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82-454: When material is heated enough, it begins to break down into smaller compounds, including flammable or even explosive gas, typically hydrocarbons . This is called pyrolysis , and does not require oxygen. If oxygen is also provided, then the hydrocarbons can combust, starting a fire. If material undergoing pyrolysis is later given sufficient oxygen, the hydrocarbons will ignite, and therefore, combustion takes place. A backdraft can occur when

164-510: A =4), thiols (13), malonates (13), alcohols (17), aldehydes (20), nitriles (25), esters (25), then amines (35). Amines are very basic, and are great nucleophiles/attackers. The aliphatic hydrocarbons are subdivided into three groups of homologous series according to their state of saturation : The rest of the group is classified according to the functional groups present. Such compounds can be "straight-chain", branched-chain or cyclic. The degree of branching affects characteristics, such as

246-579: A hydrocarbon is an organic compound consisting entirely of hydrogen and carbon . Hydrocarbons are examples of group 14 hydrides . Hydrocarbons are generally colourless and hydrophobic ; their odor is usually faint, and may be similar to that of gasoline or lighter fluid . They occur in a diverse range of molecular structures and phases: they can be gases (such as methane and propane ), liquids (such as hexane and benzene ), low melting solids (such as paraffin wax and naphthalene ) or polymers (such as polyethylene and polystyrene ). In

328-708: A molar mass less than approximately 1000 g/mol. Fullerenes and carbon nanotubes , carbon compounds with spheroidal and tubular structures, have stimulated much research into the related field of materials science . The first fullerene was discovered in 1985 by Sir Harold W. Kroto of the United Kingdom and by Richard E. Smalley and Robert F. Curl Jr., of the United States. Using a laser to vaporize graphite rods in an atmosphere of helium gas, these chemists and their assistants obtained cagelike molecules composed of 60 carbon atoms (C60) joined by single and double bonds to form

410-546: A branch of organic chemistry. Although the history of biochemistry might be taken to span some four centuries, fundamental understanding of the field only began to develop in the late 19th century and the actual term biochemistry was coined around the start of 20th century. Research in the field increased throughout the twentieth century, without any indication of slackening in the rate of increase, as may be verified by inspection of abstraction and indexing services such as BIOSIS Previews and Biological Abstracts , which began in

492-423: A broad range of industrial and commercial products including, among (many) others: plastics , synthetic rubber , organic adhesives , and various property-modifying petroleum additives and catalysts . The majority of chemical compounds occurring in biological organisms are carbon compounds, so the association between organic chemistry and biochemistry is so close that biochemistry might be regarded as in essence

574-506: A carbon lattice, and that the detailed patterns of atomic bonding could be discerned by skillful interpretations of appropriate chemical reactions. The era of the pharmaceutical industry began in the last decade of the 19th century when the German company, Bayer , first manufactured acetylsalicylic acid—more commonly known as aspirin . By 1910 Paul Ehrlich and his laboratory group began developing arsenic-based arsphenamine , (Salvarsan), as

656-415: A class of hydrocarbons called biopolymer polyisoprenoids present in the latex of various species of plants, which is the basis for making rubber . Biologists usually classify the above-mentioned biomolecules into four main groups, i.e., proteins, lipids, carbohydrates, and nucleic acids. Petroleum and its derivatives are considered organic molecules, which is consistent with the fact that this oil comes from

738-462: A combination of luck and preparation for unexpected observations. The latter half of the 19th century however witnessed systematic studies of organic compounds. The development of synthetic indigo is illustrative. The production of indigo from plant sources dropped from 19,000 tons in 1897 to 1,000 tons by 1914 thanks to the synthetic methods developed by Adolf von Baeyer . In 2002, 17,000 tons of synthetic indigo were produced from petrochemicals . In

820-414: A common thermoplastic material. Addition reactions apply to alkenes and alkynes. It is because they add reagents that they are called unsaturated. In this reaction a variety of reagents add "across" the pi-bond(s). Chlorine, hydrogen chloride, water , and hydrogen are illustrative reagents. Polymerization is a form of addition. Alkenes and some alkynes also undergo polymerization by opening of

