We explain what reverse sublimation is, under what conditions it occurs and various examples. Also, what is progressive sublimation.
Snow is the sublimation of water vapor to a solid state.What is reverse sublimation?
It is known as deposition, desublimation, reverse sublimation or back sublimation to process phase shift or state of matter aggregation according to which a substance in gaseous state go directly to solid state, without going through it first liquid state.
This is a thermodynamic process of the typeexothermic, that is, that freesEnergy. This is the exact opposite of sublimation.
Thesublimation, whether inverse or not, is a phenomenon ofnature to which any pure substance. This requires conditions oftemperature Y Pressure very specific, which is why it is not often observed with the naked eye, but in laboratories or in particular environments such as Antarctica, the summit of themoutains snowfall, etc.
Examples of reverse sublimation
Some examples of reverse sublimation are:
- The transformation of water steam atmospheric directly on ice, in the polar or circumpolar regions, because the cold prevents the formation of Water liquid first.
- The deposition of snow or frost on frozen moorlands and mountain peaks, as the temperature in the atmosphere it is such that the rainwater does not have time to become liquid.
- The formation of dry ice in laboratories, which is carried out by freezing CO2 and subjecting it to enormous pressure.
- According to current cosmological theories, solid planets would have been formed by planetary accretion from gases, which is more or less a form of reverse sublimation.
Progressive sublimation
The term progressive sublimation is the exact and complete term of the sublimation, that is, they are synonyms. The addition "progressive" is used to differentiate it from regressive, according to the terms "forward" (progressive) or "backward" (regressive).
Progressive sublimation will be the phase change process of the matter in which a solid becomes a gaseous state, without first passing through the liquid state. This occurs with certain forms of ice (such as dry ice made from CO2, constantly broadcasting steam) or in places so cold and dry that liquid water is impossible.