In chemistry, paraffin is the common name for the alkane hydrocarbons with the general formula CnH2n+2. Paraffin wax refers to the solids with n=20–40.

The simplest paraffin molecule is that of methane, CH4, a gas at room temperature. Heavier members of the series, such as that of octane C8H18, appear as liquids at room temperature. The solid forms of paraffin, called paraffin wax, are from the heaviest molecules from C20H42 to C40H82. Paraffin wax was identified by Carl Reichenbach 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 Britain as paraffin oil or just paraffin, which is called kerosene in South Africa, most of the U.S., Australia and New Zealand.

The name is derived from the Latin parum (= barely) + affinis with the meaning here of "lacking affinity", or "lacking reactivity". 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 to 64 °C, and having a density of around 0.9 g/cm3. It is insoluble in water, but soluble in ether, benzene, and certain esters. Paraffin is unaffected by most common chemical reagents, but burns readily.

Pure paraffin wax is an excellent electrical insulator, with an electrical resistivity of between 10^ and 10^ ohm metre. This is better than nearly all other materials except some plastics (notably teflon). It is an effective neutron moderator and was used in James Chadwick's 1932 experiments to identify the neutron. This property is exploited in modified sheetrock for home building material: it is infused in the sheetrock during manufacture so as, when installed, it melts during the day, absorbing heat, and solidifies again at night, releasing the heat. Wax expands considerably when it melts and this allows its use in thermostats for industrial, domestic and, particularly, automobile purposes. Liquid paraffin (medicinal) is used to aid bowel movement in persons suffering chronic constipation; it passes through the alimentary canal without itself being taken into the body, but it limits the amount of water removed from the 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. 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) mounting plates to be tested.

Uses

Gaseous

Fuels

Liquids

Fuels
Medicine (Laxative)
Culinary
Fire breathing
Used in toiletries and cosmetics as a moisturiser or emollient.

Paraffin wax

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
Solid propellant for hybrid rocket motors
Component of surfwax, used for grip on surfboards in surfing
Component of glide wax, used on skis and snowboards.
Friction-reducer, for use on handrails and cement ledges, commonly used in skateboarding
Microwaxhttp://www.microcrystallinewax.net: food additive, a glazing agent with E number E905
Forensics aid: the nitrate test uses paraffin wax to detect nitrates and nitrites on the hand of a shooting suspect
Anti-ozonant agent: blends of paraffin and micro waxes are used in rubber compounds to prevent 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 reduce microphonic feedback caused from the subtle movements of the pole pieces
Wax baths 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

References

Synonyms, Antonyms and Related Words

alcohol, avgas, benzine, briquette, burnable, butane, carbon, charcoal, coal, coal oil, coke, combustible, crude, crude oil, dope, electricity, ethane, ethanol, ethyl, ethyl gas, fireball, firing, flammable, flammable material, fossil oil, fuel, fuel additive, fuel dope, gas, gas carbon, gasoline, heptane, hexane, high-octane gas, high-test, illuminant, illuminating gas, inflammable, inflammable material, isooctane, jet fuel, kerosene, lead-free gas, light source, low-lead gas, luminant, methane, methanol, motor oil, natural gas, octane, oil, peat, pentane, petrol, petroleum, premium gas, propane, propellant, regular, rock oil, rocket fuel, turf

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