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53-697: An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water ) and lipophilic (mixes with other oils). Oils are usually flammable and surface active . Most oils are unsaturated lipids that are liquid at room temperature. The general definition of oil includes classes of chemical compounds that may be otherwise unrelated in structure, properties, and uses. Oils may be animal , vegetable , or petrochemical in origin, and may be volatile or non-volatile. They are used for food (e.g., olive oil ), fuel (e.g., heating oil ), medical purposes (e.g., mineral oil ), lubrication (e.g. motor oil ), and

106-737: A barrel of crude into various products results in an increase to 45 US gallons (37 imp gal; 170 L). In the 18th and 19th centuries, whale oil was commonly used for lamps, which was replaced with natural gas and then electricity. 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 fibers , and synthetic rubber . Organic oils are another important chemical feedstock, especially in green chemistry . Polarity (chemistry) Polar molecules must contain one or more polar bonds due to

159-527: A basis for the development of hybrid sunflowers to increase oil production. Analysis of the sunflower genome duplication – starting about 29 million years ago – revealed two major breeding traits: flowering time and oil metabolism, which can be cultivated to improve the commercialization of sunflower oil. In further analysis of the sunflower genome to reveal plant metabolism producing its oil, phytosterols and other phytochemicals , such as polyphenols , squalene , and terpenoids , were identified. After

212-448: A charged object is not based on polarity. The deflection occurs because of electrically charged droplets in the stream, which the charged object induces. A stream of water can also be deflected in a uniform electrical field, which cannot exert force on polar molecules. Additionally, after a stream of water is grounded, it can no longer be deflected. Weak deflection is even possible for nonpolar liquids. Sunflower oil Sunflower oil

265-438: A difference in electronegativity between the bonded atoms. Molecules containing polar bonds have no molecular polarity if the bond dipoles cancel each other out by symmetry. Polar molecules interact through dipole-dipole intermolecular forces and hydrogen bonds . Polarity underlies a number of physical properties including surface tension , solubility , and melting and boiling points. Not all atoms attract electrons with

318-412: A difference of zero. A completely polar bond is more correctly called an ionic bond , and occurs when the difference between electronegativities is large enough that one atom actually takes an electron from the other. The terms "polar" and "nonpolar" are usually applied to covalent bonds , that is, bonds where the polarity is not complete. To determine the polarity of a covalent bond using numerical means,

371-399: A dipole moment because, by definition, D point groups have two or multiple C n axes. Since C 1 , C s ,C ∞h C n and C n v point groups do not have a centre of inversion, horizontal mirror planes or multiple C n axis, molecules in one of those point groups will have dipole moment. Contrary to popular misconception, the electrical deflection of a stream of water from

424-492: A frying oil, it behaves as a typical vegetable oil, and is used in sunflower butter . Methods for cooking snack foods , such as potato chips or French fries , may use sunflower oil. Extraction of sunflower oil leaves behind the crushed seeds, typically referred to as seed meal, which is rich in protein and dietary fiber and used as an animal feed, fertilizer or fuel. Sunflower oil dietary supplements have been marketed for treatment of eczema , but research has shown it

477-537: A molar mass M = 18 and a boiling point of +100 °C, compared to nonpolar methane with M = 16 and a boiling point of –161 °C. Due to the polar nature of the water molecule itself, other polar molecules are generally able to dissolve in water. Most nonpolar molecules are water-insoluble ( hydrophobic ) at room temperature. Many nonpolar organic solvents , such as turpentine , are able to dissolve nonpolar substances. Polar compounds tend to have higher surface tension than nonpolar compounds. Polar liquids have

530-423: A net dipole. The dipole moment of water depends on its state. In the gas phase the dipole moment is ≈ 1.86 debye (D), whereas liquid water (≈ 2.95 D) and ice (≈ 3.09 D) are higher due to differing hydrogen-bonded environments. Other examples include sugars (like sucrose ), which have many polar oxygen–hydrogen (−OH) groups and are overall highly polar. If the bond dipole moments of the molecule do not cancel,

583-423: A positive charge (blue). The hydrogen fluoride , HF, molecule is polar by virtue of polar covalent bonds – in the covalent bond electrons are displaced toward the more electronegative fluorine atom. Ammonia , NH 3 , is a molecule whose three N−H bonds have only a slight polarity (toward the more electronegative nitrogen atom). The molecule has two lone electrons in an orbital that points towards