902-419: A common reaction is a substitution reaction written as: where X is some functional group and Nu is a nucleophile . The number of possible organic reactions is infinite. However, certain general patterns are observed that can be used to describe many common or useful reactions. Each reaction has a stepwise reaction mechanism that explains how it happens in sequence—although the detailed description of steps

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984-437: A compartment fire has little or no ventilation. Due to this, little or no oxygen can flow into the compartment. Then, because fires reduce oxygen, the oxygen concentration decreases. When the oxygen concentration becomes too low to support combustion, some or all of the combustion switches to pyrolysis. However, the hydrocarbons and smoke (primarily particulate matter ) remain at a temperature hot enough to auto-ignite . If oxygen

1066-411: A crack, they generally evacuate immediately, because this is a strong indication that a backdraft is imminent. Due to pressure differences, puffs of smoke are sometimes drawn back into the enclosed space from which they emanated, which is how the term backdraft originated. Backdrafts are very dangerous, often surprising even experienced firefighters. The most common tactic used by firefighters to defuse

1148-426: A double bond between carbon atoms are sometimes referred to as 'olefins'. The predominant use of hydrocarbons is as a combustible fuel source. Methane is the predominant component of natural gas. C through C alkanes, alkenes, cycloalkanes, and aromatic hydrocarbons are the main components of gasoline , naphtha , jet fuel , and specialized industrial solvent mixtures. With the progressive addition of carbon units,

1230-565: A hollow sphere with 12 pentagonal and 20 hexagonal faces—a design that resembles a football, or soccer ball. In 1996 the trio was awarded the Nobel Prize for their pioneering efforts. The C60 molecule was named buckminsterfullerene (or, more simply, the buckyball) after the American architect R. Buckminster Fuller, whose geodesic dome is constructed on the same structural principles. Organic compounds containing bonds of carbon to nitrogen, oxygen and

1312-427: A lower p K a on another molecule (intermolecular) or within the same molecule (intramolecular). Any group with a net acidic p K a that gets within range, such as an acyl or carbonyl group is fair game. Since the likelihood of being attacked decreases with an increase in p K a , acyl chloride components with the lowest measured p K a values are most likely to be attacked, followed by carboxylic acids (p K

1394-484: A melting point, boiling point, solubility, and index of refraction. Qualitative properties include odor, consistency, and color. Organic compounds typically melt and many boil. In contrast, while inorganic materials generally can be melted, many do not boil, and instead tend to degrade. In earlier times, the melting point (m.p.) and boiling point (b.p.) provided crucial information on the purity and identity of organic compounds. The melting and boiling points correlate with

1476-475: A novel compound is a problem-solving task, where a synthesis is designed for a target molecule by selecting optimal reactions from optimal starting materials. Complex compounds can have tens of reaction steps that sequentially build the desired molecule. The synthesis proceeds by utilizing the reactivity of the functional groups in the molecule. For example, a carbonyl compound can be used as a nucleophile by converting it into an enolate , or as an electrophile ;

1558-446: A potential backdraft is to ventilate a room from its highest point, allowing the heat and smoke to escape without igniting. Common signs of imminent backdraft include a sudden inrush of air upon creating an opening into a closed compartment, no visible signs of flame in a hot compartment (fire above its upper flammability limit ), "pulsing" smoke plumes from openings, and auto-ignition of hot gases at openings as they mix with oxygen in

1640-552: A respectfully natural environment, or without human intervention. Biomolecular chemistry is a major category within organic chemistry which is frequently studied by biochemists . Many complex multi-functional group molecules are important in living organisms. Some are long-chain biopolymers , and these include peptides , DNA , RNA and the polysaccharides such as starches in animals and celluloses in plants. The other main classes are amino acids (monomer building blocks of peptides and proteins), carbohydrates (which includes

1722-529: A single C–C bond it is alkane metathesis , for a double C–C bond it is alkene metathesis (olefin metathesis), and for a triple C–C bond it is alkyne metathesis . The vast majority of hydrocarbons found on Earth occur in crude oil , petroleum, coal , and natural gas. Since thousands of years they have been exploited and used for a vast range of purposes. Petroleum ( lit.   ' rock oil ' ) and coal are generally thought to be products of decomposition of organic matter. Coal, in contrast to petroleum,

