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Methylene Glycol
Methanediol, also known as formaldehyde monohydrate or methylene glycol, is an organic compound with chemical formula . It is the simplest geminal diol, and the simplest sugar alcohol. In aqueous solutions it coexists with oligomers (short polymers). The compound is closely related and convertible to the industrially significant derivatives paraformaldehyde (), formaldehyde (), and 1,3,5-trioxane (). Methanediol is a product of the Hydration reaction, hydration of formaldehyde. The equilibrium constant for hydration is estimated to be 103, Eric V. Anslyn, Dennis A. Dougherty (2006)''Modern physical organic chemistry'' University Science Books. . 1095 pages predominates in dilute (<0.1%) solution. In more concentrated solutions, it oligomerizes to . Occurrence The dianion, methanediolate, is believed to be an intermediate in the crossed Cannizzaro reaction. Gaseous methanediols can be generated by electron irradiation and sublimation of ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, hydrogen cyanide), are not classified as organic compounds and are considered inorganic. Other than those just named, little consensus exists among chemists on precisely which carbon-containing compounds are excluded, making any rigorous definition of an organic compound elusive. Although organic compounds make up only a small percentage of Earth's crust, they are of central importance because all known life is based on organic compounds. Living t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. Oxygen is Earth's most abundant element, and after hydrogen and helium, it is the third-most abundant element in the universe. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a colorless and odorless diatomic gas with the formula . Diatomic oxygen gas currently constitutes 20.95% of the Earth's atmosphere, though this has changed considerably over long periods of time. Oxygen makes up almost half of the Earth's crust in the form of oxides.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. Many major classes of organic molecules in living organisms contain oxygen atoms, such as proteins, nucleic acids, carbohydrates, and fats, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbohydrates
In organic chemistry, a carbohydrate () is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water) and thus with the empirical formula (where ''m'' may or may not be different from ''n''), which does not mean the H has covalent bonds with O (for example with , H has a covalent bond with C but not with O). However, not all carbohydrates conform to this precise stoichiometric definition (e.g., uronic acids, deoxy-sugars such as fucose), nor are all chemicals that do conform to this definition automatically classified as carbohydrates (e.g. formaldehyde and acetic acid). The term is most common in biochemistry, where it is a synonym of saccharide (), a group that includes sugars, starch, and cellulose. The saccharides are divided into four chemical groups: monosaccharides, disaccharides, oligosaccharides, and polysaccharides. Monosaccharides and disaccharides, the smallest (lower molecular weight) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrates
In chemistry, a hydrate is a substance that contains water Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a ... or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labeled before their chemical structure was understood. Chemical nature Inorganic chemistry Hydrates are inorganic salts "containing water molecules combined in a definite ratio as an integral part of the crystal" that are either bound to a metal center or that have crystallized with the metal complex. Such hydrates are also said to contain ''water of crystallization'' or ''water of hydration''. If the water is heavy water in which the constituent hydrogen is the isotope deuterium, then the term ''deuterate'' may be used in place of ''hy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthocarbonic Acid
Orthocarbonic acid (methanetetrol) is the name given to a hypothetical compound with the chemical formula or . Its molecular structure consists of a single carbon atom bonded to four hydroxy groups. It would be therefore a fourfold alcohol. In theory it could lose four protons to give the hypothetical oxocarbon anion (orthocarbonate), and is therefore considered an oxoacid of carbon. The compound has also been given the nickname of "Hitler's Acid" due to the Ball-and-stick model of the compound resembling the Swastika symbol. Orthocarbonic acid is highly unstable. Calculations show that it decomposes spontaneously into carbonic acid and water: : H4CO4 -> H2CO3 + H2O Orthocarbonic acid is one of the group of ''ortho acids'' that have the general structure of .The term ''ortho acid'' is also used to refer to the most hydroxylated acid in a set of oxoacids. Researchers predict that orthocarbonic acid is stable at high pressure; hence it may form in the interior of the ice gia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthoformic Acid
Orthoformic acid or methanetriol is a hypothetical chemical compound with the formula . In this molecule, the central carbon atom is bound to one hydrogen and three hydroxyl groups. Orthoformic acid has not been isolated to date, and is believed to be unstable, decomposing into water and formic acid.Böhm, S., Antipova, D. and Kuthan, J. (1996), "Study of methanetriol decomposition mechanisms". ''International Journal of Quantum Chemistry'', volume 60, pages 649–655. Esters Methanetriol esters, known as orthoformates, are well known and commercially available.Peter P. T. Sah, Tsu Sheng Ma (1932), ""ESTERS OF ORTHOFORMIC ACID". ''J. Am. Chem. Soc.'', volume 54, issue 7, pages 2964–2966 H. W. Post (1943), "The Chemistry of the Aliphatic Orthoesters", Reinhold, 188 pages Like acetals, they are stable towards bases but easily hydrolyzed in acidic conditions to the alcohol and an ester of formic acid. They are used as mild dehydrating agents. Especially well known are trimethyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regulatory Toxicology And Pharmacology
