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Octane
Octane is a hydrocarbon and also an alkane with the chemical formula C8H18, and the condensed structural formula CH3(CH2)6CH3. Octane has many structural isomers that differ by the location of branching in the carbon chain. One of these isomers, 2,2,4-Trimethylpentane, 2,2,4-trimethylpentane (commonly called iso-octane), is used as one of the standard values in the octane rating scale. Octane is a component of gasoline and petroleum. Under standard temperature and pressure, octane is an odorless, colorless liquid. Like other short-chained alkanes with a low molecular weight, it is Volatility (chemistry), volatile, flammable, and toxic. Octane is 1.2 to 2 times more toxic than heptane. Isomers N-octane has 23 Structural isomers, constitutional isomers. 8 of these isomers have one stereocenter; 3 of them have two stereocenters. Achiral isomers: * 2-Methylheptane * 4-Methylheptane * 3-Ethylhexane * 2,2-Dimethylhexane * 2,5-Dimethylhexane * 3,4-Dimethylhexane, (''meso'')-3,4-Dime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octane Rating
An octane rating, or octane number, is a standard measure of a liquid fuel, fuel's ability to withstand Compression ratio, compression in an internal combustion engine without causing engine knocking. The higher the octane number, the more compression the fuel can withstand before detonating. Octane rating does not relate directly to the power output or the energy content of the fuel per unit mass or volume, but simply indicates the resistance to detonating under pressure without a spark. Whether a higher octane fuel improves or impairs an engine's performance depends on the design of the engine. In broad terms, fuels with a higher octane rating are used in higher-compression Petrol engine, gasoline engines, which may yield higher power for these engines. The added power in such cases comes from the way the engine is designed to compress the air/fuel mixture, and not directly from the rating of the gasoline. In contrast, fuels with lower octane (but higher cetane numbers) are idea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gasoline
Gasoline ( North American English) or petrol ( Commonwealth English) is a petrochemical product characterized as a transparent, yellowish, and flammable liquid normally used as a fuel for spark-ignited internal combustion engines. When formulated as a fuel for engines, gasoline is chemically composed of organic compounds derived from the fractional distillation of petroleum and later chemically enhanced with gasoline additives. It is a high-volume profitable product produced in crude oil refineries. The ability of a particular gasoline blend to resist premature ignition (which causes knocking and reduces efficiency in reciprocating engines) is measured by its octane rating. Tetraethyl lead was once widely used to increase the octane rating but is not used in modern automotive gasoline due to the health hazard. Aviation, off-road motor vehicles, and racing car engines still use leaded gasolines. Other substances are frequently added to gasoline to improve chemical st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octane Stereo Isomers 10 3 4 Dimethylhexane
Octane is a hydrocarbon and also an alkane with the chemical formula C8H18, and the condensed structural formula CH3(CH2)6CH3. Octane has many structural isomers that differ by the location of branching in the carbon chain. One of these isomers, 2,2,4-trimethylpentane (commonly called iso-octane), is used as one of the standard values in the octane rating scale. Octane is a component of gasoline and petroleum. Under standard temperature and pressure, octane is an odorless, colorless liquid. Like other short-chained alkanes with a low molecular weight, it is volatile, flammable, and toxic. Octane is 1.2 to 2 times more toxic than heptane. Isomers N-octane has 23 constitutional isomers. 8 of these isomers have one stereocenter; 3 of them have two stereocenters. Achiral isomers: * 2-Methylheptane * 4-Methylheptane * 3-Ethylhexane * 2,2-Dimethylhexane * 2,5-Dimethylhexane * (''meso'')-3,4-Dimethylhexane * 3,3-Dimethylhexane * 3-Ethyl-2-methylpentane * 3-Ethyl-3-methylpent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2,2,4-Trimethylpentane
2,2,4-Trimethylpentane, also known as isooctane or iso-octane, is an organic compound with the formula (CH3)3CCH2CH(CH3)2. It is one of several isomers of octane (C8H18). This particular isomer is the standard 100 point on the octane rating scale (the zero point is ''n''-heptane). It is an important component of gasoline, frequently used in relatively large proportions (around 10%) to increase the knock resistance of fuel. Strictly speaking, if the standard meaning of ‘iso’ is followed, the name ''isooctane'' should be reserved for the isomer 2-methylheptane. However, 2,2,4-trimethylpentane is by far the most important isomer of octane and historically it has been assigned this name. Production Isooctane is produced on a massive scale in the petroleum industry by alkylation of isobutene with isobutane. This process is conducted in alkylation units in the presence of acid catalysts. : It can also be produced from isobutylene by dimerization using an Amberlyst cataly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkane
In organic chemistry, an alkane, or paraffin (a historical trivial name that also has other meanings), is an acyclic saturated hydrocarbon. In other words, an alkane consists of hydrogen and carbon atoms arranged in a tree structure in which all the carbon–carbon bonds are single. Alkanes have the general chemical formula . The alkanes range in complexity from the simplest case of methane (), where ''n'' = 1 (sometimes called the parent molecule), to arbitrarily large and complex molecules, like hexacontane () or 4-methyl-5-(1-methylethyl) octane, an isomer of dodecane (). The International Union of Pure and Applied Chemistry (IUPAC) defines alkanes as "acyclic branched or unbranched hydrocarbons having the general formula , and therefore consisting entirely of hydrogen atoms and saturated carbon atoms". However, some sources use the term to denote ''any'' saturated hydrocarbon, including those that are either monocyclic (i.e. the cycloalkanes) or polycycl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heptane