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636-438: A result of polar bonds due to differences in electronegativity as described above, or as a result of an asymmetric arrangement of nonpolar covalent bonds and non-bonding pairs of electrons known as a full molecular orbital . While the molecules can be described as "polar covalent", "nonpolar covalent", or "ionic", this is often a relative term, with one molecule simply being more polar or more nonpolar than another. However,

689-417: A symmetrical molecule such as bromine , Br 2 , has zero dipole moment, while near the other extreme, gas phase potassium bromide , KBr, which is highly ionic, has a dipole moment of 10.41 D. For polyatomic molecules, there is more than one bond. The total molecular dipole moment may be approximated as the vector sum of the individual bond dipole moments. Often bond dipoles are obtained by

742-416: A tendency to rise against gravity in a small diameter tube. Polar liquids have a tendency to be more viscous than nonpolar liquids. For example, nonpolar hexane is much less viscous than polar water. However, molecule size is a much stronger factor on viscosity than polarity, where compounds with larger molecules are more viscous than compounds with smaller molecules. Thus, water (small polar molecules)

795-446: A two equal vectors that oppose each other will cancel out. Any molecule with a centre of inversion ("i") or a horizontal mirror plane ("σ h ") will not possess dipole moments. Likewise, a molecule with more than one C n axis of rotation will not possess a dipole moment because dipole moments cannot lie in more than one dimension . As a consequence of that constraint, all molecules with dihedral symmetry (D n ) will not have

848-470: Is a dipole across the whole ozone molecule. A molecule may be nonpolar either when there is an equal sharing of electrons between the two atoms of a diatomic molecule or because of the symmetrical arrangement of polar bonds in a more complex molecule. For example, boron trifluoride (BF 3 ) has a trigonal planar arrangement of three polar bonds at 120°. This results in no overall dipole in the molecule. Carbon dioxide (CO 2 ) has two polar C=O bonds, but

901-423: Is a method that does not use chemical solvents to derive sunflower seed oil. Refining sunflower oil through solvent extraction, de-gumming, neutralization , and bleaching can make it more stable and suitable for high-temperature cooking, but doing so will also remove some of the oil's nutrients, flavor, color (resulting in a pale-yellow), free fatty acids, phospholipids, polyphenols, and phytosterols. Also, some of

954-431: Is a vector, parallel to the bond axis, pointing from minus to plus, as is conventional for electric dipole moment vectors. Chemists often draw the vector pointing from plus to minus. This vector can be physically interpreted as the movement undergone by electrons when the two atoms are placed a distance d apart and allowed to interact, the electrons will move from their free state positions to be localised more around

1007-426: Is calculated by multiplying the amount of charge separated and the distance between the charges. These dipoles within molecules can interact with dipoles in other molecules, creating dipole-dipole intermolecular forces . Bonds can fall between one of two extremes – completely nonpolar or completely polar. A completely nonpolar bond occurs when the electronegativities are identical and therefore possess

1060-425: Is less viscous than hexadecane (large nonpolar molecules). A polar molecule has a net dipole as a result of the opposing charges (i.e. having partial positive and partial negative charges) from polar bonds arranged asymmetrically. Water (H 2 O) is an example of a polar molecule since it has a slight positive charge on one side and a slight negative charge on the other. The dipoles do not cancel out, resulting in

1113-1200: Is no evidence that NASA has used whale oil. Some oils burn in liquid or aerosol form, generating light , and heat which can be used directly or converted into other forms of energy such as electricity or mechanical work. In order to obtain many fuel oils, crude oil is pumped from the ground and is shipped via oil tanker or a pipeline to an oil refinery . There, it is converted from crude oil to diesel fuel (petrodiesel), ethane (and other short-chain alkanes ), fuel oils (heaviest of commercial fuels, used in ships/furnaces), gasoline (petrol), jet fuel , kerosene , benzene (historically), and liquefied petroleum gas . A 42-US-gallon (35 imp gal; 160 L) barrel of crude oil produces approximately 10 US gallons (8.3 imp gal; 38 L) of diesel, 4 US gallons (3.3 imp gal; 15 L) of jet fuel, 19 US gallons (16 imp gal; 72 L) of gasoline, 7 US gallons (5.8 imp gal; 26 L) of other products, 3 US gallons (2.5 imp gal; 11 L) split between heavy fuel oil and liquified petroleum gases, and 2 US gallons (1.7 imp gal; 7.6 L) of heating oil. The total production of

