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Water vapor condenses into a liquid after making contact with the surface of a cold bottle.

Condensation forming over the wing of an aircraft in a low pressure zone

Condensation is the change of the physical state of matter from gaseous phase into liquid phase, and is the reverse of vaporization.^[1] When the transition happens from the gaseous phase into the solid phase directly, the change is called deposition.

Initiation[edit]

Condensation is initiated by the formation of atomic/molecular clusters of that species within its gaseous volume—like rain drop or snow-flake formation within clouds—or at the contact between such gaseous phase and a (solvent) liquid or solid surface.

Reversibility scenarios[edit]

A few distinct reversibility scenarios emerge here with respect to the nature of the surface.

• absorption into the surface of a liquid (either of the same substance or one of its solvents)—is reversible as evaporation.^[1]
• adsorption (as dew droplets) onto solid surface at pressures and temperatures higher than the species' triple point—also reversible as evaporation.
• adsorption onto solid surface (as supplemental layers of solid) at pressures and temperatures lower than the specie's triple point—is reversible as sublimation.

Most common scenarios[edit]

Condensation commonly occurs when a vapor is cooled and/or compressed to its saturation limit when the molecular density in the gas phase reaches its maximal threshold. Vapor cooling and compressing equipment that collects condensed liquids is called a "condenser".

How condensation is measured[edit]

Psychrometry measures the rates of condensation from and evaporation into the air moisture at various atmospheric pressures and temperatures. Water is the product of its vapor condensation—condensation is the process of such phase conversion.

Applications of condensation[edit]

Condensation is a crucial component of distillation, an important laboratory and industrial chemistry application.

Because condensation is a naturally occurring phenomenon, it can often be used to generate water in large quantities for human use. Many structures are made solely for the purpose of collecting water from condensation, such as air wells and fog fences. Such systems can often be used to retain soil moisture in areas where active desertification is occurring—so much so that some organizations educate people living in affected areas about water condensers to help them deal effectively with the situation.^[2]

It is also a crucial process in forming particle tracks in a cloud chamber. In this case, ions produced by an incident particle act as nucleation centers for the condensation of the vapor producing the visible "cloud" trails.

Biological adaptation[edit]

Numerous living beings use water made accessible by condensation. A few examples of these are the Australian Thorny Devil, the darkling beetles of the Namibian coast, and the Coast Redwoods of the West Coast of the United States.

Condensation in building construction[edit]

Condensation on a window during a rain shower.

Condensation in building construction is an unwanted phenomenon as it may cause dampness, mold health issues, wood rot, corrosion and energy loss due to increased heat transfer. To alleviate these issues the air ventilation in the building needs to be improved. This can be done in a number of ways; opening windows, turning on extractor fans, drying clothes outside and covering pots and pans whilst cooking to name a few. Air ventilation systems can be installed that help move air throughout a building.^[3]

Interstructure condensation may be caused by thermal bridges, insufficient or lacking damp proofing or insulated glazing.^[4]

See also[edit]

• Air well (condenser)
• Bose–Einstein condensate
• Condenser (heat transfer)
• DNA condensation
• Kelvin equation
• Phase diagram
• Phase transition
• Retrograde condensation
• Surface condenser
• Groasis Waterboxx

References[edit]

References[edit]

• "Condensation principles (Picture)". 

v t e States of matter (classic) State Solid Liquid Gas / Vapor Plasma Low energy Bose–Einstein condensate Fermionic condensate Degenerate matter Quantum Hall Rydberg matter Strange matter Superfluid Supersolid High energy QCD matter Quark–gluon plasma Supercritical fluid Other states Colloid Glass Liquid crystal Magnetically ordered Antiferromagnet Ferrimagnet Ferromagnet String-net liquid Superglass Transitions Boiling Boiling point Condensation Critical line Critical point Crystallization Deposition Evaporation Flash evaporation Freezing Ionization Lambda point Melting Melting point Recombination Regelation Saturated fluid Sublimation Supercooling Triple point Vaporization Vitrification Quantities Enthalpy of fusion Enthalpy of sublimation Enthalpy of vaporization Latent heat Latent internal energy Trouton's ratio Volatility Concepts Binodal Compressed fluid Cooling curve Equation of state Leidenfrost effect Mpemba effect Order and disorder (physics) Spinodal Superconductivity Superheated vapor Superheating Thermo-dielectric effect Lists List of states of matter