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Arsonic Acid
Arsonic acid is the simplest of the arsonic acids. It is a hypothetical compound, although the tautomeric arsenious acid (As(OH)3) is well established. In contrast to the instability of HAsO(OH)2, the phosphorus compound with analogous stoichiometry exists as the tetrahedral tautomer. Similarly, organic derivatives such as phenylarsonic acid are tetrahedral with pentavalent central atom. There are similar acids that are the same except for having different pnictogens , - ! colspan=2 style="text-align:left;" , ↓ Period (periodic table), Period , - ! Period 2 element, 2 , , - ! Period 3 element, 3 , , - ! Period 4 element, 4 , , - ! Period 5 element, 5 , , - ! Period 6 element, 6 , , - ! Perio .... The phosphorus equivalent is phosphonic acid. References Arsonic acids Hypothetical chemical compounds {{acid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Society Of Chemistry
The Royal Society of Chemistry (RSC) is a learned society and professional association in the United Kingdom with the goal of "advancing the chemistry, chemical sciences". It was formed in 1980 from the amalgamation of the Chemical Society, the Royal Institute of Chemistry, the Faraday Society, and the Society for Analytical Chemistry with a new Royal Charter and the dual role of learned society and professional body. At its inception, the Society had a combined membership of 49,000 in the world. The headquarters of the Society are at Burlington House, Piccadilly, London. It also has offices in Thomas Graham House in Cambridge (named after Thomas Graham (chemist), Thomas Graham, the first president of the Chemical Society) where ''RSC Publishing'' is based. The Society has offices in the United States, on the campuses of The University of Pennsylvania and Drexel University, at the University City Science Center in Philadelphia, Pennsylvania, in both Beijing and Shanghai, People' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arsonic Acids
Arsonic acids are a subset of organoarsenic compounds defined as oxyacids where a pentavalent arsenic atom is bonded to two hydroxyl groups, a third oxygen atom (this one with a double bond), and an organic substituent. The salts/conjugate bases of arsonic acids are called arsonates. Like all arsenic-containing compounds, arsonic acids are toxic and carcinogenic to humans. Arsonic acid refers to , the case where the substituent is a single hydrogen atom. The other arsonic acids can simply be viewed as hydrocarbyl derivatives of this base case. Arsenic acid results when the substituent is a hydroxyl group. Methylarsonic acid results when the substituent is a methyl group. Phenylarsonic acid results when the substituent is a phenyl group. Syntheses The Béchamp reaction is used to produce arsonic acids from activated aromatic substrates. The reaction is an electrophilic aromatic substitution, using arsenic acid as the electrophile. The reaction proceeds according to this idea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypothetical Compound
A hypothetical chemical compound is a chemical compound that has been conceived of, but is not known to have been synthesized, observed, or isolated (identified or shown to exist). Some hypothetical compounds cannot form at all, due to steric effects (e.g. tetra-''tert''-butylmethane, , chlorine heptafluoride, , or bromine heptafluoride, ) or bond stress (e.g. tetrahedrane ). Others might turn out to be highly unstable, decomposing, isomerizing, polymerizing, rearranging, or disproportionating. Some are thought to exist only briefly as reactive intermediates or in vacuum. Some have no known pathway for synthesis (e.g. hypercubane). Some compounds of radioactive elements have never been synthesized due to their radioactive decay and short half-lives (e.g. francium hydroxide FrOH, radon hexafluoride , astatine heptafluoride , polonium(II) fluoride ). Some "parent compounds" have not been or cannot be isolated, even though stable structural analogs with substituents have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tautomer
In chemistry, tautomers () are structural isomers (constitutional isomers) of chemical compounds that readily interconvert. The chemical reaction interconverting the two is called tautomerization. This conversion commonly results from the relocation of a hydrogen atom within the compound. The phenomenon of tautomerization is called tautomerism, also called desmotropism. Tautomerism is for example relevant to the behavior of amino acids and nucleic acids, two of the fundamental building blocks of life. Care should be taken not to confuse tautomers with depictions of "contributing structures" in chemical resonance. Tautomers are distinct chemical species that can be distinguished by their differing atomic connectivities, molecular geometries, and physicochemical and spectroscopic properties, whereas resonance forms are merely alternative Lewis structure (valence bond theory) depictions of a single chemical species, whose true structure is a quantum superposition, essentially the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arsenious Acid