''Regulatory Toxicology and Pharmacology'' is a monthly peer-reviewed scientific journal which covers legal aspects of toxicological and pharmacological regulations. It is published by Elsevier on behalf of the International Society of Regulatory Toxicology & Pharmacology. The current co-editors-in-chief are Lesa L. Aylward and Martin van den Berg. Conflicts of interest In 2002, a group of 45 academics wrote a letter accusing the journal of a concealed pro-industry bias, a possible lack of full and independent peer review, and a failure to disclose conflicts of interest, citing a case in which Gio Batta Gori, then-current editor-in-chief, was paid $30,000 by the Tobacco Institute to write an article later published in the journal dismissing the health risks of secondhand smoke. The letter's coordinator later commented that the journal "reads like an industry trade publication, but it's masked as a peer-reviewed journal" and that it lacked any "credible peer-review process." In r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territories, nine Minor Outlying Islands, and 326 Indian reservations. The United States is also in free association with three Pacific Island sovereign states: the Federated States of Micronesia, the Marshall Islands, and the Republic of Palau. It is the world's third-largest country by both land and total area. It shares land borders with Canada to its north and with Mexico to its south and has maritime borders with the Bahamas, Cuba, Russia, and other nations. With a population of over 333 million, it is the most populous country in the Americas and the third most populous in the world. The national capital of the United States is Washington, D.C. and its most populous city and principal financial center is New York City. Paleo-Americ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brazilian Hair Straightening
Brazilian hair straightening is a semi-permanent hair smoothing method done by temporarily sealing a liquid keratin and a preservative solution into the hair with a hair iron. The technique has many variations and is known by several other names and brands, including Brazilian Blowout, Breezilian straightening, Brazilian Keratin Treatment, BKT, and Keratin Cure. It is called Escova Progressiva in Brazil and Alisado brasileiro in Portugal. The original formulation included formaldehyde or methylene glycol . The two products readily interconvert, and coexist in chemical equilibrium, when dissolved in water or body fluids. Since formaldehyde is a known health hazard, the compositions have been banned in several countries including Canada and the European Union. It is still performed in the United States, though there are regulations and have been controversies regarding the treatment. Characteristics Brazilian hair straightening treatments are meant to mostly or partially eli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ozonolysis
In organic chemistry, ozonolysis is an organic reaction where the unsaturated bonds of alkenes (), alkynes (), or azo compounds () are cleaved with ozone (). Alkenes and alkynes form organic compounds in which the multiple carbon–carbon bond has been replaced by a carbonyl () group while azo compounds form nitrosamines (). The outcome of the reaction depends on the type of multiple bond being oxidized and the work-up conditions. Ozonolysis of alkenes Alkenes can be oxidized with ozone to form alcohols, aldehydes or ketones, or carboxylic acids. In a typical procedure, ozone is bubbled through a solution of the alkene in methanol at −78 °C until the solution takes on a characteristic blue color, which is due to unreacted ozone. This indicates complete consumption of the alkene. Alternatively, various other chemicals can be used as indicators of this endpoint by detecting the presence of ozone. If ozonolysis is performed by bubbling a stream of ozone-enriched oxygen t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonyl
In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double-bonded to an oxygen atom: C=O. It is common to several classes of organic compounds, as part of many larger functional groups. A compound containing a carbonyl group is often referred to as a carbonyl compound. The term carbonyl can also refer to carbon monoxide as a ligand in an inorganic or organometallic complex (a metal carbonyl, e.g. nickel carbonyl). The remainder of this article concerns itself with the organic chemistry definition of carbonyl, where carbon and oxygen share a double bond. Carbonyl compounds In organic chemistry, a carbonyl group characterizes the following types of compounds: Other organic carbonyls are urea and the carbamates, the derivatives of acyl chlorides chloroformates and phosgene, carbonate esters, thioesters, lactones, lactams, hydroxamates, and isocyanates. Examples of inorganic carbonyl compounds are carbon dioxide and carbonyl sulfide. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanol
Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical and the simplest aliphatic alcohol, with the formula C H3 O H (a methyl group linked to a hydroxyl group, often abbreviated as MeOH). It is a light, volatile, colourless, flammable liquid with a distinctive alcoholic odour similar to that of ethanol (potable alcohol). A polar solvent, methanol acquired the name wood alcohol because it was once produced chiefly by the destructive distillation of wood. Today, methanol is mainly produced industrially by hydrogenation of carbon monoxide. Methanol consists of a methyl group linked to a polar hydroxyl group. With more than 20 million tons produced annually, it is used as a precursor to other commodity chemicals, including formaldehyde, acetic acid, methyl tert-butyl ether, methyl benzoate, anisole, peroxyacids, as well as a host of more specialised chemicals. Occurrence Small amounts of methanol are present in normal, healthy hu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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