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{{two other uses||the fuel called "paraffin" in [[the UK]] and [[South Africa]]|Kerosene}}
In chemistry, '''paraffin''' is a term that can be used synonymously with "[[alkane]]", indicating [[hydrocarbon]]s with the general formula C<sub>''n''</sub>H<sub>2''n''+2</sub>. '''Paraffin wax''' refers to a mixture of alkanes that falls within the 20 ≤ ''n'' ≤ 40 range; they are found in the solid state at room temperature and begin to enter the liquid phase past approximately 37°C.

The simplest paraffin molecule is that of [[methane]], CH<SUB>4</SUB>, a gas at room temperature. Heavier members of the series, such as [[octane]], C<SUB>8</SUB>H<SUB>18</SUB>, and [[mineral oil]] appear as liquids at room temperature. The solid forms of paraffin, called ''paraffin [[wax]]'', are from the heaviest molecules from C<sub>20</sub>H<sub>42</sub> to C<sub>40</sub>H<sub>82</sub>. Paraffin wax was identified by [[Carl Reichenbach]] in 1830.<ref>''[[Encyclopædia Britannica Eleventh Edition|Britannica]]'' (1911)</ref>

Paraffin, or ''paraffin hydrocarbon'', is also the technical name for an alkane in general, but in most cases it refers specifically to a linear, or ''normal'' alkane — whereas branched, or ''iso''alkanes are also called ''iso''paraffins. It is distinct from the fuel known in Ireland, Britain and [[South Africa]] as ''paraffin oil'' or just ''paraffin'', which is called [[kerosene]] in most of the U.S., Canada, Australia and New Zealand.

The name is derived from the Latin ''parum'' (= barely) + ''affinis'' with the meaning here of "lacking [[electron affinity|affinity]]", or "lacking [[reactivity]]".<ref>{{cite book|title=[[Oxford English Dictionary]]|publisher=Oxford University Press|location=Oxford, England|date=March 2009|chapter=Paraffin, n}}</ref> This is because alkanes, being [[non-polar]] and lacking in [[functional groups]], are very unreactive.

==Wax==
Paraffin [[wax]] (or simply "paraffin", but see alternative name for ''kerosene'', above) is mostly found as a white, odorless, tasteless, waxy solid, with a typical melting point between about 47 °C and 64 °C ( 117°F to 147°F), and having a density of around 0.9 g/cm<sup>3</sup>.<ref name=kayelabymech>{{cite web
  | last =Kaye
  | first =George William Clarkson
  | authorlink =
  | coauthors =[[T. H. Laby|Laby,Thomas Howell]]
  | title =Mechanical properties of materials
  | work =Kaye and Laby Tables of Physical and Chemical Constants
  | publisher =[[National Physical Laboratory, UK|National Physical Laboratory]]
  | date =
  | url =http://www.kayelaby.npl.co.uk/general_physics/2_2/2_2_1.html
  | doi =
  | accessdate = 2008-03-06 }}</ref> It is insoluble in water, but soluble in [[diethyl ether|ether]], [[benzene]], and certain [[ester]]s. Paraffin is unaffected by most common chemical [[reagent]]s, but [[combustion|burns]] readily.

Pure paraffin wax is an excellent electrical [[Electrical insulation|insulator]], with an electrical [[resistivity]] of between 10<sup>13</sup> and 10<sup>17</sup> [[Resistivity|ohm metre]].<ref name =kayelabyelec>{{cite web
  | last =
  | first =
  | authorlink =
  | coauthors =
  | title =Electrical insulating materials
  | work =Kaye and Laby Tables of Physical and Chemical Constants
  | publisher =National Physical Laboratory
  | date =1995
  | url =http://www.kayelaby.npl.co.uk/general_physics/2_6/2_6_3.html
  | doi =
  | accessdate = 2007-04-23 }}</ref> This is better than nearly all other materials except some plastics (notably [[polytetrafluoroethylene|teflon]]). It is an effective [[neutron moderator]] and was used in [[James Chadwick]]'s 1932 [[Wikibooks:A-level Physics/Forces, Fields and Energy/The nuclear atom|experiments to identify the neutron]].<ref>{{cite web
  | last =
  | first =
  | authorlink =
  | coauthors =
  | title =Attenuation of fast neutrons: neutron moderation and diffusion
  | work =Kaye and Laby Tables of Physical and Chemical Constants
  | publisher =National Physical Laboratory
  | date =
  | url =http://www.kayelaby.npl.co.uk/atomic_and_nuclear_physics/4_7/4_7_3.html
  | doi =
  | accessdate = 2007-04-23 }}</ref><ref>{{cite book
  | last =Rhodes
  | first =Richard
  | authorlink =Richard Rhodes
  | coauthors =
  | title =The Making of the Atomic Bomb
  | publisher =Simon and Schuster
  | date =1986
  | location =New York
  | pages = 163
  | url =
  | doi =
  | isbn =  0-671-44133-7}}</ref>