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1166-403: Is no overall dipole in the molecule. The diatomic oxygen molecule (O 2 ) does not have polarity in the covalent bond because of equal electronegativity, hence there is no polarity in the molecule. Large molecules that have one end with polar groups attached and another end with nonpolar groups are described as amphiphiles or amphiphilic molecules. They are good surfactants and can aid in

1219-531: Is not medically effective. Sunflower oil can be used to run diesel engines when mixed with diesel in the tank. Due to the high levels of unsaturated fats, there is higher viscosity in cold temperatures. PEG-10 sunflower glycerides, a pale yellow liquid with a "slightly fatty" odor, are the polyethylene glycol derivative of the mono- and diglycerides derived from sunflower seed oil with an average of 10 moles of ethylene oxide . PEG-10 sunflower glycerides are commonly used in cosmetic formulations. In

1272-523: Is often considered a spiritually purifying agent and is used for anointing purposes. As a particular example, holy anointing oil has been an important ritual liquid for Judaism and Christianity . Oils have been consumed since ancient times. Oils hold lots of fats and medical properties. A good example is olive oil. Olive oil holds a lot of fats within it which is why it was also used in lighting in ancient Greece and Rome. So people would use it to bulk out food so they would have more energy to burn through

1325-643: Is preferred for lubricating clocks, because it does not evaporate, leaving dust, although its use was banned in the US in 1980. It is a long-running myth that spermaceti from whales has still been used in NASA projects such as the Hubble Space Telescope and the Voyager probe because of its extremely low freezing temperature. Spermaceti is not actually an oil, but a mixture mostly of wax esters, and there

1378-464: Is remote (and was unknown at the time of its discovery), and because it is obtained in the vicinity of rocks, underground traps, and sands. Mineral oil also refers to several specific distillates of crude oil. Several edible vegetable and animal oils, and also fats , are used for various purposes in cooking and food preparation. In particular, many foods are fried in oil much hotter than boiling water. Oils are also used for flavoring and for modifying

1431-419: Is the non-volatile oil pressed from the seeds of the sunflower ( Helianthus annuus ). Sunflower oil is commonly used in food as a frying oil , and in cosmetic formulations as an emollient . Sunflower oil is primarily composed of linoleic acid , a polyunsaturated fat , and oleic acid , a monounsaturated fat . Through selective breeding and manufacturing processes, oils of differing proportions of

1484-402: Is uneven – since the central atom has to share electrons with two other atoms, but each of the outer atoms has to share electrons with only one other atom, the central atom is more deprived of electrons than the others (the central atom has a formal charge of +1, while the outer atoms each have a formal charge of − 1 ⁄ 2 ). Since the molecule has a bent geometry, the result

1537-449: The 2022 Russian invasion of Ukraine , which has led to an over 50% drop in the availability of sunflower oil. Due to the shortages, many brands are reforming their recipes by switching to rapeseed oil to allow the production of their products to continue. Several varieties of sunflower oil seeds have been developed by standard plant breeding methods, mainly to vary the amounts of oleic acid and linoleic acid which, respectively, are

1590-444: The conversion factor of 10 statcoulomb being 0.208 units of elementary charge, so 1.0 debye results from an electron and a proton separated by 0.208 Å. A useful conversion factor is 1 D = 3.335 64 × 10  C m. For diatomic molecules there is only one (single or multiple) bond so the bond dipole moment is the molecular dipole moment, with typical values in the range of 0 to 11 D. At one extreme,

1643-603: The atoms, as electrons will be drawn closer to the atom with the higher electronegativity. Because electrons have a negative charge, the unequal sharing of electrons within a bond leads to the formation of an electric dipole : a separation of positive and negative electric charge. Because the amount of charge separated in such dipoles is usually smaller than a fundamental charge , they are called partial charges , denoted as δ+ ( delta plus) and δ− (delta minus). These symbols were introduced by Sir Christopher Ingold and Edith Hilda (Usherwood) Ingold in 1926. The bond dipole moment

Oil - Misplaced Pages Continue

1696-419: The day. Olive oil was also used to clean the body in this time as it would trap the moisture in the skin while pulling the grime to the surface. It was used as an ancient form of unsophisticated soap. It was applied on the skin then scrubbed off with a wooden stick pulling off the excess grime and creating a layer where new grime could form but be easily washed off in the water as oil is hydrophobic. Fish oils hold

