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The reverse process of sublimation is deposition (also called desublimation), in which a substance passes directly from a gas to a solid phase, without passing through the liquid state. [4] Technically, all solids may sublime, though most sublime at extremely low rates that are hardly detectable under usual conditions.
Sublimation is the process of changing of any substance (usually on heating) from a solid to a gas (or from gas to a solid) without passing through liquid phase. In terms of purification - material is heated, often under vacuum, and the vapors of the material are then condensed back to a solid on a cooler surface.
For a liquid–gas transition, is the molar latent heat (or molar enthalpy) of vaporization; for a solid–gas transition, is the molar latent heat of sublimation. If the latent heat is known, then knowledge of one point on the coexistence curve , for instance (1 bar, 373 K) for water, determines the rest of the curve.
At pressures below 5.13 atm and temperatures below −56.4 °C (216.8 K; −69.5 °F) (the triple point), CO 2 changes from a solid to a gas with no intervening liquid form, through a process called sublimation. [a] The opposite process is called deposition, where CO 2 changes from the gas to solid phase (dry ice). At atmospheric pressure ...
The same process, but beginning with a solid instead of a liquid is called a eutectoid transformation. A peritectic transformation, in which a two-component single-phase solid is heated and transforms into a solid phase and a liquid phase. A peritectoid reaction is a peritectoid reaction, except involving only solid phases.
Many elements and some compounds change from solids to liquids and from liquids to gases when heated and the reverse when cooled. Some substances such as iodine and carbon dioxide go directly from solid to gas in a process called sublimation.
Outgassing (sometimes called offgassing, particularly when in reference to indoor air quality) is the release of a gas that was dissolved, trapped, frozen, or absorbed in some material. [1] Outgassing can include sublimation and evaporation (which are phase transitions of a substance into a gas), as well as desorption , seepage from cracks or ...
This process is called boiling. If the boiling liquid is heated more strongly the temperature does not rise but the liquid boils more quickly. This distinction is exclusive to the liquid-to-gas transition; any transition directly from solid to gas is always referred to as sublimation regardless of whether it is at its boiling point or not.