Paraffin
Overview
 
In chemistry, paraffin is a term that can be used synonymously with "alkane
Alkane
Alkanes are chemical compounds that consist only of hydrogen and carbon atoms and are bonded exclusively by single bonds without any cycles...

", indicating hydrocarbon
Hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons from which one hydrogen atom has been removed are functional groups, called hydrocarbyls....

s with the general formula CnH2n+2. 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
Methane
Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...

, CH4, a gas at room temperature.
Encyclopedia
In chemistry, paraffin is a term that can be used synonymously with "alkane
Alkane
Alkanes are chemical compounds that consist only of hydrogen and carbon atoms and are bonded exclusively by single bonds without any cycles...

", indicating hydrocarbon
Hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons from which one hydrogen atom has been removed are functional groups, called hydrocarbyls....

s with the general formula CnH2n+2. 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
Methane
Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...

, CH4, a gas at room temperature. Heavier members of the series, such as octane
Octane
Octane is a hydrocarbon and an alkane with the chemical formula C8H18, and the condensed structural formula CH36CH3. Octane has many structural isomers that differ by the amount and location of branching in the carbon chain...

, C8H18, and mineral oil
Mineral oil
A mineral oil is any of various colorless, odorless, light mixtures of alkanes in the C15 to C40 range from a non-vegetable source, particularly a distillate of petroleum....

 appear as liquids at room temperature. The solid forms of paraffin, called paraffin wax
Wax
thumb|right|[[Cetyl palmitate]], a typical wax ester.Wax refers to a class of chemical compounds that are plastic near ambient temperatures. Characteristically, they melt above 45 °C to give a low viscosity liquid. Waxes are insoluble in water but soluble in organic, nonpolar solvents...

, are from the heaviest molecules from C20H42 to C40H82. Paraffin wax was identified by Carl Reichenbach
Carl Reichenbach
Baron Dr. Carl Ludwig von Reichenbach was a notable chemist, geologist, metallurgist, naturalist, industrialist and philosopher, and a member of the prestigious Prussian Academy of Sciences...

 in 1830.

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 isoalkanes are also called isoparaffins. It is distinct from the fuel known in the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

, Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

 and South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

 as paraffin oil or just paraffin, which is called kerosene
Kerosene
Kerosene, sometimes spelled kerosine in scientific and industrial usage, also known as paraffin or paraffin oil in the United Kingdom, Hong Kong, Ireland and South Africa, is a combustible hydrocarbon liquid. The name is derived from Greek keros...

 in most of the U.S., Canada, Australia and New Zealand.

The name is derived from Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 parum ("barely") + affinis, meaning "lacking affinity
Electron affinity
The Electron affinity of an atom or molecule is defined as the amount of energy released when an electron is added to a neutral atom or molecule to form a negative ion....

" or "lacking reactivity" indicating paraffin's unreactive nature )

Paraffin wax

Paraffin wax
Wax
thumb|right|[[Cetyl palmitate]], a typical wax ester.Wax refers to a class of chemical compounds that are plastic near ambient temperatures. Characteristically, they melt above 45 °C to give a low viscosity liquid. Waxes are insoluble in water but soluble in organic, nonpolar solvents...

 (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 46 and 68 °C (114.8 and 154.4 °F), and having a density of around 0.9 g/cm3. It is insoluble in water, but soluble in ether
Diethyl ether
Diethyl ether, also known as ethyl ether, simply ether, or ethoxyethane, is an organic compound in the ether class with the formula . It is a colorless, highly volatile flammable liquid with a characteristic odor...

, benzene
Benzene
Benzene is an organic chemical compound. It is composed of 6 carbon atoms in a ring, with 1 hydrogen atom attached to each carbon atom, with the molecular formula C6H6....

, and certain ester
Ester
Esters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH group is replaced by an -O-alkyl group, and most commonly from carboxylic acids and...

s. Paraffin is unaffected by most common chemical reagent
Reagent
A reagent is a "substance or compound that is added to a system in order to bring about a chemical reaction, or added to see if a reaction occurs." Although the terms reactant and reagent are often used interchangeably, a reactant is less specifically a "substance that is consumed in the course of...

s, but burns
Combustion
Combustion or burning is the sequence of exothermic chemical reactions between a fuel and an oxidant accompanied by the production of heat and conversion of chemical species. The release of heat can result in the production of light in the form of either glowing or a flame...

 readily.

