice weighted to always roll 6 trends towards our definition of order because 6 is simply more likely to occur. In this case rolling 10 dice increases order but that order represents increasing entropy.

jkhdigital 6y ago
I think a more suitable pair of common antonyms is “predictability” and “unpredictability”.
- neonological 6y ago
  Some systems can be configured where such that only one possible outcome is possible. In that case your prediction rate would be 100%. So for example the loaded dice are programmed to always roll a 6. Thus the most predictable and ordered outcome (all 6s) is also the highest entropy state. Entropy simply says that over time the configuration of certain entities within a system will progress towards higher probability configurations. For most systems (like for example, non-loaded dice) the most probable outcome is a disordered state. But this is not the case for all systems. Take our solar system for example. The most probable outcome for the configurations of all particles orbiting our sun is to form perfect spheres (planets). This is the highest entropy state of the system. The system by itself naturally progresses towards spherical configurations that we can only describe as ordered. However, when people talk about entropy in terms of heat. Entropy is indeed in this case measuring disorder. But this is a very specific definition of entropy for one type of system and the more general definitions are the ones provided by information theory and statistical mechanics.