condensation

condensation
—condensational, adj. —condensative, adj.
/kon'den say"sheuhn, -deuhn-/, n.
1. the act of condensing; the state of being condensed.
2. the result of being made more compact or dense.
3. reduction of a book, speech, statement, or the like, to a shorter or terser form; abridgment.
4. a condensed form: Did you read the whole book or just a condensation?
5. a condensed mass.
6. (in nontechnical usage) condensate.
7. the act or process of reducing a gas or vapor to a liquid or solid form.
8. Chem. a reaction between two or more organic molecules leading to the formation of a larger molecule and the elimination of a simple molecule such as water or alcohol.
9. Meteorol. the process by which atmospheric water vapor liquefies to form fog, clouds, or the like, or solidifies to form snow or hail.
10. Psychoanal. the representation of two or more ideas, memories, feelings, or impulses by one word or image, as in a person's humor, accidental slips, or dreams.
11. Physics. the relative amount by which the density of an elastic medium varies from its average value as a sound wave passes through it.
[1595-1605; < LL condensation- (s. of condensatio), equiv. to condensat(us) CONDENSATE + -ion- -ION]

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Formation of a liquid or solid from its vapour.

Condensation usually occurs on a surface that is cooler than the adjacent gas. A substance condenses when the pressure exerted by its vapour exceeds the vapour pressure of its liquid or solid phase at the temperature of the surface where the condensation is to occur. The process causes the release of thermal energy. Condensation occurs on a glass of cold water on a warm, humid day when water vapour in the air condenses to form liquid water on the glass's colder surface. Condensation also accounts for the formation of dew, fog, rain, snow, and clouds.

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▪ phase change
      deposition of a liquid or a solid from its vapour, generally upon a surface that is cooler than the adjacent gas. A substance condenses when the pressure exerted by its vapour exceeds the vapour pressure of the liquid or solid phase of the substance at the temperature of the surface where condensation (condensation nucleus) occurs. Heat is released when a vapour condenses. Unless this heat is removed, the surface temperature will increase until it is equal to that of the surrounding vapour.

      If air were free of tiny particles, called aerosols, condensation would only occur when the air was extremely supersaturated with water vapour. In the atmosphere, however, there is an abundant supply of aerosols, which serve as nuclei, called condensation nuclei, on which water vapour may condense. Some are hygroscopic (moisture-attracting), and condensation begins on them when the relative humidity is less than 100 percent, but other nuclei require some supersaturation before condensation begins.

      In the atmosphere the relative humidity of the air is increased, and condensation results when air temperature is reduced to the dew point or when sufficient water vapour is added to saturate the air. Condensation accounts for the formation of dew, fog, and clouds. For rain to occur, other physical processes are required.

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Universalium. 2010.

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  • condensation — [ kɔ̃dɑ̃sasjɔ̃ ] n. f. • 1361; lat. imp. condensatio 1 ♦ Passage d un corps de la phase gazeuse à une des phases condensées, liquide ou solide; action de condenser. Point de condensation (cf. Point de rosée). ⇒ saturation. Condensation de la… …   Encyclopédie Universelle

  • Condensation — Con den*sa tion, n. [L. condensatio: cf. F. condensation.] 1. The act or process of condensing or of being condensed; the state of being condensed. [1913 Webster] He [Goldsmith] was a great and perhaps an unequaled master of the arts of selection …   The Collaborative International Dictionary of English

  • condensation — CONDENSATION. s. f. Terme de Physique, qui se dit par opposition à Raréfaction, et qui signifie L action par laquelle un corps est ren du plus dense, plus compacte, plus serré. La condensation de l air …   Dictionnaire de l'Académie Française 1798

  • condensation — [n1] abridgment abstract, boildown*, breviary, brief, compendium, compression, concentration, consolidation, conspectus, contraction, curtailment, digest, epitome, essence, précis, reduction, summary, synopsis; concepts 283,730 Ant. unabridgment… …   New thesaurus

  • condensation — Condensation. s. f. v. Action par laquelle un corps est condensé. Il se dit aussi de l effet de la condensation …   Dictionnaire de l'Académie française

  • condensation — [kän΄dən sā′shən] n. [LL condensatio] 1. the act of condensing, as the reduction of a gas to a liquid or the abridgment of a piece of writing 2. the product of such an act [to read a condensation of a novel] 3. the condition of being condensed …   English World dictionary

  • condensation — index abstract, adhesion (affixing), brief, capsule, centralization, compendium, congealment, curtailment …   Law dictionary

  • condensation — c.1600, action of becoming more dense, from L. condensationem (nom. condensatio), noun of action from condensare (see CONDENSE (Cf. condense)). Meaning conversion of a gas to a liquid is from 1610s …   Etymology dictionary

  • condensation — ► NOUN 1) water from humid air collecting as droplets on a cold surface. 2) the conversion of a vapour or gas to a liquid. 3) a concise version of something …   English terms dictionary

  • Condensation — For other uses, see Condensation (disambiguation). Water vapour condenses into a liquid after making contact with the surface of a cold bottle …   Wikipedia

  • Condensation — Pour les articles homonymes, voir Condensation (homonymie). En thermodynamique, la condensation désigne le passage d un corps pur de l état gazeux directement à l état solide, sans passer par l état liquide[1]. Pour la terminologie des… …   Wikipédia en Français

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