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Cobalt Carbonate
Cobalt(II) carbonate is the inorganic compound with the formula CoCO3. This reddish paramagnetic solid is an intermediate in the hydrometallurgical purification of cobalt from its ores. It is an inorganic pigment, and a precursor to catalysts. Cobalt(II) carbonate also occurs as the rare red/pink mineral spherocobaltite. Preparation and structure It is prepared by combining solutions cobaltous sulfate and sodium bicarbonate: :CoSO4 + 2 NaHCO3 → CoCO3 + Na2SO4 + H2O + CO2 This reaction is used in the precipitation of cobalt from an extract of its roasted ores. CoCO3 adopts a structure like calcite, consisting of cobalt in an octahedral coordination geometry. Reactions Like most transition metal carbonates, cobalt carbonate is insoluble in water, but is readily attacked by mineral acids: :CoCO3 + 2 HCl + 5 H2O → o(H2O)6l2 + CO2 It is used to prepare many coordination complexes. The reaction of cobalt(II) carbonate and acetylacetone in the presence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cobalt(II) Oxide
Cobalt(II) oxide is an inorganic compound that has been described as an olive-green or gray solid. It is used extensively in the ceramics industry as an additive to create blue colored glazes and enamels as well as in the chemical industry for producing cobalt(II) salts. A related material is cobalt(II,III) oxide, a black solid with the formula Co3O4. Structure and properties CoO crystals adopt the periclase ( rock salt) structure with a lattice constant of 4.2615 Å. It is antiferromagnetic below 16 °C. Preparation Cobalt(II) oxide is prepared by oxidation of cobalt powder with air or by thermal decomposition of cobalt(II) nitrate or the carbonate. Cobalt(II,III) oxide decomposes to cobalt(II) oxide at 950 °C: :2 Co3O4 → 6 CoO + O2 It may also be prepared by precipitating the hydroxide, followed by thermal dehydration: : CoX2 + 2 KOH → Co(OH)2 + 2 KX : Co(OH)2 → CoO + H2O Reactions As can be expected, cobalt(II) oxide reacts with mineral acids to for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tris(acetylacetonato)cobalt(III)
Tris(acetylacetonato)cobalt(III) is the coordination complex with the formula Co(C5H7O2)3. Often abbreviated Co(acac)3, it is a green, diamagnetic solid that is soluble in organic solvents, but not in water. Owing to its solubility in organic solvents, tris(acetylacetonato)cobalt(III) is used to produce homogeneous catalysts by reduction. Structure The structure of the complex has been confirmed by X-ray crystallography. The three acac ligands bind in a bidentate fashion to cobalt, defining an octahedral complex. The solid is isomorphous with tris(acetylacetonato)iron(III), tris(acetylacetonato)manganese(III), and tris(acetylacetonato)aluminium. With D3-symmetry, these complexes are chiral and often can be resolved into the individual enantiomers. Synthesis and reactions Tris(acetylacetonato)cobalt(III) is prepared by the reaction of cobalt(II) carbonate and acetylacetone in the presence of hydrogen peroxide. One distinctive aspect of Co(acac)3 is its susceptibility toward elec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitamin B12
Vitamin B12, also known as cobalamin, is a water-soluble vitamin involved in metabolism. It is one of eight B vitamins. It is required by animals, which use it as a cofactor in DNA synthesis, in both fatty acid and amino acid metabolism. It is important in the normal functioning of the nervous system via its role in the synthesis of myelin, and in the circulatory system in the maturation of red blood cells in the bone marrow. Plants do not need cobalamin and carry out the reactions with enzymes that are not dependent on it. Vitamin B12 is the most chemically complex of all vitamins, and for humans, the only vitamin that must be sourced from animal-derived foods or from supplements. Only some archaea and bacteria can synthesize vitamin B12. Most people in developed countries get enough B12 from the consumption of meat or foods with animal sources. Foods containing vitamin B12 include meat, clams, liver, fish, poultry, eggs, and dairy products. Many breakfast cereals a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal Habit
