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Thiosulfate
Thiosulfate ( IUPAC-recommended spelling; sometimes thiosulphate in British English) is an oxyanion of sulfur with the chemical formula . Thiosulfate also refers to the compounds containing this anion, which are the salts of thiosulfuric acid, such as sodium thiosulfate and ammonium thiosulfate . Thiosulfate salts occur naturally. Thiosulfate rapidly dechlorinates water, and is used to halt bleaching in the paper-making industry. Thiosulfate salts are mainly used for dyeing in textiles, and bleaching of natural substances. Structure and bonding The thiosulfate ion is tetrahedral at the central S atom. The thiosulfate ion has C3v symmetry. The external sulfur atom has a valence of 2 while the central sulfur atom has a valence of 6. The oxygen atoms have a valence of 2. The S-S distance of about 201 pm in sodium thiosulphate is appropriate for a single bond. The S-O distances are slightly shorter than the S-O distances in sulfate. For many years, the oxidation states of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Thiosulfate
Sodium thiosulfate (sodium thiosulphate) is an inorganic compound with the formula . Typically it is available as the white or colorless pentahydrate (x = 5), which is a white solid that dissolves well in water. The compound is a reducing agent and a ligand, and these properties underpin its applications. Uses Sodium thiosulfate is used predominantly in dyeing. It converts some dyes to their soluble colorless "leuco" forms. It is also used to bleach "wool, cotton, silk, ...soaps, glues, clay, sand, bauxite, and... edible oils, edible fats, and gelatin." Medical uses Sodium thiosulfate is used in the treatment of cyanide poisoning. It is on the World Health Organization's List of Essential Medicines. Other uses include topical treatment of ringworm and tinea versicolor, and treating some side effects of hemodialysis and chemotherapy. In September 2022, the U.S. Food and Drug Administration (FDA) approved sodium thiosulfate under the trade name Pedmark to lessen the risk of oto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium Thiosulfate
Ammonium thiosulfate (ammonium thiosulphate in British English) is an inorganic compound with the formula . It is white crystalline solid with ammonia odor, readily soluble in water, slightly soluble in acetone and insoluble in ethanol and diethyl ether. Production It is produced by treating ammonium sulfite with sulfur at temperatures between 85 and 110 °C: : Applications Ammonium thiosulfate is used in photographic fixer. It is a so-called rapid fixer, acting more quickly than sodium thiosulfate fixers. Fixation involves these chemical reactions (illustrated for silver bromide): : : Also exploiting the stability of thiosulfate coordination complexes, ammonium thiosulfate is also used for leaching of gold and silver. It works with presence of copper as a catalyst. This process is a nontoxic alternative gold cyanidation. The advantage to ammonium thiosulfate is that the pyrolysis of its silver complexes leaves a residue solely of silver sulfide, in contrast to complexes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiosulfuric Acid
Thiosulfuric acid is the inorganic compound with the formula . It has attracted academic interest as a simple, easily accessed compound that is labile. It has few practical uses. Preparation and degradation The acid cannot be made by acidifying aqueous thiosulfate salt solutions as the acid readily decomposes in water. The decomposition products can include sulfur, sulfur dioxide, hydrogen sulfide, polysulfanes, sulfuric acid and polythionates, depending on the reaction conditions.. Anhydrous methods of producing the acid were developed by Max Schmidt: : : : The anhydrous acid also decomposes above −5 °C: : Structure The isomer is more stable than the isomer as established by Hartree–Fock/ ab initio calculations with a 6-311 G** basis set and MP2 to MP4 refinements. The theoretically predicted structure conforms with the double bond rule. An isomer of thiosulfuric acid is the adduct of hydrogen sulfide and sulfur trioxide Sulfur trioxide (alternative spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfur
Sulfur ( American spelling and the preferred IUPAC name) or sulphur ( Commonwealth spelling) is a chemical element; it has symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with the 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 common 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". Almost all elemental sulfur is produced as a byproduct of removing sulfur-containing contaminants from natural gas and petroleum.. Downloahere Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiosulfuric Acid
Thiosulfuric acid is the inorganic compound with the formula . It has attracted academic interest as a simple, easily accessed compound that is labile. It has few practical uses. Preparation and degradation The acid cannot be made by acidifying aqueous thiosulfate salt solutions as the acid readily decomposes in water. The decomposition products can include sulfur, sulfur dioxide, hydrogen sulfide, polysulfanes, sulfuric acid and polythionates, depending on the reaction conditions.. Anhydrous methods of producing the acid were developed by Max Schmidt: : : : The anhydrous acid also decomposes above −5 °C: : Structure The isomer is more stable than the isomer as established by Hartree–Fock/ ab initio calculations with a 6-311 G** basis set and MP2 to MP4 refinements. The theoretically predicted structure conforms with the double bond rule. An isomer of thiosulfuric acid is the adduct of hydrogen sulfide and sulfur trioxide Sulfur trioxide (alternative spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidation State
