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Arsenic organic compounds

Arsenate Poisoning Arsenate is structurally and chemically similar to inorganic phosphate (P4), and many enzymes that require phosphate will also use arsenate. Organic compounds of arsenate are less stable than analogous phosphate compounds, however. For example, acyl arsenates decompose rapidly by hydrolysis ... [Pg.557]

ARSENIC, ORGANIC COMPOUNDS (as As) (Organic arsenic compounds have variable molecular formulas and variable formula weights depending upon the specific organic arsenic compound. The mo-lecular formula for arsenic is As. Its corresponding formula weight is 74.92). [Pg.416]

In tissues of chondrichthyans (fish with a cartilaginous skeleton, such as sharks and rays), many species of marine fish (cod, flatfish, mackerel, herring, salmon and others), crustaceans (e.g. lobsters, shrimps and crabs) and molluscs (e.g. mussels and scallops), arsenobetaine is the main arsenic organic compound. [Pg.426]

CWS-4. funeral Method of Synthesis of Certain Non-Arsenical Organic Compounds Including Several Specific Compounds. [Pg.42]

Lead oxide is used in producing fine "crystal glass" and "flint glass" of a high index of refraction for achromatic lenses. The nitrate and the acetate are soluble salts. Lead salts such as lead arsenate have been used as insecticides, but their use in recent years has been practically eliminated in favor of less harmful organic compounds. [Pg.86]

G. T. Morgan, Organic Compounds of Arsenic and Antimony, Longmans, Green and Co., London, UK, 1918. [Pg.341]

Heteropolyacids (HPA) are the unique class of inorganic complexes. They are widely used in different areas of science in biochemistry for the precipitation of albumens and alkaloids, in medicine as anticarcinogenic agents, in industry as catalysts. HPA are well known analytical reagents for determination of phosphoms, silica and arsenic, nitrogen-containing organic compounds, oxidants and reductants in solution etc. [Pg.60]

In catalytic incineration, there are limitations concerning the effluent streams to be treated. Waste gases with organic compound contents higher than 20% of LET (lower explosion limit) are not suitable, as the heat content released in the oxidation process increases the catalyst bed temperature above 650 °C. This is normally the maximum permissible temperature to which a catalyst bed can be continuously exposed. The problem is solved by dilution-, this method increases the furnace volume and hence the investment and operation costs. Concentrations between 2% and 20% of LET are optimal, The catalytic incinerator is not recommended without prefiltration for waste gases containing particulate matter or liquids which cannot be vaporized. The waste gas must not contain catalyst poisons, such as phosphorus, arsenic, antimony, lead, zinc, mercury, tin, sulfur, or iron oxide.(see Table 1.3.111... [Pg.1258]

Other examples are the use of osmium(VIII) oxide (osmium tetroxide) as catalyst in the titration of solutions of arsenic(III) oxide with cerium(IV) sulphate solution, and the use of molybdate(VI) ions to catalyse the formation of iodine by the reaction of iodide ions with hydrogen peroxide. Certain reactions of various organic compounds are catalysed by several naturally occurring proteins known as enzymes. [Pg.19]

Sublimation. This process is employed to separate volatile substances from non-volatile impurities. Iodine, arsenic(III) oxide, ammonium chloride and a number of organic compounds can be purified in this way. The material to be purified is gently heated in a porcelain dish, and the vapour produced is condensed on a flask which is kept cool by circulating cold water inside it. [Pg.106]

To be useful as CVD precursors, a metallo-organic compound should be stable at room temperature so that its storage and transfer are not a problem. It should also decompose readily at low temperature, i.e., below 500°C. The compounds listed in Table 4.1 meet these conditions with the exception of the alkyls of arsenic and phosphorus, which decompose at higher temperatures. For that reason, the hydrides of arsenic and phosphorus are often preferred as CVD precursors (see Ch. 3). These hydrides however are extremely toxic and environmental considerations may restrict their use. [Pg.88]

The biological cycle of arsenic in the surface ocean involves the uptake of arsenate by plankton, the conversion of arsenate to a number of as yet unidentified organic compounds, and the release of arsenite and methylated species into the seawater. Biological demethylation of the methyl-arsenicals and the oxidation of arsenite by as yet... [Pg.398]

Arsenic. The presence of arsenic in an organic compound is generally revealed by the formation of a dull grey mirror of arsenic on the walls of the test-tube when the compound is fusM with sodium in the Lassaigne test. Usually sufficient arsenic is found in the fusion solution to give a yellow precipitate of arsenic trisulphide when the solution is acidified with hydrochloric acid and treated with hydrogen sulphide. [Pg.1043]

It is however true to say that the structures of a wide variety of organic compounds can be solved using just NMR spectroscopy, which provides a huge arsenal of measurement techniques in one to three dimensions. To de-... [Pg.220]

Another organic compound of arsenic that is of historical significance was discovered in 1901 by P. Ehrlich. That compound is known as arsphenamine or Salvarsan, which has the structure... [Pg.410]

As was the case with the volume The chemistry of organic arsenic, antimony and bismuth compounds, published in 1994, it was clear that the set of five volumes describing organometallic compounds (edited by Professor Frank R. Hartley) did not deal in sufficient depth with organic compounds of germanium, tin and lead. Hence we decided to publish the present volume, which we hope will be a useful and worthwhile addition to the series The Chemistry of Functional Groups. In this volume the authors literature search extended in most cases up to the end of 1994. [Pg.1004]

The toxicity of arsenicals conforms to the following order, from greatest to least toxicity arsines > inorganic arsenites > organic trivalent compounds (arsenoxides) > inorganic arsenates > organic pentavalent compounds > arsonium compounds > elemental arsenic. [Pg.1484]


See other pages where Arsenic organic compounds is mentioned: [Pg.1008]    [Pg.1033]    [Pg.21]    [Pg.74]    [Pg.304]    [Pg.1008]    [Pg.1033]    [Pg.21]    [Pg.74]    [Pg.304]    [Pg.42]    [Pg.42]    [Pg.1038]    [Pg.25]    [Pg.164]    [Pg.326]    [Pg.201]    [Pg.20]    [Pg.981]    [Pg.649]    [Pg.793]    [Pg.806]    [Pg.155]    [Pg.156]    [Pg.590]    [Pg.593]    [Pg.1038]    [Pg.22]    [Pg.49]    [Pg.818]    [Pg.3]    [Pg.456]    [Pg.377]    [Pg.892]    [Pg.1486]    [Pg.1512]   


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Arsenic Acid Organic Compounds

Arsenic compounds

Arsenic compounds arsenate

Arsenic organic

Arsenic organic arsenicals

Arsenic organisms

Arsenic, in organic compounds

Organic arsenicals compounds, determination

Organic arsenicals mercury compounds

Organic arsenicals sulphur compounds

Organic compounds of arsenic

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