Sublimation (phase transition): Difference between revisions

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(top left of solid in phase diagram)
These three cases jointly exhaust the solid space in the phrase diagram. This makes sense, after all, technically, all solids sublime (depending mostly on vapour pressure, which is very situational).
One may notice there is a fourth case in the solid space, that is, at the solid-liquid boundary. It is uncertain if the solid is still defined as subliming WHILE melting, and in case it is, it would be subliming graduallyrapidly.
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The reverse process of sublimation is [[deposition (phase transition)|''deposition'']] (also called ''desublimation''), in which a substance passes directly from a gas to a solid phase, without passing through the liquid state.<ref name="DepositionDef">{{cite journal |title=Controlling condensation and frost growth with chemical micropatterns |first1=Jonathan B. |last1=Boreyko |first2=Ryan R. |last2=Hansen |first3=Kevin R. |last3=Murphy |first4=Saurabh |last4=Nath |first5=Scott T. |last5=Retterer |first6=C. Patrick |last6=Collier |journal=Scientific Reports |year=2016 |volume=6 |pages=19131 |doi=10.1038/srep19131 |pmid=26796663 |pmc=4726256 |bibcode=2016NatSR...619131B}}</ref>
 
AllTechnically, all solids may sublime, though most sublime at extremely low rates under usual conditions that are hardly detectable. At [[standard conditions for temperature and pressure|normal pressures]], most [[chemical compound]]s and [[chemical element|elements]] possess three different states at different [[temperature]]s. In these cases, the transition from the [[solid]] to the [[gas]] state requires an intermediate liquid state. The pressure referred to is the ''[[partial pressure|partial]]'' [[partial pressure|pressure]] of the substance, not the ''total'' (e.g. atmospheric) pressure of the entire system. Thus, any solid can sublime if its [[vapour pressure]] is higher than the surrounding partial pressure of the same substance, and in some cases, sublimes at an appreciable rate (e.g. water ice just below 0&nbsp;°C).
 
For some substances, such as [[carbon]] and [[arsenic]], sublimation from solid state is much more achievable than [[evaporation]] from liquid state and it is difficult to obtain them as liquids. This is because the pressure of their [[triple point]] in its [[phase diagram]] (which corresponds to the lowest pressure at which the substance can exist as a liquid) is very high.
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[[File:Camphor sublimation 1.jpg|thumb|upright|[[Camphor]] subliming in a [[cold finger]]. The crude product in the bottom is dark brown; the white purified product on the bottom of the cold finger above is hard to see against the light background.]]
 
At [[Arsenicatmospheric pressure]], [[arsenic]] sublimes gradually upon heating at [[atmospheric pressure]], and sublimes rapidly at {{convert|887|K|C}}.<ref name="Holl3">{{cite book |last=Holleman |first=Arnold F. |title=Lehrbuch der Anorganischen Chemie |author2=Wiberg, Egon |author3=Wiberg, Nils |date=1985 |publisher=Walter de Gruyter |isbn=978-3-11-007511-3 |edition=91–100 |pages=675–681 |language=de |chapter=Arsen}}</ref>
 
[[Cadmium]] and [[zinc]] sublime much more than other common materials, so they are not suitable [[materials for use in vacuum]].{{citation needed|date=May 2019}}