Pure paraffin wax is an excellent electrical insulator
Electrical insulation
thumb|250px|[[Coaxial Cable]] with dielectric insulator supporting a central coreThis article refers to electrical insulation. For insulation of heat, see Thermal insulation...

, with an electrical resistivity
Resistivity
Electrical resistivity is a measure of how strongly a material opposes the flow of electric current. A low resistivity indicates a material that readily allows the movement of electric charge. The SI unit of electrical resistivity is the ohm metre...

 of between 1013 and 1017 ohm metre
Resistivity
Electrical resistivity is a measure of how strongly a material opposes the flow of electric current. A low resistivity indicates a material that readily allows the movement of electric charge. The SI unit of electrical resistivity is the ohm metre...

. This is better than nearly all other materials except some plastics (notably teflon
Polytetrafluoroethylene
Polytetrafluoroethylene is a synthetic fluoropolymer of tetrafluoroethylene that finds numerous applications. PTFE is most well known by the DuPont brand name Teflon....

). It is an effective neutron moderator
Neutron moderator
In nuclear engineering, a neutron moderator is a medium that reduces the speed of fast neutrons, thereby turning them into thermal neutrons capable of sustaining a nuclear chain reaction involving uranium-235....

 and was used in James Chadwick
James Chadwick
Sir James Chadwick CH FRS was an English Nobel laureate in physics awarded for his discovery of the neutron....

's 1932 experiments to identify the neutron.

Paraffin wax (C25H52) is an excellent material to store heat
Phase Change Material
A phase-change material is a substance with a high heat of fusion which, melting and solidifying at a certain temperature, is capable of storing and releasing large amounts of energy...

, having a specific heat capacity of 2.14–2.9 J g−1 K−1 (joule
Joule
The joule ; symbol J) is a derived unit of energy or work in the International System of Units. It is equal to the energy expended in applying a force of one newton through a distance of one metre , or in passing an electric current of one ampere through a resistance of one ohm for one second...

 per gram
Gram
The gram is a metric system unit of mass....

 kelvin
Kelvin
The kelvin is a unit of measurement for temperature. It is one of the seven base units in the International System of Units and is assigned the unit symbol K. The Kelvin scale is an absolute, thermodynamic temperature scale using as its null point absolute zero, the temperature at which all...

) and a heat of fusion
Enthalpy of fusion
The enthalpy of fusion is the change in enthalpy resulting from heating one mole of a substance to change its state from a solid to a liquid. The temperature at which this occurs is the melting point....

 of 200–220 J g−1. This property is exploited in modified drywall
Drywall
Drywall, also known as plasterboard, wallboard or gypsum board is a panel made of gypsum plaster pressed between two thick sheets of paper...

 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. Paraffin wax phase change cooling coupled with retractable radiators was used to cool the electronics of the Lunar Rover
Lunar rover
The Lunar Roving Vehicle or lunar rover was a battery-powered four-wheeled rover used on the Moon in the last three missions of the American Apollo program during 1971 and 1972...

. Wax expands considerably when it melts and this allows its use in thermostat
Thermostat
A thermostat is the component of a control system which regulates the temperature of a system so that the system's temperature is maintained near a desired setpoint temperature. The thermostat does this by switching heating or cooling devices on or off, or regulating the flow of a heat transfer...

s for industrial, domestic and, particularly, automobile purposes.

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 EVA copolymers
Ethylene-vinyl acetate
Ethylene vinyl acetate is the copolymer of ethylene and vinyl acetate. The weight percent vinyl acetate usually varies from 10 to 40%, with the remainder being ethylene....

, microcrystalline wax
Microcrystalline wax
Microcrystalline waxes are a type of wax produced by de-oiling petrolatum, as part of the petroleum refining process. In contrast to the more familiar paraffin wax which contains mostly unbranched alkanes, microcrystalline wax contains a higher percentage of isoparaffinic hydrocarbons and...

, or forms of polyethylene
Polyethylene
Polyethylene or polythene is the most widely used plastic, with an annual production of approximately 80 million metric tons...

. 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 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
Beeswax
Beeswax is a natural wax produced in the bee hive of honey bees of the genus Apis. It is mainly esters of fatty acids and various long chain alcohols...

, may be preferred for such sculpture, but "investment casting
Investment casting
Investment casting is an industrial process based on and also called lost-wax casting, one of the oldest known metal-forming techniques. From 5,000 years ago, when beeswax formed the pattern, to today’s high-technology waxes, refractory materials and specialist alloys, the castings allow the...

 waxes," often paraffin-based, are expressly formulated for the purpose.