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1804-468: A two neutral radical atoms ( homolytic fission ). all the way to CCl 4 ( carbon tetrachloride ) all the way to C 2 Cl 6 ( hexachloroethane ) Aromatic compounds, almost uniquely for hydrocarbons, undergo substitution reactions. The chemical process practiced on the largest scale is the reaction of benzene and ethene to give ethylbenzene : The resulting ethylbenzene is dehydrogenated to styrene and then polymerized to manufacture polystyrene ,

1886-686: A variety of chemical tests, called "wet methods", but such tests have been largely displaced by spectroscopic or other computer-intensive methods of analysis. Listed in approximate order of utility, the chief analytical methods are: Traditional spectroscopic methods such as infrared spectroscopy , optical rotation , and UV/VIS spectroscopy provide relatively nonspecific structural information but remain in use for specific applications. Refractive index and density can also be important for substance identification. The physical properties of organic compounds typically of interest include both quantitative and qualitative features. Quantitative information includes

1968-514: A wide range of biochemical compounds such as alkaloids , vitamins, steroids, and nucleic acids (e.g. DNA, RNA). Rings can fuse with other rings on an edge to give polycyclic compounds . The purine nucleoside bases are notable polycyclic aromatic heterocycles. Rings can also fuse on a "corner" such that one atom (almost always carbon) has two bonds going to one ring and two to another. Such compounds are termed spiro and are important in several natural products . One important property of carbon

2050-469: Is a subdiscipline within chemistry involving the scientific study of the structure, properties, and reactions of organic compounds and organic materials , i.e., matter in its various forms that contain carbon atoms . Study of structure determines their structural formula . Study of properties includes physical and chemical properties , and evaluation of chemical reactivity to understand their behavior. The study of organic reactions includes

2132-696: Is also potential to harvest hydrocarbons from plants like Euphorbia lathyris and E. tirucalli as an alternative and renewable energy source for vehicles that use diesel. Furthermore, endophytic bacteria from plants that naturally produce hydrocarbons have been used in hydrocarbon degradation in attempts to deplete hydrocarbon concentration in polluted soils. Saturated hydrocarbons are notable for their inertness. Unsaturated hydrocarbons (alkanes, alkenes and aromatic compounds) react more readily, by means of substitution, addition, polymerization. At higher temperatures they undergo dehydrogenation, oxidation and combustion. The cracking of saturated hydrocarbons

2214-400: Is called autoxidation , begins with the formation of hydroperoxides (ROOH). Combustion of hydrocarbons is currently the main source of the world's energy for electric power generation , heating (such as home heating), and transportation. Often this energy is used directly as heat such as in home heaters, which use either petroleum or natural gas . The hydrocarbon is burnt and the heat

2296-420: Is conferred by the presence of 4n + 2 delocalized pi electrons, where n is an integer. Particular instability ( antiaromaticity ) is conferred by the presence of 4n conjugated pi electrons. The characteristics of the cyclic hydrocarbons are again altered if heteroatoms are present, which can exist as either substituents attached externally to the ring (exocyclic) or as a member of the ring itself (endocyclic). In

2378-477: Is estimated at more than 58 million metric tons, which will increase to 60 million tons in 2022. Hydrocarbons are also prevalent in nature. Some eusocial arthropods, such as the Brazilian stingless bee, Schwarziana quadripunctata , use unique cuticular hydrocarbon "scents" in order to determine kin from non-kin. This hydrocarbon composition varies between age, sex, nest location, and hierarchal position. There

2460-480: Is not always clear from a list of reactants alone. The stepwise course of any given reaction mechanism can be represented using arrow pushing techniques in which curved arrows are used to track the movement of electrons as starting materials transition through intermediates to final products. Synthetic organic chemistry is an applied science as it borders engineering , the "design, analysis, and/or construction of works for practical purposes". Organic synthesis of