1749-470: The difference between the electronegativity of the atoms is used. Bond polarity is typically divided into three groups that are loosely based on the difference in electronegativity between the two bonded atoms. According to the Pauling scale : Pauling based this classification scheme on the partial ionic character of a bond, which is an approximate function of the difference in electronegativity between

1802-520: The domestication of the sunflower (3000 BC) the Native Americans obtained and used oil from the seeds. In the modern era, sunflower oil was first used in food in 1830, in Russia. In 2021, world production of sunflower oil was 18.5   million tonnes , led by Russia and Ukraine, which together accounted for 55% of the total. In 2022, there was a global shortage of sunflower oil due to

1855-643: The fatty acids are produced. The expressed oil has a neutral taste profile. The oil contains a large amount of vitamin E . The Russian invasion of Ukraine that began in 2022 caused global prices of sunflower oil to increase by as much as 58% in a single month in 2022. Sunflower oil is mainly a triglyceride . The British Pharmacopoeia lists the following profile: Four types of sunflower oils with differing concentrations of fatty acids are produced through plant breeding and industrial processing: high-linoleic, high-oleic, mid-oleic, and high-stearic combined with high-oleic. A 2017 genome analysis provided

1908-487: The following properties are typical of such molecules. When comparing a polar and nonpolar molecule with similar molar masses, the polar molecule in general has a higher boiling point, because the dipole–dipole interaction between polar molecules results in stronger intermolecular attractions. One common form of polar interaction is the hydrogen bond , which is also known as the H-bond. For example, water forms H-bonds and has

1961-489: The formation of stable emulsions, or blends, of water and fats. Surfactants reduce the interfacial tension between oil and water by adsorbing at the liquid–liquid interface. Determining the point group is a useful way to predict polarity of a molecule. In general, a molecule will not possess dipole moment if the individual bond dipole moments of the molecule cancel each other out. This is because dipole moments are euclidean vector quantities with magnitude and direction, and

2014-476: The fourth apex of an approximately regular tetrahedron, as predicted by the VSEPR theory . This orbital is not participating in covalent bonding; it is electron-rich, which results in a powerful dipole across the whole ammonia molecule. In ozone (O 3 ) molecules, the two O−O bonds are nonpolar (there is no electronegativity difference between atoms of the same element). However, the distribution of other electrons

2067-435: The geometry of CO 2 is linear so that the two bond dipole moments cancel and there is no net molecular dipole moment; the molecule is nonpolar. Examples of household nonpolar compounds include fats, oil, and petrol/gasoline. In the methane molecule (CH 4 ) the four C−H bonds are arranged tetrahedrally around the carbon atom. Each bond has polarity (though not very strong). The bonds are arranged symmetrically so there

2120-547: The manufacture of many types of paints, plastics, and other materials. Specially prepared oils are used in some religious ceremonies and rituals as purifying agents. First attested in English 1176, the word oil comes from Old French oile , from Latin oleum , which in turn comes from the Greek ἔλαιον ( elaion ), "olive oil, oil" and that from ἐλαία ( elaia ), " olive tree", "olive fruit". The earliest attested forms of

2173-411: The modern economy. Crude oil originates from ancient fossilized organic materials , such as zooplankton and algae , which geochemical processes convert into oil. The name "mineral oil" is a misnomer , in that minerals are not the source of the oil—ancient plants and animals are. Mineral oil is organic. However, it is classified as "mineral oil" instead of as "organic oil" because its organic origin

Oil - Misplaced Pages Continue

2226-410: The molecule is polar. For example, the water molecule (H 2 O) contains two polar O−H bonds in a bent (nonlinear) geometry. The bond dipole moments do not cancel, so that the molecule forms a molecular dipole with its negative pole at the oxygen and its positive pole midway between the two hydrogen atoms. In the figure each bond joins the central O atom with a negative charge (red) to an H atom with

2279-476: The more electronegative atom. The SI unit for electric dipole moment is the coulomb–meter. This is too large to be practical on the molecular scale. Bond dipole moments are commonly measured in debyes , represented by the symbol D, which is obtained by measuring the charge δ {\displaystyle \delta } in units of 10 statcoulomb and the distance d in Angstroms . Based on