In mineralogy, crystal habit is the characteristic external shape of an individual crystal or crystal group. The habit of a crystal is dependent on its crystallographic form and growth conditions, which generally creates irregularities due to limited space in the crystallizing medium (commonly in rocks).Klein, Cornelis, 2007, ''Minerals and Rocks: Exercises in Crystal and Mineral Chemistry, Crystallography, X-ray Powder Diffraction, Mineral and Rock Identification, and Ore Mineralogy,'' Wiley, third edition, Wenk, Hans-Rudolph and Andrei Bulakh, 2004, ''Minerals: Their Constitution and Origin,'' Cambridge, first edition, Recognizing the habit can aid in mineral identification and description, as the crystal habit is an external representation of the internal ordered atomic arrangement. Most natural crystals, however, do not display ideal habits and are commonly malformed. Hence, it is also important to describe the quality of the shape of a mineral specimen: * Euhedral: a c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Republic Of Congo
The Republic of the Congo (french: République du Congo, ln, Republíki ya Kongó), also known as Congo-Brazzaville, the Congo Republic or simply either Congo or the Congo, is a country located in the western coast of Central Africa to the west of the Congo river. It is bordered to the west by Gabon, to its northwest by Cameroon and its northeast by the Central African Republic, to the southeast by the Democratic Republic of the Congo, to its south by the Angolan exclave of Cabinda and to its southwest by the Atlantic Ocean. The region was dominated by Bantu-speaking tribes at least 3,000 years ago, who built trade links leading into the Congo River basin. Congo was formerly part of the French colony of Equatorial Africa. The Republic of the Congo was established on 28 November 1958 and gained independence from France in 1960. It was a Marxist–Leninist state from 1969 to 1992, under the name People's Republic of the Congo. The country has had multi-party elections sin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delftware
Delftware or Delft pottery, also known as Delft Blue ( nl, Delfts blauw) or as delf, is a general term now used for Dutch tin-glazed earthenware, a form of faience. Most of it is blue and white pottery, and the city of Delft in the Netherlands was the major centre of production, but the term covers wares with other colours, and made elsewhere. It is also used for similar pottery, English delftware. Delftware is one of the types of tin-glazed earthenware or faience in which a white glaze is applied, usually decorated with metal oxides, in particular the cobalt oxide that gives the usual blue, and can withstand high firing temperatures, allowing it to be applied under the glaze. Delftware forms part of the worldwide family of blue and white pottery, using variations of the plant-based decoration first developed in 14th-century Chinese porcelain, and in great demand in Europe. Delftware includes pottery objects of all descriptions - such as plates, vases, figurines and other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Essential Element
In the context of nutrition, a mineral is a chemical element required as an essential nutrient by organisms to perform functions necessary for life. However, the four major structural elements in the human body by weight (oxygen, hydrogen, carbon, and nitrogen), are usually not included in lists of major nutrient minerals (nitrogen is considered a "mineral" for plants, as it often is included in fertilizers). These four elements compose about 96% of the weight of the human body, and major minerals (macrominerals) and minor minerals (also called trace elements) compose the remainder. Nutrient minerals, being elements, cannot be synthesized biochemically by living organisms. Plants get minerals from soil. Most of the minerals in a human diet come from eating plants and animals or from drinking water. As a group, ''minerals'' are one of the four groups of essential nutrients, the others of which are vitamins, essential fatty acids, and essential amino acids. The five major minerals i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dietary Supplement
A dietary supplement is a manufactured product intended to supplement one's diet by taking a pill, capsule, tablet, powder, or liquid. A supplement can provide nutrients either extracted from food sources or that are synthetic in order to increase the quantity of their consumption. The class of nutrient compounds includes vitamins, minerals, fiber, fatty acids, and amino acids. Dietary supplements can also contain substances that have not been confirmed as being essential to life, but are marketed as having a beneficial biological effect, such as plant pigments or polyphenols. Animals can also be a source of supplement ingredients, such as collagen from chickens or fish for example. These are also sold individually and in combination, and may be combined with nutrient ingredients. The European Commission has also established harmonized rules to help insure that food supplements are safe and appropriately labeled. Creating an industry estimated to have a 2020 value of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cobalt Carbonyl
