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Peroxide Group V
In chemistry, peroxides are a group of compounds with the structure , where the R's represent a radical (a portion of a complete molecule; not necessarily a free radical) and O's are single oxygen atoms. Oxygen atoms are joined to each other and to adjacent elements through single covalent bonds, denoted by dashes or lines. The group in a peroxide is often called the peroxide group, though some nomenclature discrepancies exist. This linkage is recognized as a common polyatomic ion, and exists in many molecules. General structure The characteristic structure of any regular peroxide is the oxygen–oxygen covalent single bond, which connects the two main atoms together. In the event that the molecule has no chemical substituents, the peroxide group will have a ��2 net charge. Each oxygen atom has a charge of negative one, as 5 of its valence electrons remain in the outermost orbital shell whilst one is occupied in the covalent bond. Because of the nature of the covalent bon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemistry
Chemistry is the scientific study of the properties and behavior of matter. It is a physical science within the natural sciences that studies the chemical elements that make up matter and chemical compound, compounds made of atoms, molecules and ions: their composition, structure, properties, behavior and the changes they undergo during chemical reaction, reactions with other chemical substance, substances. Chemistry also addresses the nature of chemical bonds in chemical compounds. In the scope of its subject, chemistry occupies an intermediate position between physics and biology. It is sometimes called the central science because it provides a foundation for understanding both Basic research, basic and Applied science, applied scientific disciplines at a fundamental level. For example, chemistry explains aspects of plant growth (botany), the formation of igneous rocks (geology), how atmospheric ozone is formed and how environmental pollutants are degraded (ecology), the prop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peroxy Acid
A peroxy acid (often spelled as one word, peroxyacid, and sometimes called peracid) is an acid which contains an acidic group. The two main classes are those derived from conventional mineral acids, especially sulfuric acid, and the peroxy derivatives of organic carboxylic acids. They are generally strong oxidizers. Inorganic peroxy acids Peroxymonosulfuric acid (Caro's acid) is probably the most important inorganic peracid, at least in terms of its production scale. It is used for the bleaching of pulp and for the detoxification of cyanide in the mining industry. It is produced by treating sulfuric acid with hydrogen peroxide. Peroxymonophosphoric acid () is prepared similarly. Some peroxy acids are only hypothetical, but their anions are known. This is the case for peroxycarbonate and perborate (see sodium perborate). Organic peracids Production Several organic peroxyacids are commercially useful. They can be prepared in several ways. Most commonly, peracids are ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tert-Butyl Hydroperoxide
''tert''-Butyl hydroperoxide (tBuOOH) is the organic compound with the formula (CH3)3COOH. It is one of the most widely used hydroperoxides in a variety of oxidation processes, like the Halcon process. It is normally supplied as a 69–70% aqueous solution. Compared to hydrogen peroxide and organic peracids, ''tert''-butyl hydroperoxide is less reactive and more soluble in organic solvents. Overall, it is renowned for the convenient handling properties of its solutions. Its solutions in organic solvents are highly stable. Application Industrially, ''tert''-butyl hydroperoxide is used to prepare propylene oxide. In the Halcon process, molybdenum-based catalysts are used for this reaction: :(CH3)3COOH + CH2=CHCH3 → (CH3)3COH + CH2OCHCH3 The byproduct t-butanol can be dehydrated to isobutene and converted to MTBE. On a much smaller scale, ''tert''-butyl hydroperoxide is used to produce some fine chemicals by the Sharpless epoxidation. Synthesis and production Many synt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Peroxide
