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Gold(III) Sulfide
Gold(III) sulfide or auric sulfide is an inorganic compound with the formula .Auric sulfide has been described as a black and amorphous. Little evidence has been published supporting the existence of macroscopic quantities of this material. Claims Early investigations claimed to prepare auric sulfide by the reaction of lithium tetrachloroaurate with hydrogen sulfide: : Similar preparations via chloroauric acid, auric chloride, or gold(III) sulfate a claimed proceed in anhydrous solvents, but water evinces a redox decomposition into metallic gold in sulfuric acid: : Conversely, ''cyclo''-octasulfur reduces gold(III) sulfate to a mixture of gold sulfides and sulfur oxides: : Auric sulfide has also been claimed as the product when auric acetate is sonicated with ''cyclo''-octasulfur in decalin. Auric sulfide is claimed to react with nitric acid as well sodium cyanide. It is claimed to dissolve in concentrated sodium sulfide Sodium sulfide is a chemical compound with the fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gold
Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile metal in a pure form. Chemically, gold is a transition metal and a group 11 element. It is one of the least reactive chemical elements and is solid under standard conditions. Gold often occurs in free elemental ( native state), as nuggets or grains, in rocks, veins, and alluvial deposits. It occurs in a solid solution series with the native element silver (as electrum), naturally alloyed with other metals like copper and palladium, and mineral inclusions such as within pyrite. Less commonly, it occurs in minerals as gold compounds, often with tellurium ( gold tellurides). Gold is resistant to most acids, though it does dissolve in aqua regia (a mixture of nitric acid and hydrochloric acid), forming a soluble tetrachloro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclo-octasulfur
Octasulfur is an inorganic substance with the chemical formula . It is an odourless and tasteless yellow solid, and is a major industrial chemical. It is the most common allotrope of sulfur and occurs widely in nature.Steudel, R., "Homocyclic Sulfur Molecules", Topics Curr. Chem. 1982, 102, 149. Nomenclature The name octasulfur is the most commonly used for this chemical. It is systematically named ''cyclo''-octasulfur (which is the preferred IUPAC name) and cyclooctasulfane. It is also the final member of the thiocane heterocylic series, where every carbon atom is substituted with a sulfur atom, thus this sulfur allotrope is systematically named octathiocane as well. Structure The chemical consists of rings of 8 sulfur atoms. It adopts a crown conformation with D4d point group symmetry. The S–S bond lengths are equal, at about 2.05 Å. Octasulfur crystallizes in three distinct polymorphs: rhombohedral, and two monoclinic forms, of which only two are stable at standard ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gold(III) Compounds
Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile metal in a pure form. Chemically, gold is a transition metal and a group 11 element. It is one of the least reactive chemical elements and is solid under standard conditions. Gold often occurs in free elemental (native state), as nuggets or grains, in rocks, veins, and alluvial deposits. It occurs in a solid solution series with the native element silver (as electrum), naturally alloyed with other metals like copper and palladium, and mineral inclusions such as within pyrite. Less commonly, it occurs in minerals as gold compounds, often with tellurium (gold tellurides). Gold is resistant to most acids, though it does dissolve in aqua regia (a mixture of nitric acid and hydrochloric acid), forming a soluble tetrachloroaurate anion. Gold is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gold(I) Sulfide
Gold(I) sulfide is the inorganic compound with the formula . It is the principal sulfide of gold. It decomposes to gold metal and elemental sulfur, illustrating the "nobility" of gold. Structure and preparation The compound crystallizes in the motif seen for cuprous oxide: gold is 2-coordinate, sulfur 4-coordinate, and the S-Au-S linkage is linear. Linear coordination geometry is typical of gold(I) compounds, e.g. the coordination complex chloro(dimethyl sulfide)gold(I). The structure is similar to the α form of silver sulfide (argentite), which only exists at high temperatures. It can be prepared by treating gold chloride with 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 under ... It also arises by sulfiding dicyanoaurate: : This product is described as "initially ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Sulfide
Sodium sulfide is a chemical compound with the formula Na2 S, or more commonly its hydrate Na2S·9 H2O. Both the anhydrous and the hydrated salts in pure crystalline form are colorless solids, although technical grades of sodium sulfide are generally yellow to brick red owing to the presence of polysulfides and commonly supplied as a crystalline mass, in flake form, or as a fused solid. They are water-soluble, giving strongly alkaline solutions. When exposed to moist air, Na2S and its hydrates emit hydrogen sulfide, an extremely toxic, flammable and corrosive gas which smells like rotten eggs. Some commercial samples are specified as Na2S·''x''H2O, where a weight percentage of Na2S is specified. Commonly available grades have around 60% Na2S by weight, which means that ''x'' is around 3. These grades of sodium sulfide are often marketed as 'sodium sulfide flakes'. Structure Na2S adopts the antifluorite structure, which means that the Na+ centers occupy sites of the fluoride ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Cyanide
Sodium cyanide is a poisonous compound with the formula Na C N. It is a white, water-soluble solid. Cyanide has a high affinity for metals, which leads to the high toxicity of this salt. Its main application, in gold mining, also exploits its high reactivity toward metals. It is a moderately strong base. Production and chemical properties Sodium cyanide is produced by treating hydrogen cyanide with sodium hydroxide: :HCN + NaOH → NaCN + H2O Worldwide production was estimated at 500,000 tons in the year 2006. Formerly it was prepared by the Castner process involving the reaction of sodium amide with carbon at elevated temperatures. : NaNH2 + C → NaCN + H2 The structure of solid NaCN is related to that of sodium chloride. The anions and cations are each six-coordinate. Potassium cyanide (KCN) adopts a similar structure. When treated with acid, it forms the toxic gas hydrogen cyanide: : NaCN + H+ → HCN + Na+ Because the salt is derived from a weak acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitric Acid