Dicobalt octacarbonyl is an organocobalt compound with composition . This metal carbonyl is used as a reagent and catalyst in organometallic chemistry and organic synthesis, and is central to much known organocobalt chemistry. It is the parent member of a family of hydroformylation catalysts. Each molecule consists of two cobalt atoms bound to eight carbon monoxide ligands, although multiple structural isomers are known. Some of the carbonyl ligands are labile. Synthesis, structure, properties Dicobalt octacarbonyl an orange-colored, pyrophoric solid. It is synthesised by the high pressure carbonylation of cobalt(II) salts: : The preparation is often carried out in the presence of cyanide, converting the cobalt(II) salt into a hexacyanocobaltate(II) complex that reacts with carbon monoxide to yield . Acidification produces cobalt tetracarbonyl hydride, , which degrades near room temperature to dicobalt octacarbonyl and hydrogen. It can also be prepared by heating cobalt metal to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cobalt(II,III) Oxide
Cobalt(II,III) oxide is an inorganic compound with the formula Co3O4. It is one of two well characterized cobalt oxides. It is a black antiferromagnetic solid. As a mixed valence compound, its formula is sometimes written as CoIICoIII2O4 and sometimes as CoO•Co2O3. Structure Co3O4 adopts the normal spinel structure, with Co2+ ions in tetrahedral interstices and Co3+ ions in the octahedral interstices of the cubic close-packed lattice of oxide anions. Synthesis Cobalt(II) oxide, CoO, converts to Co3O4 upon heating at around 600–700 °C in air. Above 900 °C, CoO is stable. These reaction are described by the following equilibrium: :2 Co3O4 6 CoO + O2 Applications Cobalt(II,III) oxide is used as a blue coloring agent for pottery enamel and glass, as an alternative to cobalt(II) oxide.Frank Hamer, Janet Hamer (2004)''The Potter's Dictionary of Materials and Techniques'' University of Pennsylvania Press; 437 pp. Cobalt(II,III) oxide is used as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcining
Calcination refers to thermal treatment of a solid chemical compound (e.g. mixed carbonate ores) whereby the compound is raised to high temperature without melting under restricted supply of ambient oxygen (i.e. gaseous O2 fraction of air), generally for the purpose of removing impurities or volatile substances and/or to incur thermal decomposition. The root of the word calcination refers to its most prominent use, which is to remove carbon from limestone (calcium carbonate) through combustion to yield calcium oxide (quicklime). This calcination reaction is CaCO3(s) → CaO(s) + CO2(g). Calcium oxide is a crucial ingredient in modern cement, and is also used as a chemical flux in smelting. Industrial calcination generally emits carbon dioxide (), making it a major contributor to climate change. A calciner is a steel cylinder that rotates inside a heated furnace and performs indirect high-temperature processing (550–1150 °C, or 1000–2100 °F) within a contro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Peroxide
Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscous than water. It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%–6% by weight) in water for consumer use, and in higher concentrations for industrial use. Concentrated hydrogen peroxide, or " high-test peroxide", decomposes explosively when heated and has been used as a propellant in rocketry. Hydrogen peroxide is a reactive oxygen species and the simplest peroxide, a compound having an oxygen–oxygen single bond. It decomposes slowly when exposed to light, and rapidly in the presence of organic or reactive compounds. It is typically stored with a stabilizer in a weakly acidic solution in a dark bottle to block light. Hydrogen peroxide is found in biological systems including the human body. Enzymes that use or decompose hydrogen peroxide are classified as peroxidases. Properties The boiling p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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