Arsenous acid (or arsorous acid) is the inorganic compound with the formula H3AsO3. It is known to occur in aqueous solutions, but it has not been isolated as a pure material, although this fact does not detract from the significance of As(OH)3. Properties As(OH)3 is a pyramidal molecule consisting of three hydroxyl groups bonded to arsenic. The 1H NMR spectrum of arsenous acid solutions consists of a single signal consistent with the molecule's high symmetry. In contrast, the nominally related phosphorous acid H3PO3 adopts the structure HPO(OH)2. The structural analogue of arsenous acid (P(OH)3) is a very minor equilibrium component of such solutions. The differing behaviors of the As and P compounds reflect a trend whereby high oxidation states are more stable for lighter members of main group elements than their heavier congeners. One tautomer of arsenous acid is HAsO(OH)2, which is called arsonic acid. It has not been isolated or well-characterized. Synthesis The preparati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenylarsonic Acid
Phenylarsonic acid is the chemical compound with the formula C6H5AsO(OH)2, commonly abbreviated PhAsO3H2. This colourless solid is an organic derivative of arsenic acid, AsO(OH)3, where one OH group has been replaced by a phenyl group. The compound is a buffering agent and a precursor to other organoarsenic compounds, some of which are used in animal nutrition, e.g. 4-hydroxy-3-nitrobenzenearsonic acid. Preparation and structure PhAsO3H2 can be prepared in several routes, but a common one entails treatment of phenyl diazonium salts with sodium arsenite (prepared from arsenious acid and base) in the presence of a copper(II) catalyst. : + NaAsO3H2 → C6H5AsO3H2 + Na+ + N2 Related derivatives are prepared similarly. It was first prepared by Michaelis and Loenser. X-ray crystallography indicates that the molecules are connected by hydrogen-bonds consistent with short distance of 2.5 Å separating the oxygen atoms. The arsenic center is tetrahedral.Struchkov, Yu. T. "Cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pnictogen
, - ! colspan=2 style="text-align:left;" , ↓ Period , - ! 2 , , - ! 3 , , - ! 4 , , - ! 5 , , - ! 6 , , - ! 7 , , - , colspan="2", ---- ''Legend'' A pnictogen ( or ; from "to choke" and -gen, "generator") is any of the chemical elements in group 15 of the periodic table. Group 15 is also known as the nitrogen group or nitrogen family. Group 15 consists of the elements nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), bismuth (Bi), and moscovium (Mc). The IUPAC has called it Group 15 Since 1988. Before that, in America it was called Group VA, owing to a text by H. C. Deming and the Sargent-Welch Scientific Company, while in Europe it was called ecommended that in 1970. (Pronounced "group five A" and "group five B"; "V" is the Roman numeral 5). In semiconductor physics, it is still usually called Group V. The "five" ("V") in the historical names comes from the " pentavalency" of nitrogen, reflected by the stoichiometry of compou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arsonic Acids
Arsonic acids are a subset of organoarsenic compounds defined as oxyacids where a pentavalent arsenic atom is bonded to two hydroxyl groups, a third oxygen atom (this one with a double bond), and an organic substituent. The salts/conjugate bases of arsonic acids are called arsonates. Like all arsenic-containing compounds, arsonic acids are toxic and carcinogenic to humans. Arsonic acid refers to , the case where the substituent is a single hydrogen atom. The other arsonic acids can simply be viewed as hydrocarbyl derivatives of this base case. Arsenic acid results when the substituent is a hydroxyl group. Methylarsonic acid results when the substituent is a methyl group. Phenylarsonic acid results when the substituent is a phenyl group. Syntheses The Béchamp reaction is used to produce arsonic acids from activated aromatic substrates. The reaction is an electrophilic aromatic substitution, using arsenic acid as the electrophile. The reaction proceeds according to this idea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
