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Boron Oxide
Boron oxide may refer to one of several oxides of boron: *Boron trioxide (B2O3, diboron trioxide), the most common form *Boron monoxide (B2O), theoretical, unstable *Boron suboxide Boron suboxide (chemical formula B6O) is a solid compound with a structure built of eight icosahedra at the apexes of the rhombohedral unit cell. Each icosahedron is composed of twelve boron atoms. Two oxygen atoms are located in the interstices al ... (B6O) Boron compounds {{Chemistry index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxide
An oxide () is a chemical compound that contains at least one oxygen atom and one other element in its chemical formula. "Oxide" itself is the dianion of oxygen, an O2– (molecular) ion. with oxygen in the oxidation state of −2. Most of the Earth's crust consists of oxides. Even materials considered pure elements often develop an oxide coating. For example, aluminium foil develops a thin skin of Al2O3 (called a passivation layer) that protects the foil from further corrosion.Greenwood, N. N.; & Earnshaw, A. (1997). Chemistry of the Elements (2nd Edn.), Oxford:Butterworth-Heinemann. . Stoichiometry (the measurable relationship between reactants and chemical equations of a equation or reaction) Oxides are extraordinarily diverse in terms of stoichiometries and in terms of the structures of each stoichiometry. Most elements form oxides of more than one stoichiometry. A well known example is carbon monoxide and carbon dioxide.Greenwood, N. N.; & Earnshaw, A. (1997). Chemistry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boron
Boron is a chemical element with the symbol B and atomic number 5. In its crystalline form it is a brittle, dark, lustrous metalloid; in its amorphous form it is a brown powder. As the lightest element of the ''boron group'' it has three valence electrons for forming covalent bonds, resulting in many compounds such as boric acid, the mineral borax, sodium borate, and the ultra-hard crystals of boron carbide and boron nitride. Boron is synthesized entirely by cosmic ray spallation and supernovae and not by stellar nucleosynthesis, so it is a low-abundance element in the Solar System and in the Crust (geology), Earth's crust. It constitutes about 0.001 percent by weight of Earth's crust. It is concentrated on Earth by the water-solubility of its more common naturally occurring compounds, the borate minerals. These are mined industrially as evaporites, such as borax and kernite. The largest known deposits are in Turkey, the largest producer of boron minerals. Elemental b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boron Trioxide
Boron trioxide or diboron trioxide is the oxide of boron with the formula . It is a colorless transparent solid, almost always glassy (amorphous), which can be crystallized only with great difficulty. It is also called boric oxide or boria. It has many important industrial applications, chiefly in ceramics as a flux for glazes and enamels and in the production of glasses. Structure Boron trioxide has three known forms, one amorphous and two crystalline. Amorphous form The amorphous form (g-) is by far the most common. It is thought to be composed of boroxol rings which are six-membered rings composed of alternating 3-coordinate boron and 2-coordinate oxygen. Because of the difficulty of building disordered models at the correct density with many boroxol rings, this view was initially controversial, but such models have recently been constructed and exhibit properties in excellent agreement with experiment. It is now recognized, from experimental and theoretical studies, that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boron Monoxide
Boron monoxide (B2O) is a chemical compound of boron and oxygen. Two experimental studies have proposed existence of diamond-like and graphite-like B2O, as for boron nitride and carbon solids. However, a later, systematic, experimental study of boron oxide phase diagram suggests that B2O is unstable. The instability of the graphite-like B2O phase was also predicted theoretically. See also * Boron suboxide * Boron trioxide * Boron * Aluminium(I) oxide Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It ha ... References Boron compounds Oxides {{material-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boron Suboxide
Boron suboxide (chemical formula B6O) is a solid compound with a structure built of eight icosahedra at the apexes of the rhombohedral unit cell. Each icosahedron is composed of twelve boron atoms. Two oxygen atoms are located in the interstices along the 11rhombohedral direction. Due to its short interatomic bond lengths and strongly covalent character, B6O displays a range of outstanding physical and chemical properties such as great hardness (close to that of rhenium diboride and boron nitride), low mass density, high thermal conductivity, high chemical inertness, and excellent wear resistance. and references therein B6O can be synthesized by reducing B2O3 with boron or by oxidation of boron with zinc oxide or other oxidants. These boron suboxide materials formed at or near ambient pressure are generally oxygen deficient and non-stoichiometric (B6Ox, x<0.9) and have poor crystallinity and very small grain size (less than 5 μm). High pressure applied during the synthesis o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
