Oil

Oil

Overview
An oil is any substance
Chemical substance
In chemistry, a chemical substance is a form of matter that has constant chemical composition and characteristic properties. It cannot be separated into components by physical separation methods, i.e. without breaking chemical bonds. They can be solids, liquids or gases.Chemical substances are...

 that is liquid
Liquid
Liquid is one of the three classical states of matter . Like a gas, a liquid is able to flow and take the shape of a container. Some liquids resist compression, while others can be compressed. Unlike a gas, a liquid does not disperse to fill every space of a container, and maintains a fairly...

 at ambient temperatures
Room temperature
-Comfort levels:The American Society of Heating, Refrigerating and Air-Conditioning Engineers has listings for suggested temperatures and air flow rates in different types of buildings and different environmental circumstances. For example, a single office in a building has an occupancy ratio per...

 and does not mix with water but may mix with other oils and organic solvents. This general definition includes vegetable oils, volatile essential oils, petrochemical
Petrochemistry
Petrochemistry is a branch of chemistry that studies the transformation of crude oil and natural gas into useful products or raw materials. These petrochemicals have become an essential part of the chemical industry today.-Origin of Petroleum:...

 oils, and synthetic oils.

First attested in English 1176, the word oil comes from Old French
Old French
Old French was the Romance dialect continuum spoken in territories that span roughly the northern half of modern France and parts of modern Belgium and Switzerland from the 9th century to the 14th century...

 "oile", 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...

 "oleum", which in turn comes from the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...

 "ἔλαιον" (elaion), "olive oil, oil" and that from "ἐλαία" (elaia), "olive tree".
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Quotations

"Moses dragged us through the desert for 40 years to bring us to the one place in the Middle East where there was no oil." ~ Golda Meir

"The use of solar energy has not been opened up because the oil industry does not own the sun." ~ Ralph Nader

"Overdrafts on aquifers are one reason some of our geologist colleagues are convinced that water shortages will bring the human population explosion to a halt. There are substitutes for oil; there is no substitute for fresh water." ~ Paul R. Ehrlich

"Nobody thinks the United States went to strike against Iraq in order to gain land or water or oil, nobody thinks America has any ambitions about real estate." ~ Shimon Peres

"So when you go up against the Far Right you go up against the big financial special interests like the Halliburtons of the world, the big oil companies, the big energy companies who work so hard to rip us off." ~ Barbara Boxer

"This war has been motivated by pride or arrogance, by a desire to control oil wealth, by a desire to implant our programs." ~ Jimmy Carter

"No young American should be held hostage to America's dependence on oil" ~ John Kerry

"The House okayed the gasoline tax cut, which will increase the deficit, line the pockets of the oil companies, and hurt the environment; Dole said that if there was just some way this could interfere with people's sex lives, it would be perfect legislation." ~ Bill Maher

"This is going to be a very expensive war, and Victory is not guaranteed— for anyone, and certainly not for anyone as baffled as George W. Bush. All he knows is that his father started the war a long time ago, and that he, the goofy child-President, has been chosen by Fate and the global Oil industry to finish it Now." ~ Hunter S. Thompson

Encyclopedia
An oil is any substance
Chemical substance
In chemistry, a chemical substance is a form of matter that has constant chemical composition and characteristic properties. It cannot be separated into components by physical separation methods, i.e. without breaking chemical bonds. They can be solids, liquids or gases.Chemical substances are...

 that is liquid
Liquid
Liquid is one of the three classical states of matter . Like a gas, a liquid is able to flow and take the shape of a container. Some liquids resist compression, while others can be compressed. Unlike a gas, a liquid does not disperse to fill every space of a container, and maintains a fairly...

 at ambient temperatures
Room temperature
-Comfort levels:The American Society of Heating, Refrigerating and Air-Conditioning Engineers has listings for suggested temperatures and air flow rates in different types of buildings and different environmental circumstances. For example, a single office in a building has an occupancy ratio per...

 and does not mix with water but may mix with other oils and organic solvents. This general definition includes vegetable oils, volatile essential oils, petrochemical
Petrochemistry
Petrochemistry is a branch of chemistry that studies the transformation of crude oil and natural gas into useful products or raw materials. These petrochemicals have become an essential part of the chemical industry today.-Origin of Petroleum:...

 oils, and synthetic oils.

Etymology


First attested in English 1176, the word oil comes from Old French
Old French
Old French was the Romance dialect continuum spoken in territories that span roughly the northern half of modern France and parts of modern Belgium and Switzerland from the 9th century to the 14th century...

 "oile", 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...

 "oleum", which in turn comes from the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...

 "ἔλαιον" (elaion), "olive oil, oil" and that from "ἐλαία" (elaia), "olive tree". The earliest attested form of the word is the Mycenaean Greek e-ra-wo, written in Linear B
Linear B
Linear B is a syllabic script that was used for writing Mycenaean Greek, an early form of Greek. It pre-dated the Greek alphabet by several centuries and seems to have died out with the fall of Mycenaean civilization...

 syllabic script.