2542-419: Is possible. Hydrocarbons are generally of low toxicity, hence the widespread use of gasoline and related volatile products. Aromatic compounds such as benzene and toluene are narcotic and chronic toxins, and benzene in particular is known to be carcinogenic . Certain rare polycyclic aromatic compounds are carcinogenic. Hydrocarbons are highly flammable . Organic chemistry Organic chemistry

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2624-463: Is richer in carbon and poorer in hydrogen. Natural gas is the product of methanogenesis . A seemingly limitless variety of compounds comprise petroleum, hence the necessity of refineries. These hydrocarbons consist of saturated hydrocarbons, aromatic hydrocarbons, or combinations of the two. Missing in petroleum are alkenes and alkynes. Their production requires refineries. Petroleum-derived hydrocarbons are mainly consumed for fuel, but they are also

2706-444: Is simple and unambiguous. In this system, the endpoints and intersections of each line represent one carbon, and hydrogen atoms can either be notated explicitly or assumed to be present as implied by tetravalent carbon. By 1880 an explosion in the number of chemical compounds being discovered occurred assisted by new synthetic and analytical techniques. Grignard described the situation as "chaos le plus complet" (complete chaos) due to

2788-451: Is systematically named (6a R ,9 R )- N , N -diethyl-7-methyl-4,6,6a,7,8,9-hexahydroindolo-[4,3- fg ] quinoline-9-carboxamide. With the increased use of computing, other naming methods have evolved that are intended to be interpreted by machines. Two popular formats are SMILES and InChI . Organic molecules are described more commonly by drawings or structural formulas , combinations of drawings and chemical symbols. The line-angle formula

2870-456: Is that it readily forms chains, or networks, that are linked by carbon-carbon (carbon-to-carbon) bonds. The linking process is called polymerization , while the chains, or networks, are called polymers . The source compound is called a monomer . Two main groups of polymers exist synthetic polymers and biopolymers . Synthetic polymers are artificially manufactured, and are commonly referred to as industrial polymers . Biopolymers occur within

2952-616: Is the main industrial route to alkenes and alkyne . These reactions require heterogeneous catalysts and temperatures >500 °C. Widely practice conversions of hydrocarbons involves their reaction with oxygen. In the presence of excess oxygen, hydrocarbons combust. With, however, careful conditions, which have been optimized for many years, partial oxidation results. Useful compounds can obtained in this way: maleic acid from butane , terephthalic acid from xylenes , acetone together with phenol from cumene (isopropylbenzene), and cyclohexanone from cyclohexane]]. The process, which

3034-398: Is the paucity of enzymes that act on them. Nonetheless, the area has received regular attention. Bacteria in the gabbroic layer of the ocean's crust can degrade hydrocarbons; but the extreme environment makes research difficult. Other bacteria such as Lutibacterium anuloederans can also degrade hydrocarbons. Mycoremediation or breaking down of hydrocarbon by mycelium and mushrooms

3116-402: Is then re-introduced to the compartment, e.g. by opening a door or window to a closed room, while the gasses are still hot enough to auto-ignite, combustion will restart, often abruptly or even explosively, as the gasses are heated by the combustion and expand rapidly because of the rapidly increasing temperature, combined with the energy released from combustion. The colour and movement of smoke

3198-413: Is typically taught at the college or university level. It is considered a very challenging course, but has also been made accessible to students. Before the 18th century, chemists generally believed that compounds obtained from living organisms were endowed with a vital force that distinguished them from inorganic compounds . According to the concept of vitalism (vital force theory), organic matter

3280-420: Is used by firefighters to infer fire conditions, including the risk of backdraft. Characteristic warning signs of a backdraft include yellow or brown smoke, smoke which exits small holes in puffs (a sort of breathing effect) and is often found around the edges of doors and windows, and windows which appear brown or black when viewed from the exterior due to soot from incomplete combustion. This is an indication that

