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## Entropy (order and disorder)
In thermodynamics, entropy is often associated with the amount of order, disorder, and/or chaos in a thermodynamic system. This stems from Rudolf Clausius' 1862 assertion that any thermodynamic processes always "admits to being reduced to the alteration in some way or another of the In the years to follow, Ludwig Boltzmann translated these "alterations" into that of a probabilistic view of order and disorder in gas phase molecular systems. In recent years, in some chemistry publications, there has been a shift away from using the terms "order" and "disorder" to that of the concept of energy dispersion to describe entropy, among other theories. In the 2002 encyclopedia Encarta, for example Locally, the entropy can be lowered by external action. This applies to machines, such as a refrigerator, where the entropy in the cold chamber is being reduced, and to living organisms. This local decrease in entropy is, however, only possible at the expense of an entropy increase in the surroundings. ## Additional recommended knowledge
## HistoryThis "molecular ordering" entropy perspective traces its origins to molecular movement interpretations developed by Rudolf Clausius in the 1850s, particularly with his 1862 visual conception of molecular disgregation. Similarly, in 1859, after reading a paper on the diffusion of molecules by Clausius, Scottish physicist James Clerk Maxwell formulated the Maxwell distribution of molecular velocities, which gave the proportion of molecules having a certain velocity in a specific range. This was the first-ever statistical law in physics. In 1864, Ludwig Boltzmann, a young student in Vienna, came across Maxwell’s paper and was so inspired by it that he spent much of his long and distinguished life developing the subject further. Later, Boltzmann, in efforts to develop a kinetic theory for the behavior of a gas, applied the laws of probability to Maxwell's and Clausius' molecular interpretation of entropy so to begin to interpret entropy in terms of order and disorder. Similarly, in 1882 Hermann von Helmholtz used the word "Unordnung" (disorder) to describe entropy. ## OverviewTo highlight the fact that order and disorder are commonly understood to be measured in terms of entropy, below are current science encyclopedia and science dictionary definitions of entropy: **Entropy**– a measure of the unavailability of a system’s energy to do work; also a measure of disorder; the higher the entropy the greater the disorder.^{[5]}**Entropy**– a measure of disorder; the higher the entropy the greater the disorder.^{[6]}**Entropy**– in thermodynamics, a parameter representing the state of disorder of a system at the atomic, ionic, or molecular level; the greater the disorder the higher the entropy.^{[7]}**Entropy**– a measure of disorder in the universe or of the availability of the energy in a system to do work.^{[8]}
Entropy and disorder also have associations with equilibrium. In systems ecology, as another example, the entropy of a collection of items comprising a system is defined as a measure of their disorder or equivalently the relative likelihood of the instantaneous configuration of the items. The mathematical basis with respect to the association entropy has with order and disorder began, essentially, with the famous Boltzmann formula,
Thus, if entropy is associated with disorder and if the entropy of the universe is headed towards maximal entropy, then many are often puzzled as to the nature of the "ordering" process and operation of evolution in relation to Clausius' most-famous version of the second law, which states that the universe is headed towards maximal “disorder”. In the recent 2003 book The common argument used to explain this is that, locally, entropy can be lowered by external action, e.g. solar heating action, and that this applies to machines, such as a refrigerator, where the entropy in the cold chamber is being reduced, to growing crystals, and to living organisms. ## Phase changeOwing to these early developments, the typical example of entropy change Δ From his famous 1896 Thus, according to Boltzmann, owing to increases in thermal motion, whenever heat is added to a working substance, the rest position of molecules will be pushed apart, the body will expand, and this will create more ## Adiabatic demagnetizationIn the quest for ultra-cold temperatures, a temperature lowering technique called adiabatic demagnetization is used, where atomic entropy considerations are utilized which can be described in order-disorder terms. The "disorder" and hence the entropy associated with the change in the atomic alignments has clearly increased. ## See also- Entropy
- History of entropy
- Entropy (energy dispersal)
- Entropy (statistical views)
- Entropy (thermodynamic views)
## References**^***Mechanical Theory of Heat*– Nine Memoirs on the development of concept of "Entropy" by Rudolf Clausius [1850-1865]- ^
^{a}^{b}^{c}^{d}Microsoft ® Encarta ® 2006. © 1993-2005 Microsoft Corporation. All rights reserved. **^**Mahon, Basil (2003).*The Man Who Changed Everything – the Life of James Clerk Maxwell*. Hoboken, NJ: Wiley.__ISBN 0-470-86171-1__.**^**Anderson, Greg (2005).*Thermodynamics of Natural Systems*. Cambridge University Press.__ISBN 0-521-84772-9__.**^***Oxford Dictionary of Science*, 2005**^***Oxford Dictionary of Chemistry*, 2004**^**Barnes & Noble's*Essential Dictionary of Science*, 2004**^**Gribbin's*Encyclopedia of Particle Physics*, 2000**^**- ^
^{a}^{b}Greven, Andreas; Keller, Gerhard; Warnercke, Gerald (2003).*Entropy – Princeton Series in Applied Mathematics*. Princeton University Press.__ISBN 0-691-11338-6__. - ^
^{a}^{b}^{c}^{d}Ulanowicz, Robert, E. (2000).*Growth and Development – Ecosystems Phenomenology*. toExcel Press.__ISBN 0-595-00145-9__. **^**Kubat, L.; Zeman, J. (1975).*Entropy and Information in Science and Philosophy*. Elsevier.- ^
^{a}^{b}Jorgensen, Sven, J.; Svirezhev, Yuri, M.; (2004).*Towards a Thermodynamic Theory for Ecological Systems*. Elsevier.__ISBN 0-08-044167-X__. **^**Strogatz, Steven (2003).*the Emerging Science of Spontaneous Order*. Theia.__ISBN 0-7868-6844-9__.**^****^**Cercignani, Carlo (1998).*Ludwig Boltzmann - the Man Who Trusted Atoms*. Oxford University Press.__ISBN 0-19-850154-4__.**^**Boltzmann, Ludwig (1896).*Lectures on Gas Theory*. Dover (reprint).__ISBN 0-486-68455-5__.- ^
^{a}^{b}^{c}Halliday, David; Resnick, Robert (1988).*Fundamentals of Physics, Extended 3rd ed.*. Wiley.__ISBN 0-471-81995-6__. - ^
^{a}^{b}^{c}NASA - How does an Adiabatic Demagnetization Refrigerator Work ?
Categories: Thermodynamic entropy | Thermodynamics |
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This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Entropy_(order_and_disorder)". A list of authors is available in Wikipedia. |