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#1
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| Asked to my sister on a chemistry test was the usual: Which of the following represent an increase in the entropy of the substance (more than one may need to picked): a. Melting ice. b. Sublimating Carbon Dioxide c. Spilling milk onto a table d. ... Now, when she asked the question to me, I said that A and B were both representative of increasing entropy, as had she. BUT, according to her teacher, spilling milk onto a table increases the entropy. Are we going crazy? How does that increase the entropy (I suppose in a very loose sense it does increase the amount of disorder in the universe.) --- bollod |
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#2
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| "bollod" <bollod@lycos.com> wrote in message news I doubt whether spilling milk onto a table has a significant effect on the disorder of the universe as a whole, but it certainly has increased the disorder of the milk! (I'm sure the person who had to mop up the milk would agree) It's a very simplistic way of looking at it, of course. Barry Hunt |
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#3
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| in article [Only registered users see links. ], bollod at [Only registered users see links. ] wrote on 12/9/03 1:53 PM: Most of the entropy in a liquid arises from the motion of the individual particles, molecules if you will. If you spill the liquid, entropy will indeed increase but only by a small amout. Consider a bucket of BBs. If you spill them onto a table, the entropy (disorder) will increase. The entropy in each BB because of disorder of the molecular motions will be much greater than the disorder from a few macromolecules (BBs) bouncing around randomly. Bill |
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#4
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#5
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| Systemic science would see spilling milk onto a table a manifestation of entropy by opposition to negentropy. Negentropy is the force that build up things and elaborate specificity, structure. Entropy is the force that destroys things down and create homogeneity, chaos. Milk in a glass is more structured, compacted than milk on a table (big surface vs volume). Solid ice is formed of cristals wich by definition is a molecular building where water molecules are almost "freezed" in place...when ice melts (consuming external energy-pressure or temperature) it reduces its volume (so volumetrically speaking entropy decreases a little-in most substance solid state is denser than liquid state wich is itself denser than gaseous state; so there is normaly an inverse relation between density and entropy) but since all the molecules wich were fixed are now able to break their interaction, they gain 3D freedom lability and the entropy of the system increases a lot. CO2 follows the normal inverse law of density / entropy; So entropy goes up when going from Dry ice --> liquid CO2 --> gaseous CO2 while density goes down! And here you have also the phase change as in water case; so each CO2 molecule gain a few freedom levels vs when it is in iced form. Remark: In some case spilling a liquid on a surface will increase its order...it is the case of fatty acids on water; at an extreme extension of the surface/volume you get ordered molecular layers as the one you find in cellular organisms (lipidic bilayer) or in liposoms...then molecular orientation is no more isotropic but has become anisotropic. Ph Z David Bolton wrote: |
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#6
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| LOUIS wrote: "freezed" Frozen, sorry! |
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| entropy , increase , liquid , question , spilling , substance |
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| Thread | Thread Starter | Forum | Replies | Last Post |
| Question re Entropy | Walter R. | Physics Forum | 3 | 02-19-2006 01:36 AM |