3362-597: Is used to heat water, which is then circulated. A similar principle is used to create electrical energy in power plants . Both saturated and unsaturated hydrocarbons undergo this process. Common properties of hydrocarbons are the facts that they produce steam, carbon dioxide and heat during combustion and that oxygen is required for combustion to take place. The simplest hydrocarbon, methane , burns as follows: In inadequate supply of air, carbon black and water vapour are formed: And finally, for any linear alkane of n carbon atoms, Partial oxidation characterizes

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3444-535: The Solar System . Lakes of liquid methane and ethane have been found on Titan , Saturn 's largest moon, as confirmed by the Cassini–Huygens space probe. Hydrocarbons are also abundant in nebulae forming polycyclic aromatic hydrocarbon compounds. Burning hydrocarbons as fuel, which produces carbon dioxide and water , is a major contributor to anthropogenic global warming . Hydrocarbons are introduced into

3526-412: The autoignition temperature of the combustible material and gases in an enclosure. Flashovers according to this narrower definition, i.e. those caused by rising temperatures, would not be considered backdrafts since backdrafts are caused by the introduction of oxygen into an enclosed space with conditions already suitable for ignition, and are thus caused by chemical change. Backdrafts were publicized by

3608-476: The chemical synthesis of natural products , drugs , and polymers , and study of individual organic molecules in the laboratory and via theoretical ( in silico ) study. The range of chemicals studied in organic chemistry includes hydrocarbons (compounds containing only carbon and hydrogen ) as well as compounds based on carbon, but also containing other elements, especially oxygen , nitrogen , sulfur , phosphorus (included in many biochemicals ) and

3690-435: The cycloalkenes and the cycloalkynes do. Aromatic hydrocarbons contain conjugated double bonds. This means that every carbon atom in the ring is sp2 hybridized, allowing for added stability. The most important example is benzene , the structure of which was formulated by Kekulé who first proposed the delocalization or resonance principle for explaining its structure. For "conventional" cyclic compounds, aromaticity

3772-420: The electron affinity of key atoms, bond strengths and steric hindrance . These factors can determine the relative stability of short-lived reactive intermediates , which usually directly determine the path of the reaction. The basic reaction types are: addition reactions , elimination reactions , substitution reactions , pericyclic reactions , rearrangement reactions and redox reactions . An example of

3854-454: The fossil fuel industries, hydrocarbon refers to naturally occurring petroleum , natural gas and coal , or their hydrocarbon derivatives and purified forms. Combustion of hydrocarbons is the main source of the world's energy. Petroleum is the dominant raw-material source for organic commodity chemicals such as solvents and polymers. Most anthropogenic (human-generated) emissions of greenhouse gases are either carbon dioxide released by

3936-407: The halogens . Organometallic chemistry is the study of compounds containing carbon– metal bonds. In addition, contemporary research focuses on organic chemistry involving other organometallics including the lanthanides , but especially the transition metals zinc, copper, palladium , nickel, cobalt, titanium and chromium. Organic compounds form the basis of all earthly life and constitute

4018-541: The octane number or cetane number in petroleum chemistry. Both saturated ( alicyclic ) compounds and unsaturated compounds exist as cyclic derivatives. The most stable rings contain five or six carbon atoms, but large rings (macrocycles) and smaller rings are common. The smallest cycloalkane family is the three-membered cyclopropane ((CH 2 ) 3 ). Saturated cyclic compounds contain single bonds only, whereas aromatic rings have an alternating (or conjugated) double bond. Cycloalkanes do not contain multiple bonds, whereas

4100-618: The 1920s as a single annual volume, but has grown so drastically that by the end of the 20th century it was only available to the everyday user as an online electronic database . Since organic compounds often exist as mixtures , a variety of techniques have also been developed to assess purity; chromatography techniques are especially important for this application, and include HPLC and gas chromatography . Traditional methods of separation include distillation , crystallization , evaporation , magnetic separation and solvent extraction . Organic compounds were traditionally characterized by

4182-487: The 1991 movie Backdraft , in which a serial arsonist in Chicago uses them as a means of assassinating conspirators in a scam. In the film adaptation of Stephen King's 1408 , the protagonist Mike Enslin induces one as a last-ditch effort to kill the room. The term is also used and is the title of a scene in the 2012 video game Root Double: Before Crime * After Days . Hydrocarbon In organic chemistry ,

