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Nova strana: {{Prijevod}} U fizikalnoj hemiji, mineralogiji i nauci o materijalima, '''fazni dijagram''' je vrsta [[Grafik funkcije|gra...
 
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U [[Fizikalna hemija|fizikalnoj hemiji]], [[mineralogija|mineralogiji]] i [[nauka o materijalima|nauci o materijalima]], '''fazni dijagram''' je vrsta [[Grafik funkcije|grafik]] koji pokazuje [[termodinamička jednačina|jednačinu]] uvijeta između termodinamički različitih [[Faza (materija)|faza]]. U [[matematika|matematici]] i [[fizika|fizici]], fazni dijagram ima drugu značenje kao sinonim za [[fazni prostor]].
 
== Dijagrami pritisak-temperatura ==
==Pressure-temperature diagrams==
 
Najjednostavniji fazni dijagrami su dijagrami pritisak-temperatura jedne jednostavne substance, kao što je [[voda]]. [[Apscisa]] i [[ordinata]] odgovaraju [[pritisak|pritisku]] i [[temperatura|temperaturi]]. Fazni dijagram pokazuje, u prostoru pritisak-temperatura, linije ravnoteže ili fazne granice između tri faze: [[čvrsta faza|čvrste]], [[tečna faza|tečne]] i [[gasovita faza|gasovite]].
The simplest phase diagrams are pressure-temperature diagrams of a single simple substance, such as [[water (molecule) | water]]. The [[axes]] correspond to the [[pressure]] and [[temperature]]. The phase diagram shows, in pressure-temperature space, the lines of equilibrium or phase boundaries between the three phases of [[solid]], [[liquid]], and [[gas]].
 
[[Slika:Phase-diag.svg|thumb|300px|ATipični typicalfazni phase diagramdijagram. TheLinija, dottedoznačena linetačkama, givespokazuje theanomalijsko anomalousponašanje behaviour of watervode. Zelena Thelinija green lines mark theoznačavaju [[freezingtačka pointsmrzavanja|tačku smrzavanja]], anda theplava blue line thelinija [[boilingtačka pointključanja|tačku ključanja]], showingte pokazuju kako howse theyone varymijenjaju withsa pressurepritiskom.]]
 
Oznake na faznom dijagramu pokazuju gdje je slobodnu energiju nemoguće odrediti. Otvoreni prostori, gdje je [[slobodna enrgija|slobodnu enrgiju]] moguće [[analitička funkcija|izračunati]], odgovaraju fazama. Faze su odvojene linijama neodređene energije gdje se [[fazni prijelaz]]i odvijaju, koje se zovu '''granice faza'''.
The markings on the phase diagram show the points where the free energy is non-analytic. The open spaces, where the [[free energy]] is [[analytic function|analytic]], correspond to the phases. The phases are separated by lines of non-analyticity, where [[phase transition]]s occur, which are called '''phase boundaries'''.
 
In the diagram, the phase boundary between liquid and gas does not continue indefinitely. Instead, it terminates at a point on the phase diagram called the [[critical point (chemistry)|critical point]]. This reflects the fact that, at extremely high temperatures and pressures, the liquid and gaseous phases become indistinguishable, in what is known as a [[supercritical fluid]]. In water, the critical point occurs at around 647 [[Kelvin|K]] (374 °C or 705 °F) and 22.064 [[Pascal (unit)|MPa]].
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An interesting thing to note is that the solid-liquid phase boundary in the phase diagram of most substances, such as the one shown above, has a positive [[slope]]. This is due to the solid phase having a higher [[density]] than the liquid, so that increasing the pressure increases the melting temperature. However, in the phase diagram for water the solid-liquid phase boundary has a negative slope. This reflects the fact that ice has a lower density than water, which is an unusual property for a material.
 