In organic chemistry, organic peroxides are organic compounds containing the peroxide functional group (). If the R′ is hydrogen, the compounds are called hydroperoxides, which are discussed in that article. The O−O bond of peroxides easily breaks, producing free radicals of the form (the dot represents an unpaired electron). Thus, organic peroxides are useful as radical initiator, initiators for some types of polymerization, such as the Acrylic resin, acrylic, unsaturated polyester, and vinyl ester resins used in glass-reinforced plastics. methyl ethyl ketone peroxide, MEKP and benzoyl peroxide are commonly used for this purpose. However, the same property also means that organic peroxides can explosively combust. Organic peroxides, like their inorganic counterparts, are often powerful bleaching agents. Types of organic peroxides Organic peroxides are classified (i) by the presence or absence of a hydroxyl () terminus and (ii) by the presence of alkyl vs acyl substituents. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc Peroxide
Zinc peroxide (ZnO2) is a chemical compound of zinc that appears as a bright yellow powder at room temperature. It was historically used as a surgical antiseptic. More recently zinc peroxide has also been used as an oxidant in explosives and pyrotechnic mixtures. Its properties have been described as a transition between ionic and covalent peroxides. Preparation and structure Structure of solid zinc peroxide, left, 120px, thumb Zinc peroxide can be synthesized through the reaction of zinc chloride and hydrogen peroxide. According to X-ray crystallography, the compound consists of octahedral Zn(II) centers bonded to six distinct peroxide (O22-) ligands. The overall motif is very similar to that for iron pyrite (FeS2). The structure, with intact O-O bonds, makes clear that this material is a peroxide, not a dioxide. Medical Use The treatment of burrowing ulcers in the abdominal wall with zinc peroxide was first recorded in 1933 and throughout the 1940s ZnO2 was used as a disinfec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Peroxide
Sodium peroxide is an inorganic compound with the formula Na2 O2. This yellowish solid is the product of sodium ignited in excess oxygen. It is a strong base. This metal peroxide exists in several hydrates and peroxyhydrates including Na2O2·2H2O2·4H2O, Na2O2·2H2O, Na2O2·2H2O2, and Na2O2·8H2O.Harald Jakob, Stefan Leininger, Thomas Lehmann, Sylvia Jacobi, Sven Gutewort. "Peroxo Compounds, Inorganic". ''Ullmann's Encyclopedia of Industrial Chemistry'', 2007, Wiley-VCH, Weinheim. . The octahydrate, which is simple to prepare, is white, in contrast to the anhydrous material. Properties Sodium peroxide crystallizes with hexagonal symmetry. Upon heating, the hexagonal form undergoes a transition into a phase of unknown symmetry at 512 °C. With further heating above the 657 °C boiling point, the compound decomposes to Na2O, releasing O2.Lewis, R. J. ''Sax's Dangerous Properties of Industrial Materials, 10th ed.'', John Wiley & Sons, Inc.: 2000. : 2 Na2O2 → 2 Na2O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barium Peroxide
Barium peroxide is an inorganic compound with the formula . This white solid (gray when impure) is one of the most common inorganic peroxides, and it was the first peroxide compound discovered. Being an oxidizer and giving a vivid green colour upon ignition (as do all barium compounds), it finds some use in fireworks; historically, it was also used as a precursor for hydrogen peroxide. Structure Barium peroxide consists of barium cations and peroxide anions . The solid is isomorphous to calcium carbide, . Preparation and use Barium peroxide arises by the reversible reaction of with barium oxide. The peroxide forms around 500 °C and oxygen is released above 820 °C. : This reaction is the basis for the now-obsolete Brin process for separating oxygen from the atmosphere. Other oxides, e.g. and SrO, behave similarly.Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. . In another obsolete application, barium peroxide was once used to produce hy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metal Peroxide
A metal () is a material that, when polished or fractured, shows a lustrous appearance, and conducts electrical resistivity and conductivity, electricity and thermal conductivity, heat relatively well. These properties are all associated with having electrons available at the Fermi level, as against nonmetallic materials which do not. Metals are typically ductile (can be drawn into a wire) and malleable (can be shaped via hammering or pressing). A metal may be a chemical element such as iron; an alloy such as stainless steel; or a molecular compound such as polythiazyl, polymeric sulfur nitride. The general science of metals is called metallurgy, a subtopic of materials science; aspects of the electronic and thermal properties are also within the scope of condensed matter physics and solid-state chemistry, it is a multidisciplinary topic. In colloquial use materials such as steel alloys are referred to as metals, while others such as polymers, wood or ceramics are nonmetallic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Main Group Element