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4264-486: The burning of fossil fuels , or methane released from the handling of natural gas or from agriculture. As defined by the International Union of Pure and Applied Chemistry 's nomenclature of organic chemistry , hydrocarbons are classified as follows: The term 'aliphatic' refers to non-aromatic hydrocarbons. Saturated aliphatic hydrocarbons are sometimes referred to as 'paraffins'. Aliphatic hydrocarbons containing

4346-495: The case of the latter, the ring is termed a heterocycle . Pyridine and furan are examples of aromatic heterocycles while piperidine and tetrahydrofuran are the corresponding alicyclic heterocycles. The heteroatom of heterocyclic molecules is generally oxygen, sulfur, or nitrogen, with the latter being particularly common in biochemical systems. Heterocycles are commonly found in a wide range of products including aniline dyes and medicines. Additionally, they are prevalent in

4428-473: The combination of the two is called the aldol reaction . Designing practically useful syntheses always requires conducting the actual synthesis in the laboratory. The scientific practice of creating novel synthetic routes for complex molecules is called total synthesis . Strategies to design a synthesis include retrosynthesis , popularized by E.J. Corey , which starts with the target molecule and splices it to pieces according to known reactions. The pieces, or

4510-480: The early part of the 20th century, polymers and enzymes were shown to be large organic molecules, and petroleum was shown to be of biological origin. The multiple-step synthesis of complex organic compounds is called total synthesis. Total synthesis of complex natural compounds increased in complexity to glucose and terpineol . For example, cholesterol -related compounds have opened ways to synthesize complex human hormones and their modified derivatives. Since

4592-524: The environment through their extensive use as fuels and chemicals as well as through leaks or accidental spills during exploration, production, refining, or transport of fossil fuels. Anthropogenic hydrocarbon contamination of soil is a serious global issue due to contaminant persistence and the negative impact on human health. When soil is contaminated by hydrocarbons, it can have a significant impact on its microbiological, chemical, and physical properties. This can serve to prevent, slow down or even accelerate

4674-429: The first effective medicinal treatment of syphilis , and thereby initiated the medical practice of chemotherapy . Ehrlich popularized the concepts of "magic bullet" drugs and of systematically improving drug therapies. His laboratory made decisive contributions to developing antiserum for diphtheria and standardizing therapeutic serums. Early examples of organic reactions and applications were often found because of

4756-422: The fossilization of living beings, i.e., biomolecules. See also: peptide synthesis , oligonucleotide synthesis and carbohydrate synthesis . In pharmacology, an important group of organic compounds is small molecules , also referred to as 'small organic compounds'. In this context, a small molecule is a small organic compound that is biologically active but is not a polymer . In practice, small molecules have

4838-437: The functional group have an intermolecular and intramolecular effect on the surrounding environment and pH level. Different functional groups have different p K a values and bond strengths (single, double, triple) leading to increased electrophilicity with lower p K a and increased nucleophile strength with higher p K a . More basic/nucleophilic functional groups desire to attack an electrophilic functional group with

4920-495: The growth of vegetation depending on the exact changes that occur. Crude oil and natural gas are the two largest sources of hydrocarbon contamination of soil. Bioremediation of hydrocarbon from soil or water contaminated is a formidable challenge because of the chemical inertness that characterize hydrocarbons (hence they survived millions of years in the source rock). Nonetheless, many strategies have been devised, bioremediation being prominent. The basic problem with bioremediation

5002-494: The halogens are not normally grouped separately. Others are sometimes put into major groups within organic chemistry and discussed under titles such as organosulfur chemistry , organometallic chemistry , organophosphorus chemistry and organosilicon chemistry . Organic reactions are chemical reactions involving organic compounds . Many of these reactions are associated with functional groups. The general theory of these reactions involves careful analysis of such properties as

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5084-447: The lack of convention it was possible to have multiple names for the same compound. This led to the creation of the Geneva rules in 1892. The concept of functional groups is central in organic chemistry, both as a means to classify structures and for predicting properties. A functional group is a molecular module, and the reactivity of that functional group is assumed, within limits, to be