== Binarni fazni dijagrami ==
==Binary phase diagrams==
 
Ostale, mongo komplikovanije vrste faznih dijagrama, mogu se konstruisati, pogotovo kada je prisutno više od jedne čiste komponente. U ovom slučaju, [[koncentracija]] postaje veoma bitna varijabla. Fazni dijagrami, sa više od dvije dimenzije, mogu se konstruisati kako bi se pokazao uticaj više od dvije varijable na fazu substance. Fazni dijagrami mogu koristit i druge varijable kao nadopunu ili kao zamijenu za temperaturu, pritisak i sastav (npr. jačina eletričnog ili magnetnog polja), kao i substance koje uzimju više od tri stanja materije.
Other, much more complex types of phase diagrams can be constructed, particularly when more than one pure component is present. In that case [[concentration]] becomes an important variable. Phase diagrams with more than two dimensions can be constructed that show the effect of more than two variables on the phase of a substance. Phase diagrams can use other variables in addition to or in place of temperature and pressure and composition, for example the strength of an applied electrical or magnetic field and they can also involve substances that take on more than just three states of matter.
 
[[Slika:Eutektikum.gif|thumb|300px|AFazni phasedijagram diagrambinarnog forsistema, akoji binarypokazuju systemeutektičku displaying a eutectic pointtačku.]]
 
One type of phase diagram plots temperature against the relative concentrations of two substances in a [[Wiktionary:binary|binary]] [[mixture]] called a '''binary phase diagram'''. Such a mixture can be either a [[solid solution]], [[eutectic point|eutectic]] or [[peritectic]], among others. These two types of mixtures result in very different graphs. A textbook example of a eutectic phase diagram is that of the [[olivine]] ([[forsterite]] and [[fayalite]]) system.
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The x-axis of such a diagram represents the [[concentration]] variable of the mixture. As the mixtures are typically far from dilute and their density as a function of temperature usually unknown the preferred concentration measure is [[mole fraction]]. A volume based measure like [[molarity]] would be unadvisable.
 
== Uobičajne komponente faznog dijgrama ==
==Common components of a phase diagram==
 
'''Linije ravnoteže''' ili '''fazne granice''' odnose se na linije koje pokazuju gdje se odvijaju fazni prijelazi.
'''Lines of equilibrium''' or '''phase boundaries''' refer to the lines that demarcate where phase transitions occur.
 
[[Trostruka tačka]] je, u faznom dijagramu pritisak-temperatura, jednistveno prosjecište linija [[termodinamička ravnoteža|ravnoteže]] između tri stanja materije, najčeće čvrste, tečne i gaovite faze.
A [[triple point]] is, in a pressure-temperature phase diagram, the unique intersection of the lines of [[thermodynamic equilibrium|equilibrium]] between three states of matter, usually solid, liquid, and gas.
 
Za fazne dijagrame sa temperaturom na ordinati, [[solidus linija]] je linija ispod koje je substanca stabilna u čvrstom stanju. [[Likvidus linija]] je linija iznad koje je substanca stabilna u tečnom stanju. Između solidus i likvidus linija može se nalaziti praznina; unutar praznine substanca se sastoji od čvrstih kristala i tečnosti.
For a phase diagram with temperature on the vertical axis, a [[solidus (chemistry)|solidus]] is a line below which the substance is stable in the solid state. A [[liquidus]] is a line above which the substance is stable in a liquid state. There may be a gap between the solidus and liquidus; within the gap, the substance is replaced by a mixture of solid crystals and liquid.
 
== Fazni dijagram tečnih kristala ==
==Liquid crystal phase diagrams==
 
U fizici [[tečni kristal|tečnih kristala]], fazni dijagrami se koriste u slučaju miješanja nematogeničnih komponenti, kako bi se uspostavila razlika između [[izotrop]]ne i nematiče tečne faze.
In [[liquid crystal]] physics, phase diagrams are used in the case of mixing of nematogenic compounds to distinguish between the [[isotropic]] liquid phase, the [[nematic]] liquid phase.
 
== Također pogledajtpogledajte ==
 
* [[Gibbsovo pravilo faze]]
Preuzeto iz "https://bs.wikipedia.org/wiki/Fazni_dijagram"