2332-751: The omega-3 fatty acid. This fatty acid helps with inflammation and reduces fat in the bloodstream.   Color pigments are easily suspended in oil, making it suitable as a supporting medium for paints . The oldest known extant oil paintings date from 650 AD. Oils are used as coolants in oil cooling , for instance in electric transformers . Heat transfer oils are used both as coolants (see oil cooling ), for heating (e.g. in oil heaters ) and in other applications of heat transfer. Given that they are non-polar, oils do not easily adhere to other substances. This makes them useful as lubricants for various engineering purposes. Mineral oils are more commonly used as machine lubricants than biological oils are. Whale oil

2385-422: The polyunsaturated fatty acids will be converted into trans fat due to the high temperatures involved in the process. Unrefined sunflower oil is less heat-stable (and therefore well-suited to dishes that are raw, or cooked at low temperatures), but it will retain more of its original nutrient content, flavor, and color (light-amber). Refined sunflower oil is used for low-to-extremely-high-temperature cooking. As

2438-1027: The predominant monounsaturated and polyunsaturated fats in sunflower oil. Sunflower oil is 100% fat , and is a rich source of vitamin E (tables). Sunflower oil is liquid at room temperature. The refined oil is clear and slightly amber-colored with a slightly fatty odour. Because sunflower oil is primarily composed of less-stable polyunsaturated and monounsaturated fatty acids, it can be particularly susceptible to degradation by heat, air, and light, which trigger and accelerate oxidation . Keeping sunflower oil at low temperatures during manufacturing and storage can help minimize rancidity and nutrient loss—as can storage in bottles that are made of either darkly-colored glass, or plastic that has been treated with an ultraviolet light protectant. Sunflower oil can be extracted using chemical solvents (e.g., hexane ), or expeller pressing (i.e., squeezed directly from sunflower seeds by crushing them). "Cold-pressing" (or expeller pressing) sunflower seeds under low-temperature conditions

2491-484: The reverse process: a known total dipole of a molecule can be decomposed into bond dipoles. This is done to transfer bond dipole moments to molecules that have the same bonds, but for which the total dipole moment is not yet known. The vector sum of the transferred bond dipoles gives an estimate for the total (unknown) dipole of the molecule. A molecule is composed of one or more chemical bonds between molecular orbitals of different atoms. A molecule may be polar either as

2544-409: The same force. The amount of "pull" an atom exerts on its electrons is called its electronegativity . Atoms with high electronegativities – such as fluorine , oxygen , and nitrogen  – exert a greater pull on electrons than atoms with lower electronegativities such as alkali metals and alkaline earth metals . In a bond, this leads to unequal sharing of electrons between

2597-420: The texture of foods (e.g. stir fry ). Cooking oils are derived either from animal fat, as butter , lard and other types, or plant oils from olive , maize , sunflower and many other species. 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 . Oil has been used throughout history as a religious medium. It

2650-440: The two bonded atoms. He estimated that a difference of 1.7 corresponds to 50% ionic character, so that a greater difference corresponds to a bond which is predominantly ionic. As a quantum-mechanical description, Pauling proposed that the wave function for a polar molecule AB is a linear combination of wave functions for covalent and ionic molecules: ψ = aψ(A:B) + bψ(A B ). The amount of covalent and ionic character depends on

2703-415: The values of the squared coefficients a and b . The bond dipole moment uses the idea of electric dipole moment to measure the polarity of a chemical bond within a molecule . It occurs whenever there is a separation of positive and negative charges. The bond dipole μ is given by: The bond dipole is modeled as δ  — δ with a distance d between the partial charges δ and δ . It

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2756-532: The way that they are made by an organism, their chemical structure and their limited solubility in water compared to oils. They have a high carbon and hydrogen content and are considerably lacking in oxygen compared to other organic compounds and minerals; they tend to be relatively nonpolar molecules, but may include both polar and nonpolar regions as in the case of phospholipids and steroids. Crude oil, or petroleum , and its refined components, collectively termed petrochemicals , are crucial resources in

2809-785: The word are the Mycenaean Greek 𐀁𐀨𐀺 , e-ra-wo and 𐀁𐁉𐀺 , e-rai-wo , written in the Linear B syllabic script. Organic oils are produced in remarkable diversity by plants, animals, and other organisms through natural metabolic processes. Lipid is the scientific term for the fatty acids , steroids 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 proteins , waxes (class of compounds with oil-like properties that are solid at common temperatures) and alkaloids . Lipids can be classified by

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