Paraffin wax (C<sub>25</sub>H<sub>52</sub>) is an excellent material to [[Phase change material|store heat]], having a [[specific heat capacity]] of 2.14–2.9&nbsp;J&nbsp;g<sup>−1</sup>&nbsp;K<sup>−1</sup> ([[joule]] per [[gram]] per [[kelvin]]) and a [[Enthalpy of fusion|heat of fusion]] of 200–220&nbsp;J&nbsp;g<sup>−1</sup>.<ref>{{cite web
  | last =
  | first =
  | authorlink =
  | coauthors =
  | title =Specific Heat Capacity
  | work =Diracdelta.co.uk Science and Engineering Encyclopedia
  | publisher =Dirac Delta Consultants Ltd, Warwick, England
  | date =
  | url =http://www.diracdelta.co.uk/science/source/s/p/specific%20heat%20capacity/source.html
  | doi =
  | accessdate = 2007-08-18 }}</ref> This property is exploited in modified [[drywall]] for home building material: it is infused in the drywall during manufacture so that, when installed, it melts during the day, absorbing heat, and solidifies again at night, releasing the heat.<ref>{{cite web | title = Micronal PCM SmartBoard | url = http://www.micronal.de/portal/basf/ien/dt.jsp?setCursor=1_290798 }}</ref> Paraffin wax phase change cooling coupled with retractable radiators was used to cool the electronics of the [[Lunar Rover]].<ref>{{cite web|url=http://adsabs.harvard.edu/abs/1993lock.rept.....D|title=Space Station thermal storage/refrigeration system research and development|last=Dean|first=W. G.|coauthors=Karu, Z. S.|date=February 1993|work=Lockheed Missiles and Space Co. Report|publisher=[[NASA]]|accessdate=28 November 2008}}</ref> Wax expands considerably when it melts and this allows its use in [[thermostat]]s for industrial, domestic and, particularly, automobile purposes.<ref>[http://www.freepatentsonline.com/4948043.html Wax-pellet thermostat] United States Patent 4948043</ref><ref name=rogerboden>

{{cite web
| last =Bodén
| first =Roger
| authorlink =
| coauthors =
| title =Paraffin Microactuator
| work =Materials Science Sensors and Actuators
| publisher =University of Uppsala
| date =
| url =http://hermes.material.uu.se/~klas/Paraffin_lab_eng.pdf
| format =
| doi =
| accessdate =2007-04-23 }}</ref>

In industrial applications, it is often useful to modify the crystal properties of the paraffin wax, typically by adding branching to the existing carbon backbone chain.  The modification is usually done with additives, such as [[Ethylene-vinyl acetate|EVA copolymers]], [[microcrystalline wax]], or forms of [[polyethylene]].  The branched properties result in a modified paraffin with a higher viscosity, smaller crystalline structure, and modified functional properties. Pure paraffin wax is rarely used for carving original models for [[Casting (metalworking)|casting]] metal and other materials in the [[lost wax process]], as it is relatively brittle at room temperature and presents the risks of chipping and breakage when worked. Soft and pliable waxes, like [[beeswax]], may be preferred for such sculpture, but "[[investment casting]] waxes," often paraffin-based, are expressly formulated for the purpose.

==Mineral oil==
{{Main|Mineral oil}}
Liquid paraffin, or mineral oil, is a mixture of heavier alkanes, and has a number of names, including nujol, adepsine oil, [[alboline]], glymol, medicinal paraffin, or saxol. It has a density of around 0.8 g/cm<sup>3</sup>.<ref name=kayelabymech>{{cite web
  | last =
  | first =
  | authorlink =
  | coauthors =
  | title =Mechanical properties of materials
  | work =Kaye and Laby Tables of Physical and Chemical Constants
  | publisher =National Physical Laboratory
  | date =
  | url =http://www.kayelaby.npl.co.uk/general_physics/2_2/2_2_1.html
  | doi =
  | accessdate = 2008-03-06 }}</ref> [[Liquid paraffin (medicinal)]] is used to aid bowel movement in persons suffering chronic constipation; it passes through the [[gastrointestinal tract]] without itself being taken into the body, but it limits the amount of water removed from the [[Human feces|stool]]. In the food industry, where it may be called "wax", it can be used as a lubricant in mechanical mixing, applied to baking tins to ensure that loaves are easily released when cooked and as a coating for fruit or other items requiring a "shiny" appearance for sale.<ref>{{cite web
 | last =
  | first =
  | authorlink =
  | coauthors =
  | title =Mineral Oil (Food Grade)
  | work =WHO Food Additives Series 10
  | publisher =Food and Agriculture Organization of the United Nations; World Health Organization 
  | date =1976
  | url =http://www.inchem.org/documents/jecfa/jecmono/v10je08.htm
  | doi =
  | accessdate =  2007-08-21}}</ref>  It is often used in [[infrared spectroscopy]], as it has a relatively uncomplicated [[IR spectrum]]. When the sample to be tested is made into a mull (a very thick paste), liquid paraffin is added so it can be spread on the transparent (to infrared) [[Infrared spectroscopy#Sample preparation|mounting plates]] to be tested.

