Condensation is the change of the physical state of matter from gas
phase into liquid phase, and is the reverse of vapourisation. The word
most often refers to the water cycle. It can also be defined as the
change in the state of water vapour to liquid water when in contact
with a liquid or solid surface or cloud condensation nuclei within the
atmosphere. When the transition happens from the gaseous phase into
the solid phase directly, the change is called deposition (or
desublimation, see Sublimation (phase transition).
2 Reversibility scenarios
3 Most common scenarios
4 How condensation is measured
5 Applications of condensation
6 Biological adaptation
Condensation in building construction
8 See also
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 liquid or solid surface.
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.
adsorption (as dew droplets) onto solid surface at pressures and
temperatures higher than the species' triple point—also reversible
adsorption onto solid surface (as supplemental layers of solid) at
pressures and temperatures lower than the species' triple point—is
reversible as sublimation.
Most common scenarios
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
Psychrometry measures the rates of condensation through 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
In cloud chambers a liquid (sometimes water, but usually isopropanol)
condenses upon contact with a particle of radiation thus producing an
effect similar to contrails
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.
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.
Furthermore, condensation is a critical step in many industrial
processes, such as power generation, water desalination, thermal
management, refrigeration, and air conditioning.
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
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, weakening
of mortar and masonry walls, and energy penalties due to increased
heat transfer. To alleviate these issues, the indoor air humidity
needs to be lowered, or air ventilation in the building needs to be
improved. This can be done in a number of ways, for example opening
windows, turning on extractor fans, using dehumidifiers, drying
clothes outside and covering pots and pans whilst cooking. Air
conditioning or ventilation systems can be installed that help remove
moisture from the air, and move air throughout a building. The
amount of water vapour that can be stored in the air can be increased
simply by increasing the temperature. However, this can be a double
edged sword as most condensation in the home occurs when warm,
moisture heavy air comes into contact with a cool surface. As the air
is cooled, it can no longer hold as much water vapour. This leads to
deposition of water on the cool surface. This is very apparent when
central heating is used in combination with single glazed windows in
Interstructure condensation may be caused by thermal bridges,
insufficient or lacking insulation, damp proofing or insulated
Air well (condenser)
Condenser (heat transfer)
Liquefaction of gases
^ a b IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold
Book") (1997). Online corrected version: (2006–) "condensation
in atmospheric chemistry".
^ FogQuest - Fog Collection / Water Harvesting Projects - Welcome
Archived 2009-02-23 at the Wayback Machine.
^ Warsinger, David M.; Mistry, Karan H.; Nayar, Kishor G.; Chung,
Hyung Won; Lienhard V, John H. (2015). "Entropy Generation of
Desalination Powered by Variable Temperature Waste Heat". Entropy.
pp. 7530–7566. Bibcode:2015Entrp..17.7530W.
doi:10.3390/e17117530. Missing or empty url= (help)
^ White, F.M. ‘Heat and Mass Transfer’ © 1988 Addison-Wesley
Publishing Co. pp. 602–604
^ Q&A: Microchannel air-cooled condenser; Heatcraft Worldwide
Refrigeration; April 2011; "Archived copy" (PDF). Archived (PDF) from
the original on 2012-04-17. Retrieved 2013-02-20.
^ Enright, Ryan (23 Jul 2014). "Dropwise
Condensation on Micro- and
Nanostructured Surfaces". Nanoscale and Microscale Thermophysical
Engineering. 18 (3). doi:10.1080/15567265.2013.862889.
^ a b "Condensation". Property Hive. Archived from the original on
Condensation around the house - what causes condensation".
diydata.com. Archived from the original on 2008-01-13.
States of matter (list)
Gas / Vapor
Quantum spin liquid
Enthalpy of fusion
Enthalpy of sublimation
Enthalpy of vaporization
Latent internal energy
Equation of state
Macroscopic quantum phenomena
Order and disorder (physics)