Organic oils


Organic oils are produced in remarkable diversity by plants, animals, and other organisms through natural metabolic processes. Lipid
Lipid
Lipids constitute a broad group of naturally occurring molecules that include fats, waxes, sterols, fat-soluble vitamins , monoglycerides, diglycerides, triglycerides, phospholipids, and others...

is the scientific term for the fatty acid
Fatty acid
In chemistry, especially biochemistry, a fatty acid is a carboxylic acid with a long unbranched aliphatic tail , which is either saturated or unsaturated. Most naturally occurring fatty acids have a chain of an even number of carbon atoms, from 4 to 28. Fatty acids are usually derived from...

s, steroid
Steroid
A steroid is a type of organic compound that contains a characteristic arrangement of four cycloalkane rings that are joined to each other. Examples of steroids include the dietary fat cholesterol, the sex hormones estradiol and testosterone, and the anti-inflammatory drug dexamethasone.The core...

s and similar chemicals often found in the oils produced by living things, while oil refers to an overall mixture of chemicals. Organic oils may also contain chemicals other than lipids, including protein
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

s, 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...

es and alkaloid
Alkaloid
Alkaloids are a group of naturally occurring chemical compounds that contain mostly basic nitrogen atoms. This group also includes some related compounds with neutral and even weakly acidic properties. Also some synthetic compounds of similar structure are attributed to alkaloids...

s.

Lipids can be classified by the way that they are made by an organism, their chemical structure and their limited solubility
Solubility
Solubility is the property of a solid, liquid, or gaseous chemical substance called solute to dissolve in a solid, liquid, or gaseous solvent to form a homogeneous solution of the solute in the solvent. The solubility of a substance fundamentally depends on the used solvent as well as on...

 in water compared to oils. They have a high carbon
Carbon
Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...

 and hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

 content and are considerably lacking in oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...

 compared to other organic compounds and minerals; they tend to be relatively nonpolar
Chemical polarity
In chemistry, polarity refers to a separation of electric charge leading to a molecule or its chemical groups having an electric dipole or multipole moment. Polar molecules interact through dipole–dipole intermolecular forces and hydrogen bonds. Molecular polarity is dependent on the difference in...

 molecules, but may include both polar and nonpolar regions as in the case of phospholipid
Phospholipid
Phospholipids are a class of lipids that are a major component of all cell membranes as they can form lipid bilayers. Most phospholipids contain a diglyceride, a phosphate group, and a simple organic molecule such as choline; one exception to this rule is sphingomyelin, which is derived from...

s and steroids.

Mineral oils


Crude oil, or petroleum, and its refined components, collectively termed petrochemicals, are crucial resources in the modern economy. Crude oil originates from ancient fossilized organic materials, such as zooplankton
Zooplankton
Zooplankton are heterotrophic plankton. Plankton are organisms drifting in oceans, seas, and bodies of fresh water. The word "zooplankton" is derived from the Greek zoon , meaning "animal", and , meaning "wanderer" or "drifter"...

 and algae
Algae
Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...

, which geochemical processes convert into oil. It is classified as a mineral oil because it does not have an organic origin on human timescales, but is instead obtained from rocks, underground traps, or sands. 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....

also refers to several specific distillates of crude oil.

Applications




Cosmetics


Oils are applied to hair to give it a lustrous look, to prevent tangles and roughness and to stabilize the hair to promote growth. See Hair conditioner
Hair conditioner
Hair conditioner is a hair care product that alters the texture and appearance of hair.-History:For centuries, natural oils have been used to condition human hair. These natural products are still used today, including essential oils such as tea tree oil and carrier oils such as jojoba oil...

.

Religion


Oils are commonly used in ritual anointments. As a particular example, Holy anointing oil
Holy anointing oil
The holy anointing oil , formed an integral part of the ordination of the priesthood and the high priest as well as in the consecration of the articles of the tabernacle and subsequent temples in Jerusalem...

 has been an important ritual liquid for Judaism
Judaism
Judaism ) is the "religion, philosophy, and way of life" of the Jewish people...

 and Christianity
Christianity
Christianity is a monotheistic religion based on the life and teachings of Jesus as presented in canonical gospels and other New Testament writings...

.

Painting


Color pigments are easily suspended
Suspension (chemistry)
In chemistry, a suspension is a heterogeneous fluid containing solid particles that are sufficiently large for sedimentation. Usually they must be larger than 1 micrometer. The internal phase is dispersed throughout the external phase through mechanical agitation, with the use of certain...

 in oil, making it suitable as a supporting medium for paints
Oil paint
Oil paint is a type of slow-drying paint that consists of particles of pigment suspended in a drying oil, commonly linseed oil. The viscosity of the paint may be modified by the addition of a solvent such as turpentine or white spirit, and varnish may be added to increase the glossiness of the...

. The oldest known extant oil paintings date from 650 AD.

Heat transfer


Oils are used as coolants in oil cooling
Oil cooling
Oil cooling refers to a process whereby heat is displaced from a 'hotter' object, into a cooler oil and is the principle behind oil cooler devices. The oil carrying the displaced heat usually passes through a cooling unit such as a radiator or less commonly a gas decompresser...

