View source for Ethylene

{| class="toccolours" border="1" style="float: right; clear: right; margin: 0 0 1em 1em; border-collapse: collapse;"
! {{chembox header}} | ''Ethylene''
|-
| align="center" colspan="2" bgcolor="#ffffff" | [[Image:Ethene structural.svg|100px|Ethylene]] [[Image:Ethylene-3D-vdW.png|100px|Ethylene]]
|-
! {{chembox header}} | General
|- 
| [[Chemical formula|Molecular formula]] || C<sub>2</sub>H<sub>4</sub>
|-
| [[Simplified molecular input line entry specification|SMILES]] || C==C
|-
| [[Molar mass]] || 28.05  g/mol
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| Appearance || colorless gas
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! {{chembox header}} | Properties
|-
| [[Density]] and [[Phase (matter)|phase]] || 1.178&nbsp;kg/m³ at 15 °C, gas 
|-
| [[Soluble|Solubility]] in [[Water (molecule)|water]] || 3.5&nbsp;mg/100 ml (17 °C)
|-
<!-- | Other solvents e.g. [[ethanol]], [[acetone]] -->
<!-- | solubility info on other solvents -->
<!-- |- -->
| [[Melting point]] || &minus;169.2 °C (104.0 K, -272.6 °F)
|-
| [[Boiling point]] || &minus;103.7 °C (169.5 K, -154.7 °F)
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! {{chembox header}} | Structure
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| [[Symmetry group]] || D<sub>2h</sub>
|-
| [[Dipole#Molecular dipoles|Dipole moment]]
| Zero
|-
|}

'''Ethylene''' or '''ethene''' is a [[chemical compound]] with two [[carbon]] [[atom]]s and four [[hydrogen]] atoms in each [[molecule]].  These molecules are put together with a [[double bond]] that makes it a [[hydrocarbon]].  It is very important in [[industry]] and has even been used in [[biology]] as a [[hormone]].<ref name=Wang_2002>{{cite journal | author = Wang K, Li H, Ecker J | title = Ethylene biosynthesis and signaling networks. | journal = Plant Cell | year = 2002 | volume = 14 Suppl | issue = Suppl| pages = S131-51 | doi = 10.1105/tpc.001768 | pmid = 12045274 | pmc = 151252 }}</ref>  It is also the most made [[chemical]]. About 75 million tons of it have been made each year since 2005.<ref>“Production: Growth is the Norm” Chemical and Engineering News, July 1 0, 2006, p. 59.</ref> Its biggest use is to make [[polyethylene]].

It is a gas at 25 degrees Celsius at [[standard atmosphere]] (a specific pressure).

==History==
Since [[1795]], ethylene was called an ''olefiant gas'', or ''oil making gas''.  This was because it came together with [[chlorine]] to make the ''oil of the Dutch chemists''.

In [[1866]], the [[Germany|German]] [[chemist]] [[August Wilhelm von Hofmann]] came up with a system for naming hydrocarbons. The [[suffix]]es -ane, -ene, -ine, -one, and -une were used to call the hydrocarbons with 0, 2, 4, 6, and 8 fewer hydrogen atoms than the [[alkane]] it came from.<ref>{{cite web|url=https://www.chem.yale.edu/~chem125/125/history99/5Valence/Nomenclature/Hofmannaeiou.html|title=Hofmann's Proposal for Systematic Nomenclature of the Hydrocarbons|author=A. W. Hofmann, LL.D., F.R.S.|accessdate=2007-01-06|publisher=www.chem.yale.edu|archive-date=2006-09-03|archive-url=https://web.archive.org/web/20060903081507/https://www.chem.yale.edu/~chem125/125/history99/5Valence/Nomenclature/Hofmannaeiou.html|url-status=dead}}</ref>  Because of this system, ethylene became ethene.

In [[1979]], the [[IUPAC]] decided that ethylene would stay ethylene.

==How it is made==
Ethylene is made in the chemical industry by [[steam cracking]].  Some of the parts of an ethylene plant can be:

# The steam cracking furnaces;
# Heat recovery systems;
# A steam recycling system;
# A system to [[compress]] the cracked gas;
# A system to remove [[acid]] gas;

There are other systems in an ethylene plant.  The systems listed above were the most important systems in an ethylene plant.

Since making ethylene uses a lot of energy, the people making the ethylene try very hard to keep the heat from the gasses from leaving the [[furnace]]s.

==References==
{{reflist}}

==Other websites==
*[https://www.ilo.org/public/english/protection/safework/cis/products/icsc/dtasht/_icsc04/icsc0475.htm International Chemical Safety Card 0475]

{{Functional group}}
{{Alkenes}}

[[Category:Alkenes|2]]