Nitric acid is the inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but older samples tend to be yellow cast due to decomposition into oxides of nitrogen. Most commercially available nitric acid has a concentration of 68% in water. When the solution contains more than 86% , it is referred to as ''fuming nitric acid''. Depending on the amount of nitrogen dioxide present, fuming nitric acid is further characterized as red fuming nitric acid at concentrations above 86%, or white fuming nitric acid at concentrations above 95%. Nitric acid is the primary reagent used for nitration – the addition of a nitro group, typically to an organic molecule. While some resulting nitro compounds are shock- and thermally-sensitive explosives, a few are stable enough to be used in munitions and demolition, while others are still more stable and used as pigments in inks and dyes. Nitric acid is also commonly used as a strong oxidiz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decalin
Decalin (decahydronaphthalene, also known as bicyclo .4.0ecane and sometimes decaline), a bicyclic organic compound, is an industrial solvent. A colorless liquid with an aromatic odor, it is used as a solvent for many resins or fuel additives. Isomers Decalin occurs in ''cis'' and ''trans'' forms. The ''trans'' form is energetically more stable because of fewer steric interactions. ''cis''-Decalin is a chiral molecule without a chiral center; it has a two-fold rotational symmetry axis, but no reflective symmetry. However, the chirality is canceled through a chair-flipping process that turns the molecule into its mirror image. Image:Cis-trans isomerism of decahydronaphthalene.svg, Image:cis-decalin double chair.png, 2: Image:trans-decalin double chair.png, 3: File:Cisdecalin conformations.png, 4: ''trans''-Decalin The only possible way to join the two six-membered rings in the ''trans'' position means the second ring needs to start from two equatorial bonds (blue) of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auric Acetate
Gold(III) acetate, also known as auric acetate, is a chemical compound of gold and acetic acid. It is a yellow solid that decomposes at 170 °C to gold metal. This decomposition of gold(III) acetate has been studied as a pathway to produce gold nanoparticles as catalysts. Production and reactions Gold(III) acetate can be produced by the reaction of gold(III) hydroxide and glacial acetic acid: :Au(OH)3 + 3CH3COOH → Au(CH3COO)3 + 3H2O It reacts with 2-(''p''-tolyl)pyridine (tpy) in presence of trifluoroacetic acid to form Au(CF3COO)2(tpy). Gold(III) sulfide Gold(III) sulfide or auric sulfide is an inorganic compound with the formula .Auric sulfide has been described as a black and amorphous. Little evidence has been published supporting the existence of macroscopic quantities of this material. Clai ... has been claimed as the product when gold(III) acetate is sonicated with ''cyclo''-octasulfur in decalin. References {{Acetates Gold(III) compounds Acetates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfuric Acid
Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid ( Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen and hydrogen, with the molecular formula . It is a colorless, odorless and viscous liquid that is miscible with water. Pure sulfuric acid does not exist naturally on Earth due to its strong affinity to water vapor; it is hygroscopic and readily absorbs water vapor from the air. Concentrated sulfuric acid is highly corrosive towards other materials, from rocks to metals, since it is an oxidant with powerful dehydrating properties. Phosphorus pentoxide is a notable exception in that it is not dehydrated by sulfuric acid, but to the contrary dehydrates sulfuric acid to sulfur trioxide. Upon addition of sulfuric acid to water, a considerable amount of heat is released; thus the reverse procedure of adding water to the acid should not be performed since the heat released ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfur
Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula S8. Elemental sulfur is a bright yellow, crystalline solid at room temperature. Sulfur is the tenth most abundant element by mass in the universe and the fifth most on Earth. Though sometimes found in pure, native form, sulfur on Earth usually occurs as sulfide and sulfate minerals. Being abundant in native form, sulfur was known in ancient times, being mentioned for its uses in ancient India, ancient Greece, China, and ancient Egypt. Historically and in literature sulfur is also called brimstone, which means "burning stone". Today, almost all elemental sulfur is produced as a byproduct of removing sulfur-containing contaminants from natural gas and petroleum.. Downloahere The greatest commercial use of the element is the production ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metallic Gold
Gold, also called golden, is a color tone resembling the gold chemical element. The web color ''gold'' is sometimes referred to as ''golden'' to distinguish it from the color ''metallic gold''. The use of ''gold'' as a color term in traditional usage is more often applied to the color "metallic gold" (shown below). The first recorded use of ''golden'' as a color name in English was in 1300 to refer to the element gold. The word ''gold'' as a color name was first used in 1400 and in 1423 to refer to blond hair.Maerz and Paul ''A Dictionary of Color'' New York:1930 McGraw-Hill Page 195 Metallic gold, such as in paint, is often called goldtone or gold tone, or gold ground when describing a solid gold background. In heraldry, the French word or is used. In model building, the color gold is different from brass. A shiny or metallic silvertone object can be painted with transparent yellow to obtain goldtone, something often done with Christmas decorations. Metallic gold Gol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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