In chemistry and atomic physics, the main group is the group (periodic table), group of chemical element, elements (sometimes called the representative elements) whose lightest members are represented by helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, and fluorine as arranged in the periodic table of the elements. The main group includes the elements (except hydrogen, which is sometimes not included) in groups 1 and 2 (s-block), and groups 13 to 18 (p-block). The s-block elements are primarily characterised by one main oxidation state, and the p-block elements, when they have multiple oxidation states, often have common oxidation states separated by two units. Main-group elements (with some of the lighter transition metals) are the most abundance of the chemical elements, abundant elements on Earth, in the Solar System, and in the universe. Group 12 elements are often considered to be transition metals; however, zinc (Zn), cadmium (Cd), and mercury (element), mercury ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Main Group Peroxides
Main may refer to: Geography *Main River (other), multiple rivers with the same name *Ma'in, an ancient kingdom in modern-day Yemen * Main, Iran, a village in Fars Province *Spanish Main, the Caribbean coasts of mainland Spanish territories in the 16th and 17th centuries *'' The Main'', the diverse core running through Montreal, Quebec, Canada, also separating the Two Solitudes * Main (lunar crater), located near the north pole of the Moon * Main (Martian crater) People and organizations * Main (surname), a list of people with this family name *Main, alternate spelling for the Minaeans, an ancient people of modern-day Yemen * Main (band), a British ambient band formed in 1991 * Chas. T. Main, an American engineering and hydroelectric company founded in 1893 *MAIN (Mountain Area Information Network), former operator of WPVM-LP (MAIN-FM) in Asheville, North Carolina, U.S. * Main Deli Steak House ("The Main"), a smoked-meat delicatessen in Montreal, Quebec, Canada Ships ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Peroxydisulfate
Potassium persulfate is the inorganic compound with the formula K2 S2O8. Also known as potassium peroxydisulfate, it is a white solid that is sparingly soluble in cold water, but dissolves better in warm water. This salt is a powerful oxidant, commonly used to initiate polymerizations. Structure The sodium and potassium salts are very similar. In the potassium salt, the O-O distance is 1.495Å. The individual sulfate groups are tetrahedral, with three short S-O distances near 1.43 and one long S-O bond at 1.65Å. Preparation Potassium persulfate can be prepared by electrolysis of a cold solution potassium bisulfate in sulfuric acid at a high current density. : 2 KHSO4 → K2S2O8 + H2 It can also be prepared by adding potassium bisulfate (KHSO4) to a solution of the more soluble salt ammonium peroxydisulfate (NH4)2S2O8. In principle it can be prepared by chemical oxidation of potassium sulfate using fluorine. Several million kilograms of the ammonium, sodium, and potassium s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peracetic Acid
Peracetic acid (also known as peroxyacetic acid, or Percidine) is an organic compound with the formula CH3CO3H. This peroxy acid is a colorless liquid with a characteristic acrid odor reminiscent of acetic acid. It can be highly corrosive. Peracetic acid is a weaker acid than the parent acetic acid, with a p''K''a of 8.2. Production Peracetic acid is produced industrially by the autoxidation of acetaldehyde: :O2 + CH3CHO → CH3CO3H Peracetic acid is conventionally prepared by combining acetic acid and hydrogen peroxide with homogeneous acid catalysts (e.g., sulfuric acid), which facilitate the reaction and achieve equilibrium between the reagents and product: :H2O2 + CH3CO2H CH3CO3H + H2O While it is feasible to create peracetic acid by combining consumer-grade vinegar (5% acetic acid) and hydrogen peroxide (3%) without an acid catalyst, the low concentration of reagents will result in a slow reaction rate at room temperature. Extrapolating from published reaction rates, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