In chemistry, the oxidation state, or oxidation number, is the hypothetical Electrical charge, charge of an atom if all of its Chemical bond, bonds to other atoms are fully Ionic bond, ionic. It describes the degree of oxidation (loss of electrons) of an atom in a chemical compound. Conceptually, the oxidation state may be positive, negative or zero. Beside nearly-pure ionic bonding, many covalent bonds exhibit a strong ionicity, making oxidation state a useful predictor of charge. The oxidation state of an atom does not represent the "real" charge on that atom, or any other actual atomic property. This is particularly true of high oxidation states, where the ionization energy required to produce a multiply positive ion is far greater than the energies available in chemical reactions. Additionally, the oxidation states of atoms in a given compound may vary depending on Electronegativities of the elements (data page), the choice of electronegativity scale used in their calculation. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disproportionation
In chemistry, disproportionation, sometimes called dismutation, is a redox reaction in which one compound of intermediate oxidation state converts to two compounds, one of higher and one of lower oxidation state. The reverse of disproportionation, such as when a compound in an intermediate oxidation state is formed from precursors of lower and higher oxidation states, is called ''comproportionation'', also known as ''symproportionation''. More generally, the term can be applied to any desymmetrizing reaction where two molecules of one type react to give one each of two different types: : This expanded definition is not limited to redox reactions, but also includes some molecular autoionization reactions, such as the self-ionization of water. In contrast, some authors use the term ''redistribution'' to refer to reactions of this type (in either direction) when only ligand exchange but no redox is involved and distinguish such processes from disproportionation and comproportionati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Redox
Redox ( , , reduction–oxidation or oxidation–reduction) is a type of chemical reaction in which the oxidation states of the reactants change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. The oxidation and reduction processes occur simultaneously in the chemical reaction. There are two classes of redox reactions: * Electron transfer, Electron-transfer – Only one (usually) electron flows from the atom, ion, or molecule being oxidized to the atom, ion, or molecule that is reduced. This type of redox reaction is often discussed in terms of redox couples and electrode potentials. * Atom transfer – An atom transfers from one Substrate (chemistry), substrate to another. For example, in the rusting of iron, the oxidation state of iron atoms increases as the iron converts to an oxide, and simultaneously, the oxidation state of oxygen decreases as it accepts electrons r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidation
Redox ( , , reduction–oxidation or oxidation–reduction) is a type of chemical reaction in which the oxidation states of the reactants change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. The oxidation and reduction processes occur simultaneously in the chemical reaction. There are two classes of redox reactions: * Electron-transfer – Only one (usually) electron flows from the atom, ion, or molecule being oxidized to the atom, ion, or molecule that is reduced. This type of redox reaction is often discussed in terms of redox couples and electrode potentials. * Atom transfer – An atom transfers from one substrate to another. For example, in the rusting of iron, the oxidation state of iron atoms increases as the iron converts to an oxide, and simultaneously, the oxidation state of oxygen decreases as it accepts electrons released by the iron. Although oxidati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfur Oxoacid
Sulfur oxoacids are chemical compounds that contain sulfur, oxygen, and hydrogen Hydrogen is a chemical element; it has chemical symbol, symbol H and atomic number 1. It is the lightest and abundance of the chemical elements, most abundant chemical element in the universe, constituting about 75% of all baryon, normal matter .... The best known and most important industrially used is sulfuric acid. Sulfur has several oxoacids; however, some of these are known only from their salts (these are shown in italics in the table below). The acids that have been characterised contain a variety of structural features, for example: *tetrahedral sulfur when coordinated to oxygen *terminal and bridging oxygen atoms *terminal peroxo groups *terminal S=S *chains of (−S−)''n'' See also * Chlorosulfuric acid * Fluorosulfuric acid * Nitrosylsulfuric acid * Peroxydisulfuric acid * Sulfinic acids * Sulfonic acids References External links *{{MeSH name, Sulfur+Acids Sulfur oxoacids alo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfide
Sulfide (also sulphide in British English) is an inorganic anion of sulfur with the chemical formula S2− or a compound containing one or more S2− ions. Solutions of sulfide salts are corrosive. ''Sulfide'' also refers to large families of inorganic and organic compounds, e.g. lead sulfide and dimethyl sulfide. Hydrogen sulfide (H2S) and bisulfide (HS−) are the conjugate acids of sulfide. Chemical properties The sulfide ion does not exist in aqueous alkaline solutions of Na2S. Instead sulfide converts to hydrosulfide: :S2− + H2O → SH− + OH− Upon treatment with an acid, sulfide salts convert to hydrogen sulfide: :S2− + H+ → SH− :SH− + H+ → H2S Oxidation of sulfide is a complicated process. Depending on the conditions, the oxidation can produce elemental sulfur, polysulfides, polythionates, sulfite, or sulfate. Metal sulfides react with halogens, forming sulfur and metal salts. :8 MgS + 8 I2 → S8 + 8 MgI2 Metal de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
