Skip to main content
Select Source:

Freon

Freon (frē´ŏn) [trade name], any one of a special class of chemical compounds that are used as refrigerants, aerosol propellants, and solvents. These compounds are haloalkanes, i.e., halogen derivatives of saturated hydrocarbons (see alkane). Every Freon contains at least some fluorine in its molecule, and most contain chlorine or bromine as well. Freons are generally colorless, odorless, nontoxic, noncorrosive, nonflammable, and chemically unreactive. The most commonly used is Freon-12, or dichlorodifluoromethane (CCl2F2), which boils at -29.8°C and is thus a gas at ordinary temperatures and pressures. It is prepared by the reaction of carbon tetrachloride with hydrogen fluoride in the presence of a catalyst. There are a number of other Freons. Some of those containing bromine in their molecules are used in fire extinguishers. See also chlorofluorocarbons.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Freon." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. 17 Aug. 2018 <http://www.encyclopedia.com>.

"Freon." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. (August 17, 2018). http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/freon

"Freon." The Columbia Encyclopedia, 6th ed.. . Retrieved August 17, 2018 from Encyclopedia.com: http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/freon

Learn more about citation styles

Citation styles

Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.

Freon

Fre·on / ˈfrēˌän/ (also fre·on) • n. trademark an aerosol propellant, refrigerant, or organic solvent consisting of one or more of a group of chlorofluorocarbons and related compounds.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Freon." The Oxford Pocket Dictionary of Current English. . Encyclopedia.com. 17 Aug. 2018 <http://www.encyclopedia.com>.

"Freon." The Oxford Pocket Dictionary of Current English. . Encyclopedia.com. (August 17, 2018). http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/freon

"Freon." The Oxford Pocket Dictionary of Current English. . Retrieved August 17, 2018 from Encyclopedia.com: http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/freon

Learn more about citation styles

Citation styles

Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.

Freon

Freon

The generic name for several chlorofluorocarbons (CFCs) widely used in refrigerators and air conditioners, including the systems in houses and cars. Freoncomprised of chlorine , fluorine, and carbon atomsis a non-toxic gas at room temperature. It is environmentally significant because it is extremely long-lived in the atmosphere , with a typical residence time of 70 years. This long life-span permits CFCs to disperse, ultimately reaching the stratosphere 19 mi (30 km) above the earth's surface. Here, high energy photons in sunlight break down freon, and chlorine atoms liberated during this process participate in other chemical reactions that consume ozone . The final result is to decrease the stratospheric ozone layer that shields the earth from damaging ultraviolet radiation . Under the 1987 Montreal Protocol, 31 industrialized countries agreed to phase out CFC freon production. Freon substitutes use bromine atoms to replace the chlorine atoms, providing a substitute refrigeration compound that appears less damaging, although considerably more expensive and less energy efficient.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Freon." Environmental Encyclopedia. . Encyclopedia.com. 17 Aug. 2018 <http://www.encyclopedia.com>.

"Freon." Environmental Encyclopedia. . Encyclopedia.com. (August 17, 2018). http://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/freon

"Freon." Environmental Encyclopedia. . Retrieved August 17, 2018 from Encyclopedia.com: http://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/freon

Learn more about citation styles

Citation styles

Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.