==Uses==
===Gaseous===
*Fuels
===Liquids===
*Fuels
*Paints, Pigments, Dyes and Inks
*In leather industry for "pull up finish"<ref>{{cite web|url=http://www.je-sedgwick.co.uk/jes/mib/d/dyed+saddle+leather+german+pull+up+finish/pid/7723339/|title=Dyed saddle leather—German pull up finish|publisher=J & E Sedgwick |accessdate=14 April 2010|location=Walsall, England|quote=applying specially formulated mineral oils to the open grain of the leather}}</ref>
*Medicine ([[Laxative]])
*Biomedical science (evaporation control during [[Polymerase Chain Reaction|PCR]])
*Culinary
*[[Fire breathing]] and [[Poi (juggling)#Fire poi|fire juggling]]
*Used in [[toiletries]] and [[cosmetics]] as a [[moisturiser]] or [[emollient]].

=== Paraffin wax ===
* [[Candle|Candle-making]]
* Coatings for waxed paper or cloth
* Food-grade paraffin wax:
** Shiny coating used in [[candy]]-making; although edible, it is nondigestible, passing right through the body without being broken down
** Coating for many kinds of hard [[cheese]], like [[Edam cheese]]
** Sealant for jars, cans, and bottles
** Chewing gum additive
* [[Investment casting]]
* Anti-caking agent, moisture repellent, and dustbinding coatings for [[fertilizers]]
* Agent for preparation of specimens for [[histology]]
* Bullet lubricant – with other ingredients, such as olive oil and beeswax
* [[crayon|Crayons]]
* Solid propellant for [[hybrid rocket]] motors<ref>{{cite journal|last=Staff|date=Fall 2004|title=Rocket motor uses common household product for fuel|journal=OASIS Ocean Air Space Industry Site|publisher=[[NASA]]|location=Stennis Space Center Pearlington, MS|volume=1|issue=3|pages=6|url=http://www.nasa.gov/centers/stennis/pdf/69281main_fall.pdf|accessdate=28 November 2008}}</ref>
* Component of [[surfwax]], used for grip on surfboards in [[surfing]]
* Component of [[ski wax|glide wax]], used on [[ski]]s and [[snowboard]]s
* Friction-reducer, for use on handrails and cement ledges, commonly used in [[skateboarding]]
* Ink. Used as the basis for solid ink different color blocks of wax for thermal printers. The wax is melted and then sprayed on the paper producing images with a shiny surface
* Microwax<ref>[http://www.microcrystallinewax.net]</ref>: [[food additive]], a [[glazing agent]] with [[E number]] E905
* Forensics aid: the [[Paraffin wax nitrate test|nitrate test]] uses paraffin wax to detect nitrates and nitrites on the hand of a shooting suspect
* [[Antiozonant]] agents: blends of paraffin and micro waxes are used in rubber compounds to prevent [[Ozone cracking|cracking]] of the rubber; the antiozonant waxes can be produced from synthetic waxes, FT wax, and Fischer Tropsch wax
* Mechanical thermostats and actuators, as an expansion medium for activating such devices<ref name=rogerboden/>
* "Potting" [[Pick up (music technology)|guitar pickups]], which reduces microphonic feedback caused from the subtle movements of the pole pieces
* [[Wax bath]]s for [[beauty]] and therapy purposes
* Thickening agent in many [[Paintballs]], as used by [[Crayola]]
* An effective, although [[comedogenic]], [[moisturiser]] in [[toiletries]] and [[cosmetics]] such as [[Vaseline]]
* Prevents oxidation on the surface of polished steel and iron<ref>

{{cite web
| last =Dick
| first =William B
| authorlink =
| coauthors =
| title =Encyclopedia Of Practical Receipts And Processes
| work =
| publisher =
| date =
| url =http://chestofbooks.com/reference/Encyclopedia-Of-Practical-Receipts-And-Processes/Steel-Part-6.html
| doi =
| accessdate =2008-04-27 }}</ref>

==References==
<REFERENCES/>
==See also==
* [[Oligomer]]

[[Category:Waxes]]
[[Category:Alkanes]]
[[Category:Petroleum products]]
[[Category:Food additives]]

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