Agregatna stanja – razlika između verzija
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== Četiri fundamentalna stanja ==
=== Čvrsto agregatno stanje ===
[[Image:Stohrem.jpg|thumb|left|Kristalna čvrsta materija: slika atomske rezolucije [[stroncijum titanat]]a. Svetliji atomi su [[Stroncijum|Sr]] a tamniji us [[Titanijum|Ti]].]]
{{Glavni članak|Čvrsto agregatno stanje}}
Tela u čvrstom stanju mogu biti [[kristal]]na i amorfna. U kristalnim telima atomi su pravilno raspoređeni u prostoru i samo [[oscilacija|osciluju]] oko ravnotežnih položaja. U amorfnim telima čestice isto osciluju oko ravnotežnih položaja ali je njihov prostorni raspored neuređen.<ref>
{{Cite book
|author=M.A. Wahab
|date=2005
|title=Solid State Physics: Structure and Properties of Materials
|publisher=Alpha Science
|pages=1–3
|isbn=1-84265-218-4
}}</ref>
[[Glass]]es and other non-crystalline, [[amorphous solid]]s without [[order and disorder (physics)|long-range order]] are not [[thermal equilibrium]] ground states; therefore they are described below as nonclassical states of matter.
Solids can be transformed into liquids by melting, and liquids can be transformed into solids by freezing. Solids can also change directly into gases through the process of [[sublimation (chemistry)|sublimation]], and gases can likewise change directly into solids through [[deposition (phase transition)|deposition]].
=== Tečno agregatno stanje ===
[[Image:Teilchenmodell Flüssigkeit.svg|thumb|left|Struktura klasične monoatomske tečnosti. Atomi imaju mnoge bliske susede, mada ne postoji pravilan raspored na većim razdaljinama.]]
{{Glavni članak|tečnost}}
U tečnom stanju raspored čestica je poput onoga u amorfnom s time što je dopušteno i [[translatorno kretanje]] čestica. Dakle, pored oscilovanja oko ravnotežnih položaja čestice se međusobno kreću. (Molekuli mogu još i da [[rotacija|rotiraju]] oko svog [[centar mase|centra mase]] i još da poseduju brojne oblike unutrašnjeg kretanja poput vibracija, torzionih oscilacija, rotacija, konformacionih prelaza itd.) Pri tome čestice mogu da razmenjuju položaje i da stvaraju nove, međutim, privlačne sile su dovoljno velike u odnosu na termalnu energiju da drže čestice na bliskim rastojanjima. Otuda tečnosti imaju konstantnu zapreminu ali ne i oblik.<ref name=White>
{{Cite book
|author=F. White
|date=2003
|title=Fluid Mechanics
|page=4
|publisher= McGraw-Hill
|isbn=0-07-240217-2
}}</ref>
=== Gasovito agregatno stanje ===
{{glavni|Gas}}
U gasovitom stanju privlačne sile među česticama znatno su slabije od njihove toplotne energije pa se čestice skoro slobodno kreću ispunjavajući celokupan raspoloživi prostor.<ref name=Turrell>
{{Cite book
|author=G. Turrell
|date=1997
|title=Gas Dynamics: Theory and Applications
|url=http://books.google.com/?id=-6qF7TKfiNIC&pg=PA3
|publisher= John Wiley & Sons
|pages=3–5
|isbn=0-471-97573-7
}}</ref>
=== Plazma ===
Linija 27 ⟶ 60:
== Promena agregatnog stanja ==
{{wide image|Physics matter state transition 1 en.svg|800px|This diagram illustrates transitions between the four fundamental states of matter.}}▼
{{glavni|Fazna transformacija}}
▲{{wide image|Physics matter state transition 1 en.svg|800px|This diagram illustrates transitions between the four fundamental states of matter.}}
Prelaz iz jednog agregatnog stanja u drugo naziva se [[fazni prelaz]]. Pri tome se menja samo relativni raspored čestica i/ili njihova pokretljivost ali ne i njihova hemijska priroda. Dakle, promena agregatnog stanja je striktno fizički proces bez hemijskih reakcija. Promena agregatnog stanja može da bude skokovita (topljenje leda, sublimacija joda, isparavanje vode) ili kontinualna (omekšavanje stakla). Na temperaturi [[apsolutna nula|apsolutne nule]] skoro sve supstance su u čvrstom stanju. Na ekstremno visokim temperaturama skoro sve supstance prelaze u plazmu. <ref>
Linija 45 ⟶ 78:
|date=1985
|title=States of Matter
|publisher=
|isbn=978-0-486-49506-4
}}</ref><ref>
Linija 154 ⟶ 187:
|title=Strange but True: Superfluid Helium Can Climb Walls
|url=http://www.scientificamerican.com/article.cfm?id=superfluid-can-climb-walls
|work=
|accessdate=23 February 2010
}}</ref> It also has infinite [[thermal conductivity]] so that no [[temperature gradient]] can form in a superfluid. Placing a superfluid in a spinning container will result in [[quantum vortex|quantized vortices]].
Linija 248 ⟶ 281:
|date=1997
|title=Superfluids and Supersolids on Frustrated Two-Dimensional Lattices
|journal=
|volume=55
|issue=5 |page=3104
Linija 264 ⟶ 297:
===Dark matter===
{{Main|Dark matter}}
While dark matter is estimated to comprise 83% of the mass of matter in the [[universe]], most of its properties remain a mystery due to the fact that it neither [[Absorption (electromagnetic radiation)|absorbs]] nor [[Emission spectrum|emits]] [[electromagnetic radiation]], and there are many competing theories regarding what dark matter is actually made of. Thus, while it is hypothesized to exist and comprise the vast majority of matter in the universe, almost all of its properties are unknown and a matter of speculation, because it has only been observed through its [[gravitation]]al effects.<ref name="Trimble 1987" >{{cite journal | authorlink=
|last = Hinshaw
|first = Gary F.
| |||