5166-710: The majority of known chemicals. The bonding patterns of carbon, with its valence of four—formal single, double, and triple bonds, plus structures with delocalized electrons —make the array of organic compounds structurally diverse, and their range of applications enormous. They form the basis of, or are constituents of, many commercial products including pharmaceuticals ; petrochemicals and agrichemicals , and products made from them including lubricants , solvents ; plastics ; fuels and explosives . The study of organic chemistry overlaps organometallic chemistry and biochemistry , but also with medicinal chemistry , polymer chemistry , and materials science . Organic chemistry

5248-562: The molecule more acidic or basic due to their electronic influence on surrounding parts of the molecule. As the p K a (aka basicity ) of the molecular addition/functional group increases, there is a corresponding dipole , when measured, increases in strength. A dipole directed towards the functional group (higher p K a therefore basic nature of group) points towards it and decreases in strength with increasing distance. Dipole distance (measured in Angstroms ) and steric hindrance towards

5330-412: The molecule of interest. This parent name is then modified by prefixes, suffixes, and numbers to unambiguously convey the structure. Given that millions of organic compounds are known, rigorous use of systematic names can be cumbersome. Thus, IUPAC recommendations are more closely followed for simple compounds, but not complex molecules. To use the systematic naming, one must know the structures and names of

5412-505: The multiple bonds to produce polyethylene , polybutylene , and polystyrene . The alkyne acetylene polymerizes to produce polyacetylene . Oligomers (chains of a few monomers) may be produced, for example in the Shell higher olefin process , where α-olefins are extended to make longer α-olefins by adding ethylene repeatedly. Some hydrocarbons undergo metathesis , in which substituents attached by C–C bonds are exchanged between molecules. For

5494-437: The organic dye now known as Perkin's mauve . His discovery, made widely known through its financial success, greatly increased interest in organic chemistry. A crucial breakthrough for organic chemistry was the concept of chemical structure, developed independently in 1858 by both Friedrich August Kekulé and Archibald Scott Couper . Both researchers suggested that tetravalent carbon atoms could link to each other to form

5576-464: The organic solute and with the organic solvent. Various specialized properties of molecular crystals and organic polymers with conjugated systems are of interest depending on applications, e.g. thermo-mechanical and electro-mechanical such as piezoelectricity , electrical conductivity (see conductive polymers and organic semiconductors ), and electro-optical (e.g. non-linear optics ) properties. For historical reasons, such properties are mainly

5658-422: The parent structures. Parent structures include unsubstituted hydrocarbons, heterocycles, and mono functionalized derivatives thereof. Nonsystematic nomenclature is simpler and unambiguous, at least to organic chemists. Nonsystematic names do not indicate the structure of the compound. They are common for complex molecules, which include most natural products. Thus, the informally named lysergic acid diethylamide

5740-769: The polarity of the molecules and their molecular weight. Some organic compounds, especially symmetrical ones, sublime . A well-known example of a sublimable organic compound is para-dichlorobenzene , the odiferous constituent of modern mothballs. Organic compounds are usually not very stable at temperatures above 300 °C, although some exceptions exist. Neutral organic compounds tend to be hydrophobic ; that is, they are less soluble in water than inorganic solvents. Exceptions include organic compounds that contain ionizable groups as well as low molecular weight alcohols , amines , and carboxylic acids where hydrogen bonding occurs. Otherwise, organic compounds tend to dissolve in organic solvents . Solubility varies widely with

5822-520: The polysaccharides), the nucleic acids (which include DNA and RNA as polymers), and the lipids . Besides, animal biochemistry contains many small molecule intermediates which assist in energy production through the Krebs cycle , and produces isoprene , the most common hydrocarbon in animals. Isoprenes in animals form the important steroid structural ( cholesterol ) and steroid hormone compounds; and in plants form terpenes , terpenoids , some alkaloids , and

5904-401: The reactions of alkenes and oxygen. This process is the basis of rancidification and paint drying . Benzene burns with sooty flame when heated in air: Saturated hydrocarbons react with chlorine and fluorine . In the case of chlorination, one of the chlorine atoms replaces a hydrogen atom. The reactions proceed via free-radical pathways , in which the halogen first dissociates into