Some basketball players are known to use paraffin wax on their hands before big games, so that their hands can be soft for the "catch and shoot".

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/cm3. Liquid paraffin (medicinal)
Liquid paraffin (medicinal)
Medicinal liquid paraffin is a very highly refined mineral white oil used in cosmetics and for medical purposes. This is a UK definition and the term may have different uses in other countries...

 is used to aid bowel movement in persons suffering chronic constipation; it passes through the gastrointestinal tract
Gastrointestinal tract
The human gastrointestinal tract refers to the stomach and intestine, and sometimes to all the structures from the mouth to the anus. ....

 without itself being taken into the body, but it limits the amount of water removed from the stool
Human feces
Human feces , also known as a stool, is the waste product of the human digestive system including bacteria. It varies significantly in appearance, according to the state of the digestive system, diet and general health....

. 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.

It is often used in infrared spectroscopy
Infrared spectroscopy
Infrared spectroscopy is the spectroscopy that deals with the infrared region of the electromagnetic spectrum, that is light with a longer wavelength and lower frequency than visible light. It covers a range of techniques, mostly based on absorption spectroscopy. As with all spectroscopic...

, 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) mounting plates to be tested.

Mineral oil has also seen widespread use in biotechnology for preventing the evaporation of small volumes of liquid during heating. Polymerase chain reaction
Polymerase chain reaction
The polymerase chain reaction is a scientific technique in molecular biology to amplify a single or a few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence....

 samples may need to be overlaid with a layer of mineral oil to prevent evaporation during the high heat (95 °C) required to denature DNA.

Liquids

  • Fuels
  • Paints, Pigments, Dyes and Inks
  • In leather industry for "pull up finish"
  • Medicine (Laxative
    Laxative
    Laxatives are foods, compounds, or drugs taken to induce bowel movements or to loosen the stool, most often taken to treat constipation. Certain stimulant, lubricant, and saline laxatives are used to evacuate the colon for rectal and/or bowel examinations, and may be supplemented by enemas under...

    )
  • Biomedical science (evaporation control during PCR
    Polymerase chain reaction
    The polymerase chain reaction is a scientific technique in molecular biology to amplify a single or a few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence....

    )
  • Culinary
  • Fire breathing
    Fire breathing
    Fire breathing is the act of creating a fireball by breathing a fine mist of fuel over an open flame. Proper technique and the correct fuel create the illusion of danger to enhance the novelty of fire breathing, while reducing the risk to health and safety...

     and fire juggling
  • Used in toiletries and cosmetics
    Cosmetics
    Cosmetics are substances used to enhance the appearance or odor of the human body. Cosmetics include skin-care creams, lotions, powders, perfumes, lipsticks, fingernail and toe nail polish, eye and facial makeup, towelettes, permanent waves, colored contact lenses, hair colors, hair sprays and...

     as a moisturiser or emollient.
  • Used in some pesticides

Paraffin wax

  • Candle-making
    Candle
    A candle is a solid block or cylinder of wax with an embedded wick, which is lit to provide light, and sometimes heat.Today, most candles are made from paraffin. Candles can also be made from beeswax, soy, other plant waxes, and tallow...

  • Coatings for waxed paper or cloth
  • Food-grade paraffin wax:
    • Shiny coating used in candy
      Candy
      Candy, specifically sugar candy, is a confection made from a concentrated solution of sugar in water, to which flavorings and colorants are added...

      -making; although edible, it is nondigestible, passing right through the body without being broken down
    • Coating for many kinds of hard cheese
      Cheese
      Cheese is a generic term for a diverse group of milk-based food products. Cheese is produced throughout the world in wide-ranging flavors, textures, and forms....

      , like Edam cheese
    • Sealant for jars, cans, and bottles
    • Chewing gum additive
  • Investment casting
    Investment casting
    Investment casting is an industrial process based on and also called lost-wax casting, one of the oldest known metal-forming techniques. From 5,000 years ago, when beeswax formed the pattern, to today’s high-technology waxes, refractory materials and specialist alloys, the castings allow the...

  • Anti-caking agent, moisture repellent, and dustbinding coatings for fertilizers
  • Agent for preparation of specimens for histology
    Histology
    Histology is the study of the microscopic anatomy of cells and tissues of plants and animals. It is performed by examining cells and tissues commonly by sectioning and staining; followed by examination under a light microscope or electron microscope...

