Oxidation arsenous acid

Synonyms arsenic(V) oxide arsenic acid anhydride... 

If arsenious sulphide is used instead of the oxide, arsenic acid and sulphuric acid are formed and may be separated by precipitation of the latter by addition of lime. In the absence of nitric acid, oxygen at 20 atmospheres, even at 200° C., produces only arsenious acid from arsenious oxide (cf. p. 146), and arsenious and sulphuric acids from arsenious sulphide. 

ALUMINUM. PENTAKIS(N(sup 2)-ACETYL-L-GLUTAMINAT0)TETRAHYDR0XYTRI-ANDROST-4-EN-3-ONE, 17-beta-HYDROXY- 17-METHYL-7 ARSABICYCLO (2.2.1) HEPTA-2. 4, 6-TRIENE, 1-HYDROXY-, 1-OXIDE ARSENIC ACID (solution)... 

See directions preceding Exercise 58.) (a) Will dichromate ions oxidize arsenous acid, H3ASO5, to arsenic acid, HjAs04, in acid solution (b) Will dichromate ions oxidize hydrogen peroxide, H2O2, to free oxygen, O2, in acidic solution ... 

Nitrogen is unusual in forming so many oxides. The acidity of the Group V oxides falls from phosphorus, whose oxides are acidic, through arsenic and antimony whose oxides are amphoteric, to the basic oxide ofbismuth. This change is in accordance with the change from the non-metallic element, phosphorus, to the essentially metallic element, bismuth. The +5 oxides are found, in each case, to be more acidic than the corresponding + 3 oxides. 

In view of the high reactivity and sensitivity to oxidation of o-phenylone-diamine, the normal experimental conditions of the Skraup reaction are modified the condensation is carried out hi the presence of glycerol, arsenic acid solution and dilute sulphuric acid. 

Bromide ndIodide. The spectrophotometric determination of trace bromide concentration is based on the bromide catalysis of iodine oxidation to iodate by permanganate in acidic solution. Iodide can also be measured spectrophotometricaHy by selective oxidation to iodine by potassium peroxymonosulfate (KHSO ). The iodine reacts with colorless leucocrystal violet to produce the highly colored leucocrystal violet dye. Greater than 200 mg/L of chloride interferes with the color development. Trace concentrations of iodide are determined by its abiUty to cataly2e ceric ion reduction by arsenous acid. The reduction reaction is stopped at a specific time by the addition of ferrous ammonium sulfate. The ferrous ion is oxidi2ed to ferric ion, which then reacts with thiocyanate to produce a deep red complex. 

The demand for metallic arsenic is limited and thus arsenic is usually marketed in the form of the trioxide, referred to as white arsenic, arsenious oxide, arsenious acid anhydride, and also by the generally accepted misnomer arsenic. 

Arsenic Oxides and Acids. The only arsenic oxides of commercial importance are the trioxide and the pentoxide. These are readily soluble in alkaline solution, forming arsenites and arsenates, respectively. 

Arsenic acid (arsenic pentoxide hydrate, arsenic V oxide hydrate, orthoarsenic acid) [12044 50-7] M 229.8 + XH2O, pKj 2.26, pK 6.76, pKj 11.29 (H3ASO4). Cryst from cone solns of... 

Chemical Designations - Synonyms Arsenous Acid Arsenous Acid Anhydride Arsenous Oxide Arsenic Sesquioxide White Arsenic Chemical Formula AsjOj. 

Tlie use of As comjiounds as herbicides and pest controls in agriculture is now considerably restricted because of environmental considerations though arsenic acid itself. AsO(OH).v, is still used in die formulation of wood preservatives. The oxide is widely used to decolorize glass. 

Arsen-oxyd, n, arsenic oxide, specif, arsenic trioxide, arsemc(III) oxide. -pra parat, n, arsenical preparation, arsenical, -probe, /, arsenic test or sample, -rohr, n, -rShre, /. arsenic tube, -rotgultigerz, n. proustite. -rubin, m. realgar, -salz, n. arsenic salt, arsensauer, a. of or combined with arsenic acid, arsenate of,... 

Arsenic Pantoxide (Arsenic Acid Anhydride, Arsenic Oxide). As2Os, mw 229.84, white amorph powd, mp 315° (decompn), d 4.32g/cc. Sol in ale, acids, alkalies and w. Prepn is by heating a rnixt of As2 3 with coned HN03 (d 1.38g/cc) until the evoln of nitrogen oxides ceases. The soln of H3As04 is then evapd to dryness, redissolved in w and reevapd until a temp of over 300° is reached. It is used as a chemical reagent... 

Arsenic Trtoxide (Arsenous Acid, Arsenous Acid Anhydride, Arsenious Oxide, Arsenic Sesqui-oxide, White Arsenic). As203, mw 197.82 ... 

The presence of arsenous acid causes a considerable change in the induced reaction the error in the H2O2 determination decreases to a minimum and an As(ril) error appears, while the S2OI error remains practically unchanged. Though reaction between arsenic(III) and peroxydisulphate is about ten times as rapid as that between hydrogen peroxide and peroxydisulphate, the extent of the induced reduction of peroxydisulphate remains practically unchanged. This indicates that, in the induced chain oxidation, reaction (85), is replaced by the more rapid reaction... 

Drivers for Performing Arsenous Acid Oxidation in Micro Reactors... 

For arsenous acid oxidation, fundamental studies on the interplay of flow and reaction were made. By means of capillary-flow investigations, spatio-temporal concentration patterns were monitored which stem from the interaction of a specific complex reaction and transport of reaction species by molecular diffusion [68]. One prominent class of these patterns is propagating reaction fronts. By external electrical stimulus, electromigration of ionic species can be investigated. 

Beneficial Micro Reactor Properties for Arsenous Acid Oxidation... 

Arsenous Acid Oxidation Investigated in Micro Reactors Organic synthesis 92 [OS 92] Oxidation of arsenous acid by iodate... 

Figure 4.101 Formation of zones due to the change of reaction mechanism by applying an electrical field during the oxidation of arsenous acid by iodate ( = 2.0 V cm" ). Numbers show the time intervals after the electric field was switched on. Intermediate product iodine (dark) and iodide (white) [68. ...

Arsenous Acid Anhydride Arsenous Chloride Arsenous Hydride Arsenous Oxide Anhydride Arsenous Trichloride Arsenous Trioxide Arsenowodor Arsenwasserstoff... 

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