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Cobalt(II) Sulfide
Cobalt sulfide is the name for chemical compounds with a formula CoxSy. Well-characterized species include minerals with the formula CoS, CoS2, Co3S4, and Co9S8. In general, the sulfides of cobalt are black, semiconducting, insoluble in water, and nonstoichiometric.John D. Donaldson, Detmar Beyersmann "Cobalt and Cobalt Compounds" in Ullmann's Encyclopedia of Industrial Chemistry 2005, Wiley-VCH, Weinheim. Minerals and hydrometallurgy Cobalt sulfides occur widely as minerals, comprising major sources of all cobalt compounds. Binary cobalt sulfide minerals include the cattierite (CoS2) and linnaeite (Co3S4). CoS2 (see image in table) is isostructural with iron pyrite, featuring disulfide groups, i.e. Co2+S22−. Linnaeite, also rare, adopts the spinel motif. The Co9S8 compound is known as a very rare cobaltpentlandite (the Co analogue of pentlandite). Mixed metal sulfide minerals include carrollite (CuCo2S4) and siegenite (Co3−xNixS4). CoS is known as jaipurite. However ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element is therefore not a compound. A compound can be transformed into a different substance by a chemical reaction, which may involve interactions with other substances. In this process, bonds between atoms may be broken and/or new bonds formed. There are four major types of compounds, distinguished by how the constituent atoms are bonded together. Molecular compounds are held together by covalent bonds; ionic compounds are held together by ionic bonds; intermetallic compounds are held together by metallic bonds; coordination complexes are held together by coordinate covalent bonds. Non-stoichiometric compounds form a disputed marginal case. A chemical formula specifies the number of atoms of each element in a compound molecule, using the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semi-conductor
A semiconductor is a material which has an electrical conductivity value falling between that of a conductor, such as copper, and an insulator, such as glass. Its resistivity falls as its temperature rises; metals behave in the opposite way. Its conducting properties may be altered in useful ways by introducing impurities (" doping") into the crystal structure. When two differently doped regions exist in the same crystal, a semiconductor junction is created. The behavior of charge carriers, which include electrons, ions, and electron holes, at these junctions is the basis of diodes, transistors, and most modern electronics. Some examples of semiconductors are silicon, germanium, gallium arsenide, and elements near the so-called " metalloid staircase" on the periodic table. After silicon, gallium arsenide is the second-most common semiconductor and is used in laser diodes, solar cells, microwave-frequency integrated circuits, and others. Silicon is a critical element for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Non-stoichiometric Compound
In chemistry, non-stoichiometric compounds are chemical compounds, almost always solid inorganic compounds, having elemental composition whose proportions cannot be represented by a ratio of small natural numbers (i.e. an empirical formula); most often, in such materials, some small percentage of atoms are missing or too many atoms are packed into an otherwise perfect lattice work. Contrary to earlier definitions, modern understanding of non-stoichiometric compounds view them as homogeneous, and not mixtures of stoichiometric chemical compounds. Since the solids are overall electrically neutral, the defect is compensated by a change in the charge of other atoms in the solid, either by changing their oxidation state, or by replacing them with atoms of different elements with a different charge. Many metal oxides and sulfides have non-stoichiometric examples; for example, stoichiometric iron(II) oxide, which is rare, has the formula , whereas the more common material is nonstoichi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cattierite
Cattierite (CoS2) is a cobalt sulfide mineral found in the Democratic Republic of Congo. It was discovered together with the nickel sulfide vaesite by Johannes F. Vaes, a Belgian mineralologist and named after Felicien Cattier, who was chairman of the board of the Union Minière du Haut-Katanga. The mineral belongs to the pyrite group, in which all minerals share the same building principle. The metal in the oxidation state +2 forms a sodium chloride structure together with the anion S22−. This formalism recognizes that the sulfur atoms in pyrite occur in pairs with clear S-S bonds. It occurs with pyrite, chalcopyrite and members of the linnaeite – polydymite group in ore deposits in carbonate rocks. In addition to the type locality in the Katanga district it is reported from Gansberg, Black Forest, Germany; near Filipstad, Varmland, Sweden; Bald Knob, near Sparta, Alleghany County, North Carolina and in the Fletcher mine of Reynolds County, Missouri Reynolds County is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linnaeite
Linnaeite is a cobalt sulfide mineral with the composition Co+2Co+32S4. It was discovered in 1845 in Västmanland, Sweden, and was named to honor Carl Linnaeus (1707–1778). Linnaeite forms a series with polydymite Polydymite, Ni2+Ni23+S4, is a supergene thiospinel sulfide mineral associated with the weathering of primary pentlandite nickel sulfide. Polydymite crystallises in the isometric system, with a hardness of 4.5 to 5.5 and a specific gravity of ab ..., Ni+2Ni+32S4. Linnaeite is found in hydrothermal veins with other cobalt and nickel sulfides in many localities around the world. References * Cobalt minerals Thiospinel group Cubic minerals Minerals in space group 227 Commemoration of Carl Linnaeus {{sulfide-mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrite
The mineral pyrite (), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Iron, FeSulfur, S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. Pyrite's metallic Luster (mineralogy), luster and pale brass-yellow hue give it a superficial resemblance to gold, hence the well-known nickname of ''fool's gold''. The color has also led to the nicknames ''brass'', ''brazzle'', and ''Brazil'', primarily used to refer to pyrite found in coal. The name ''pyrite'' is derived from the Greek language, Greek (), 'stone or mineral which strikes fire', in turn from (), 'fire'. In ancient Roman times, this name was applied to several types of stone that would create sparks when struck against steel; Pliny the Elder described one of them as being brassy, almost certainly a reference to what we now call pyrite. By Georgius Agricola's time, , the term had become a generic term for all of the pyrite group, sulfide minerals. Pyrite is usua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinel
Spinel () is the magnesium/aluminium member of the larger spinel group of minerals. It has the formula in the cubic crystal system. Its name comes from the Latin word , which means ''spine'' in reference to its pointed crystals. Properties Spinel crystallizes in the isometric system; common crystal forms are octahedra, usually twinned. It has no true cleavage, but shows an octahedral parting and a conchoidal fracture. Its hardness is 8, its specific gravity is 3.5–4.1, and it is transparent to opaque with a vitreous to dull luster. It may be colorless, but is usually various shades of red, lavender, blue, green, brown, black, or yellow. Some spinels are among the most famous gemstones; among them are the Black Prince's Ruby and the "Timur ruby" in the British Crown Jewels, and the "Côte de Bretagne", formerly from the French Crown jewels. The Samarian Spinel is the largest known spinel in the world, weighing . The transparent red spinels were called spinel-rubies or b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentlandite
Pentlandite is an iron–nickel sulfide with the chemical formula . Pentlandite has a narrow variation range in Ni:Fe but it is usually described as having a Ni:Fe of 1:1. It also contains minor cobalt, usually at low levels as a fraction of weight. Pentlandite forms isometric crystals, but it is normally found in massive granular aggregates. It is brittle with a hardness of 3.5–4 and specific gravity of 4.6–5.0 and is non-magnetic. It has a yellowish bronze color. Pentlandite is the most important source of mined nickel. Name and discovery It is named after the Irish scientist Joseph Barclay Pentland (1797–1873), who first noted the mineral. Paragenesis Pentlandite is the most common terrestrial nickel sulfide. It typically forms during cooling of a sulfide melt. These sulfide melts, in turn, are typically formed during the evolution of a silicate melt. Because Ni is a chalcophile-like element, it has preference for (i.e. it "partitions into") sulfide phases. In sul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carrollite
Carrollite, CuCo2S4, is a sulfide of copper and cobalt, often with substantial substitution of nickel for the metal ions, and a member of the linnaeite group. It is named after the type locality in Carroll County, Maryland, US, at the Patapsco mine, Sykesville. Unit cell Space group: Fd3m. Unit cell parameters = a = 9.48 Å, Z = 8. Unit cell volume: V = 851.97 Å3 (calculated from unit cell parameters).Gaines et al (1997) Dana's New Mineralogy Eighth Edition. Wiley Linnaeite group The linnaeite group is a group of sulfides and selenides with the general formula AB2X4 in which X is sulfur or selenium, A is divalent Fe, Ni, Co or Cu and B is trivalent Co, Ni or, for daubréelite, Cr. The minerals are isometric, space group Fd3m and isostructural with each other and with minerals of the spinel group. The structure of the linnaeite group consists of a cubic close packed array of X (X is oxygen in the spinels and sulfur or selenium in the linnaeite group). Wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siegenite
Siegenite (also called grimmite, or nickel cobalt sulfide) is a ternary transition metal dichalcogenide compound with the chemical formula (Ni,Co)3S4. It has been actively studied as a promising material system for electrodes in electrochemical energy applications due to its better conductivity, greater mechanical and thermal stability, and higher performance compared to metal oxides currently in use. Potential applications of this material system include supercapacitors, batteries, electrocatalysis, dye-sensitized solar cells, photocatalysis, glucose sensors, and microwave absorption. In synthetic chemistry, a range of chemical compositions with the formula NixCo3-xS4 (0 < x < 3) are often referred to as the siegenite system. However, according to the new IMA list of minerals (updated November 2022), the normal spinel NiCo2S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Sulfide
Hydrogen sulfide is a chemical compound with the formula . It is a colorless chalcogen-hydride gas, and is poisonous, corrosive, and flammable, with trace amounts in ambient atmosphere having a characteristic foul odor of rotten eggs. The underground mine gas term for foul-smelling hydrogen sulfide-rich gas mixtures is ''stinkdamp''. Swedish chemist Carl Wilhelm Scheele is credited with having discovered the chemical composition of purified hydrogen sulfide in 1777. The British English spelling of this compound is hydrogen sulphide, a spelling no longer recommended by the Royal Society of Chemistry or the International Union of Pure and Applied Chemistry. Hydrogen sulfide is toxic to humans and most other animals by inhibiting cellular respiration in a manner similar to hydrogen cyanide. When it is inhaled or it or its salts are ingested in high amounts, damage to organs occurs rapidly with symptoms ranging from breathing difficulties to convulsions and death. Despite this, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Qualitative Inorganic Analysis
Classical qualitative inorganic analysis is a method of analytical chemistry which seeks to find the elemental composition of inorganic compounds. It is mainly focused on detecting ions in an aqueous solution, therefore materials in other forms may need to be brought to this state before using standard methods. The solution is then treated with various reagents to test for reactions characteristic of certain ions, which may cause color change, precipitation and other visible changes. Qualitative inorganic analysis is that branch or method of analytical chemistry which seeks to establish the elemental composition of inorganic compounds through various reagents. Physical appearance of inorganic salts Detecting cations According to their properties, cations are usually classified into six groups. Each group has a common reagent which can be used to separate them from the solution. To obtain meaningful results, the separation must be done in the sequence specified below, as some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