  • Bullet lubricant – with other ingredients, such as olive oil and beeswax
  • Crayon
    Crayon
    A crayon is a stick of colored wax, charcoal, chalk, or other materials used for writing, coloring, drawing, and other methods of illustration. A crayon made of oiled chalk is called an oil pastel; when made of pigment with a dry binder, it is simply a pastel; both are popular media for color...

    s
  • Solid propellant for hybrid rocket
    Hybrid rocket
    A hybrid rocket is a rocket with a rocket motor which uses propellants in two different states of matter - one solid and the other either gas or liquid. The Hybrid rocket concept can be traced back at least 75 years....

     motors
  • Component of surfwax, used for grip on surfboards in surfing
    Surfing
    Surfing' is a surface water sport in which the surfer rides a surfboard on the crest and face of a wave which is carrying the surfer towards the shore...

  • Component of glide wax
    Ski wax
    Ski wax is a material applied to the bottom of skis or snowboards to improve the ski's performance on snow. It can also be applied to other devices that slide over snow and ice such as toboggans.- Types of ski wax :...

    , used on ski
    Ski
    A ski is a long, flat device worn on the foot, usually attached through a boot, designed to help the wearer slide smoothly over snow. Originally intended as an aid to travel in snowy regions, they are now mainly used for recreational and sporting purposes...

    s and snowboard
    Snowboard
    Snowboards are boards, usually with a width the length of one's foot, with the ability to glide on snow. Snowboards are differentiated from monoskis by the stance of the user...

    s
  • Friction-reducer, for use on handrails and cement ledges, commonly used in skateboarding
    Skateboarding
    Skateboarding is an action sport which involves riding and performing tricks using a skateboard.Skateboarding can be a recreational activity, an art form, a job, or a method of transportation. Skateboarding has been shaped and influenced by many skateboarders throughout the years. A 2002 report...

  • 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: food additive
    Food additive
    Food additives are substances added to food to preserve flavor or enhance its taste and appearance.Some additives have been used for centuries; for example, preserving food by pickling , salting, as with bacon, preserving sweets or using sulfur dioxide as in some wines...

    , a glazing agent
    Glazing agent
    Glazing agents, or polishing agents, are food additives providing shiny appearance or protective coating to foods. Mostly they are based on waxes.Examples are:* Stearic acid * Beeswax * Candelilla wax...

     with E number
    E number
    E numbers are number codes for food additives that have been assessed for use within the European Union . They are commonly found on food labels throughout the European Union. Safety assessment and approval are the responsibility of the European Food Safety Authority...

     E905
  • Forensics aid: the nitrate test uses paraffin wax to detect nitrates and nitrites on the hand of a shooting suspect
  • Antiozonant
    Antiozonant
    An antiozonant, also known as anti-ozonant, is a chemical compound that prevents or slows down the degradation of material caused by ozone gas in the air...

     agents: blends of paraffin and micro waxes are used in rubber compounds to prevent cracking
    Ozone cracking
    Cracks can be formed in many different elastomers by ozone attack, and the characteristic form of attack of vulnerable rubbers is known as ozone 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
  • "Potting" guitar pickups, which reduces microphonic feedback caused from the subtle movements of the pole pieces
  • "Potting" of local oscillator coils to prevent microphonic frequency modulation in low end FM radios.
  • Wax baths for beauty
    Beauty
    Beauty is a characteristic of a person, animal, place, object, or idea that provides a perceptual experience of pleasure, meaning, or satisfaction. Beauty is studied as part of aesthetics, sociology, social psychology, and culture...

     and therapy purposes
  • Thickening agent in many Paintballs, as used by Crayola
    Crayola
    Crayola is a brand of artists' supplies manufactured by Crayola LLC, which was founded in 1885 as Binney & Smith. It is best known for its crayons...

  • An effective, although comedogenic, moisturiser in toiletries and cosmetics
    Cosmetics
    Cosmetics are substances used to enhance the appearance or odor of the human body. Cosmetics include skin-care creams, lotions, powders, perfumes, lipsticks, fingernail and toe nail polish, eye and facial makeup, towelettes, permanent waves, colored contact lenses, hair colors, hair sprays and...

     such as Vaseline
    Vaseline
    Vaseline is a brand of petroleum jelly based products owned by Anglo-Dutch company Unilever. Products include plain petroleum jelly and a selection of skin creams, soaps, lotions, cleansers, deodorants and personal lubricants....

  • Prevents oxidation on the surface of polished steel and iron
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