, for instance in electric transformers. Oils are also used to enhance heating in other applications, such as cooking (especially in frying
Frying
Frying is the cooking of food in oil or another fat, a technique that originated in ancient Egypt around 2500 BC. Chemically, oils and fats are the same, differing only in melting point, but the distinction is only made when needed. In commerce, many fats are called oils by custom, e.g...

).

Lubrication


Oils are commonly used as lubricant
Lubricant
A lubricant is a substance introduced to reduce friction between moving surfaces. It may also have the function of transporting foreign particles and of distributing heat...

s. Mineral oils are more more commonly used as machine lubricants than biological oils are.

Fuel


Some oils burn
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...

 in liquid or aerosol
Aerosol
Technically, an aerosol is a suspension of fine solid particles or liquid droplets in a gas. Examples are clouds, and air pollution such as smog and smoke. In general conversation, aerosol usually refers to an aerosol spray can or the output of such a can...

 form, generating heat
Heat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...

 which can be used directly or converted into other forms of energy such as electricity or mechanical work. To obtain most of these oils, crude oil is pumped from the ground and is shipped via oil tanker
Oil tanker
An oil tanker, also known as a petroleum tanker, is a merchant ship designed for the bulk transport of oil. There are two basic types of oil tankers: the crude tanker and the product tanker. Crude tankers move large quantities of unrefined crude oil from its point of extraction to refineries...

 to an oil refinery
Oil refinery
An oil refinery or petroleum refinery is an industrial process plant where crude oil is processed and refined into more useful petroleum products, such as gasoline, diesel fuel, asphalt base, heating oil, kerosene, and liquefied petroleum gas...

. There, it is converted from crude oil to diesel fuel (petrodiesel), ethane
Ethane
Ethane is a chemical compound with chemical formula C2H6. It is the only two-carbon alkane that is an aliphatic hydrocarbon. At standard temperature and pressure, ethane is a colorless, odorless gas....

 (and other short-chain alkanes), fuel oil
Fuel oil
Fuel oil is a fraction obtained from petroleum distillation, either as a distillate or a residue. Broadly speaking, fuel oil is any liquid petroleum product that is burned in a furnace or boiler for the generation of heat or used in an engine for the generation of power, except oils having a flash...

s (heaviest of commercial fuels, used in ships/furnaces), gasoline
Gasoline
Gasoline , or petrol , is a toxic, translucent, petroleum-derived liquid that is primarily used as a fuel in internal combustion engines. It consists mostly of organic compounds obtained by the fractional distillation of petroleum, enhanced with a variety of additives. Some gasolines also contain...

 (petrol), jet fuel
Jet fuel
Jet fuel is a type of aviation fuel designed for use in aircraft powered by gas-turbine engines. It is clear to straw-colored in appearance. The most commonly used fuels for commercial aviation are Jet A and Jet A-1 which are produced to a standardized international specification...

, 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...

, 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....

 (historically), and liquefied petroleum gas. A 42 gallon barrel (U.S.) of crude oil produces approximately 10 gallons of diesel, 4 gallons of jet fuel, 19 gallons of gasoline, 7 gallons of other products, 3 gallons split between heavy fuel oil and Liquified petroleum gases , and 2 gallons of heating oil. The total production of a barrel of crude into various products results in an increase to 45 barrels . Not all oils used as fuels are mineral oils, see biodiesel
Biodiesel
Biodiesel refers to a vegetable oil- or animal fat-based diesel fuel consisting of long-chain alkyl esters. Biodiesel is typically made by chemically reacting lipids with an alcohol....

 and vegetable oil fuel.

Chemical Feedstock


Crude oil can be refined into a wide variety of component hydrocarbons. Petrochemicals are the refined components of crude oil and the chemical products made from them. They are used as detergents, fertilizers, medicines, paints, plastics, synthetic fiber
Synthetic fiber
Synthetic fibers are the result of extensive research by scientists to improve on naturally occurring animal and plant fibers. In general, synthetic fibers are created by forcing, usually through extrusion, fiber forming materials through holes into the air, forming a thread...

s, and synthetic rubber
Synthetic rubber
Synthetic rubber is is any type of artificial elastomer, invariably a polymer. An elastomer is a material with the mechanical property that it can undergo much more elastic deformation under stress than most materials and still return to its previous size without permanent deformation...

.
Organic oils are another important chemical feedstock, especially in green chemistry
Green chemistry
Green chemistry, also called sustainable chemistry, is a philosophy of chemical research and engineering that encourages the design of products and processes that minimize the use and generation of hazardous substances...

.

See also

  • Emulsifier, a chemical which allows oil and water to mix
  • Lubrication
    Lubrication
    Lubrication is the process, or technique employed to reduce wear of one or both surfaces in close proximity, and moving relative to each another, by interposing a substance called lubricant between the surfaces to carry or to help carry the load between the opposing surfaces. The interposed...

  • 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...

    , a class of compounds with oil-like properties that are solid at common temperatures

External links