Heptane or ''n''-heptane is the straight-chain alkane with the chemical formula H3C(CH2)5CH3 or C7H16. When used as a test fuel component in anti-knock test engines, a 100% heptane fuel is the zero point of the octane rating scale (the 100 point is 100% iso-octane). Octane number equates to the anti-knock qualities of a comparison mixture of heptane and iso-octane which is expressed as the percentage of iso-octane in heptane, and is listed on pumps for gasoline (petrol) dispensed globally. History Normal heptane was discovered in 1862 by Carl Schorlemmer, who, while analyzing pyrolysis products of the cannel coal mined in Wigan, identified, separated by fractional distillation and studied a series of liquid hydrocarbons inert to nitric and sulfuric acids. One of them, which he called hydride of heptyl (oenanthyl), had an empirical formula of C7H16, density of 0.709 at 18 °C and boiled between 98 and 99 °C. In the next year he identified the same compound in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butane
Butane () is an alkane with the formula C4H10. Butane exists as two isomers, ''n''-butane with connectivity and iso-butane with the formula . Both isomers are highly flammable, colorless, easily liquefied gases that quickly vaporize at room temperature and pressure. Butanes are a trace components of natural gases (NG gases). The other hydrocarbons in NG include propane, ethane, and especially methane, which are more abundant. Liquefied petroleum gas is a mixture of propane and some butanes. The name butane comes from the root but- (from butyric acid, named after the Greek word for butter) and the suffix -ane (for organic compounds). History The first synthesis of butane was accidentally achieved by British chemist Edward Frankland in 1849 from ethyl iodide and zinc, but he had not realized that the ethyl radical dimerized and misidentified the substance. It was discovered in crude petroleum in 1864 by Edmund Ronalds, who was the first to describe its proper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2-Methylheptane
2-Methylheptane is a branched-chain alkane and an isomer of octane. It is an heptane molecule with a methyl group attached to its second atom. It is a flammable colorless liquid used as fuel. If the standard definition of the prefix "iso-" is strictly used then 2-methylheptane can be called "Isooctane". However this name is usually used for another much more important isomer of octane 2,2,4-trimethylpentane 2,2,4-Trimethylpentane, also known as isooctane or iso-octane, is an organic compound with the formula (CH3)3CCH2CH(CH3)2. It is one of several isomers of octane (C8H18). This particular isomer is the standard 100 point on the octane rating scale .... References External links *Chemical and physical properties table {{DEFAULTSORT:Methylheptane, 2- Alkanes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2,5-Dimethylhexane
2,5-Dimethylhexane is a branched alkane used in the aviation industry in low revolutions per minute helicopters. As an isomer of octane, the boiling point The boiling point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid and the liquid changes into a vapor. The boiling point of a liquid varies depending upon the surrounding envi ... is very close to that of octane, but can in pure form be slightly lower. 2,5-Dimethylhexane is moderately toxic. References {{DEFAULTSORT:Dimethylhexane, 2,5- Alkanes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentane
Pentane is an organic compound with the chemical formula, formula C5H12—that is, an alkane with five carbon atoms. The term may refer to any of three structural isomerism, structural isomers, or to a mixture of them: in the IUPAC nomenclature, however, pentane means exclusively the ''n''-pentane isomer, in which case pentanes refers to a mixture of them; the other two are called isopentane (methylbutane) and neopentane (dimethylpropane). Cyclopentane is not an isomer of pentane because it has only 10 hydrogen atoms where pentane has 12. Pentanes are components of some fuels and are employed as specialty solvents in the laboratory. Their properties are very similar to those of butanes and hexanes. History Normal pentane was discovered in 1862 by Carl Schorlemmer, who, while analyzing pyrolysis products of the cannel coal mined in Wigan, identified, separated by fractional distillation and studied a series of liquid hydrocarbons inert to Nitric acid, nitric and Sulfuric acid, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octonium
In chemistry, a carbonium ion is a cation that has a Coordination number, pentacoordinated carbon atom. They are a type of carbocation. In older literature, the name "carbonium ion" was used for what is today called carbenium ion, carbenium. Carbonium ions charge is delocalized in three-center, two-electron bonds. The more stable members are often bi- or polycyclic. 2-Norbornyl cation The 2-Norbornyl cation , 2-norbornyl cation is one of the best-characterized carbonium ions. It is the prototype for non-classical ions. As indicated first by low-temperature NMR spectroscopy and confirmed by X-ray crystallography, it has a symmetric structure with an RCH2+ group bonded to an alkene group, stabilized by a bicyclic structure. Cyclopropylmethyl cation A non-classical structure for is supported by substantial experimental evidence from solvolysis experiments and NMR studies. One or both of two structures, the cyclopropylcarbinyl cation and the bicyclobutonium cation, were invoked ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