5986-410: The room lacks enough oxygen to permit oxidation of the soot particles. Firefighters often look to see if there is soot on the inside of windows and in any cracks in the window (caused e.g. by the heat). The windows may also have a slight vibration due to varying pressure within the compartment due to intermittent combustion. If firefighters discover a room sucking air into itself, for example through

6068-589: The same in a variety of molecules. Functional groups can have a decisive influence on the chemical and physical properties of organic compounds. Molecules are classified based on their functional groups. Alcohols, for example, all have the subunit C-O-H. All alcohols tend to be somewhat hydrophilic , usually form esters , and usually can be converted to the corresponding halides . Most functional groups feature heteroatoms (atoms other than C and H). Organic compounds are classified according to functional groups, alcohols, carboxylic acids, amines, etc. Functional groups make

6150-737: The simple non-ring structured hydrocarbons have higher viscosities , lubricating indices, boiling points, and solidification temperatures. At the opposite extreme from methane lie the heavy tars that remain as the lowest fraction in a crude oil refining retort. They are collected and widely utilized as roofing compounds, pavement material ( bitumen ), wood preservatives (the creosote series) and as extremely high viscosity shear-resisting liquids. Some large-scale non-fuel applications of hydrocarbons begin with ethane and propane, which are obtained from petroleum and natural gas. These two gases are converted either to syngas or to ethylene and propylene respectively. Global consumption of benzene in 2021

6232-517: The source of virtually all synthetic organic compounds, including plastics and pharmaceuticals. Natural gas is consumed almost exclusively as fuel. Coal is used as a fuel and as a reducing agent in metallurgy . A small fraction of hydrocarbon found on earth, and all currently known hydrocarbon found on other planets and moons, is thought to be abiological . Hydrocarbons such as ethylene, isoprene, and monoterpenes are emitted by living vegetation. Some hydrocarbons also are widespread and abundant in

6314-430: The start of the 20th century, complexity of total syntheses has been increased to include molecules of high complexity such as lysergic acid and vitamin B 12 . The discovery of petroleum and the development of the petrochemical industry spurred the development of organic chemistry. Converting individual petroleum compounds into types of compounds by various chemical processes led to organic reactions enabling

6396-415: The subjects of the areas of polymer science and materials science . The names of organic compounds are either systematic, following logically from a set of rules, or nonsystematic, following various traditions. Systematic nomenclature is stipulated by specifications from IUPAC (International Union of Pure and Applied Chemistry). Systematic nomenclature starts with the name for a parent structure within

6478-448: The surrounding air. ISO 13943 broadly defines flashover as a "transition to a state of total surface involvement in a fire of combustible materials within an enclosure." This definition embraces several different scenarios and includes backdrafts, but there is considerable disagreement about categorizing backdrafts as flashovers. In common usage, the term flashover describes the near-simultaneous ignition of material caused by heat attaining

6560-509: Was cautious about claiming he had disproved vitalism, this was the first time a substance thought to be organic was synthesized in the laboratory without biological (organic) starting materials. The event is now generally accepted as indeed disproving the doctrine of vitalism. After Wöhler, Justus von Liebig worked on the organization of organic chemistry, being considered one of its principal founders. In 1856, William Henry Perkin , while trying to manufacture quinine , accidentally produced

6642-403: Was endowed with a "vital force". During the first half of the nineteenth century, some of the first systematic studies of organic compounds were reported. Around 1816 Michel Chevreul started a study of soaps made from various fats and alkalis . He separated the acids that, in combination with the alkali, produced the soap. Since these were all individual compounds, he demonstrated that it

6724-467: Was possible to make a chemical change in various fats (which traditionally come from organic sources), producing new compounds, without "vital force". In 1828 Friedrich Wöhler produced the organic chemical urea (carbamide), a constituent of urine , from inorganic starting materials (the salts potassium cyanate and ammonium sulfate ), in what is now called the Wöhler synthesis . Although Wöhler himself

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