Iodates and periodates

The removal of inorganic salts from reaction mixtures afforded by polymeric materials may be simply and effectively accomplished by dialysis,166 178 after decomposition of remaining periodate with ethylene glycol130 131 or butylene glycol. 161 170 Alternatively, the iodate and periodate ions may be removed as such, or after reduction to free iodine. The iodate and periodate ions have been effectively precipitated by means of sodium carbonate plus manganous sulfate,6 or by lead dithionate,191 barium chloride,24 192 193 strontium hydroxide194 202 or barium hydroxide,203 204 lead... 

Iodide is oxidised to iodate or periodate in the membrane cell during the electrolysis process. Iodide, iodate and periodate are therefore present in the brine of a membrane electrolyser. Figure 12.5 shows comparative plots of laboratory adsorption test data for the removal of iodide and other relevant species. 

Tetrafluoroammonium hexafluoromanganate, 4378 Tetrafluoroammonium hexafluoronickelate, 4379 Tetrafluoroammonium hexafluoroxenate, 4380 Tetranitromethane, 0543 Titanium tetraperchlorate, 4164 1,1,1 -Triacetoxy-1,2-benziodoxol-3-one, 3604 Trifluoromethyl hypofluorite, 0352 Trimethylsilyl chlorochromate, 1297 Trioxygen difluoride , 4317 Uranium hexafluoride, 4369 Vanadium trinitrate oxide, 4758 Vanadium(V) oxide, 4860 Vanadyl perchlorate, 4146 Xenon hexafluoride, 4371 Xenon tetrafluoride, 4347 Xenon tetrafluoride oxide, 4340 Xenon tetraoxide, 4857 Xenon trioxide, 4851 Xenon(II) pentafluoroorthoselenate, 4376 Xenon(II) pentafluoroorthotellurate, 4377 Zinc permanganate, 4705 ACETYLENIC PEROXIDES ACYL HYPOHALITES ALKYL HYDROPEROXIDES ALKYL TRIALKYLLEAD PEROXIDES AMINIUM IODATES AND PERIODATES AMMINECHROMIUM PEROXOCOMPLEXES BIS (FLUOROOXY)PERHALOALKANES BLEACHING POWDER CHLORITE SALTS... 

Aminium iodates and periodates, 36 Aminium nitrates, 36 Aminium perchlorates, 36 Aminomethoxy compounds, 36 Amminechromium peroxocomplexes, 37 Amminemetal azides, 37 Amminemetal halides, 38 Amminemetal nitrates, 38 Amminemetal oxosalts, 38 Annulenes, 43 Aprotic solvents, 43 Aqua regia, 43... 

Concentrated HCI Manganese (II) sulfate + phosphoric acid Chlorine dioxide gas evolved, imparts yellow color to acid Violet coloration due to diphosphatomanganate formation peroxydisulfate nitrates, bromates, iodates, and periodates react similarly... 

Several iodates and periodates of both Hg(I) and Hg(II) have been known for a long time. The older literature is summarized by Gmelin59 and Mellor.60 However, for more than 60 years very little work has been done on these compounds. No thermodynamic data are listed by Wagman et al.1 A brief summary relating to thermal decomposition is given below. 

Potassium iodide m aqueous solution is oxidised to free iodine, the reaction having been extensively applied in the early historv of ozone, but it has now somewhat lost in favour because a similar effect can be produced by nitrogen peroxide or chlorine.3 If the action of the ozone is prolonged, the oxidation may proceed further to the formation of hypoiodite, iodate, and periodate.3... 

Hydrothermal Synthesis. Hydrothermal synthesis and reactive fluxes have been increasingly used as a method for synthetic actinide chemistry. Unique phases of actinide selenites, tellurites, iodates and periodates have all been synthesized under hydrothermal reaction conditions. New compounds and phases of oxyfluorides, phosphates, and sulfates using organic templates also have been synthesized with hydrothermal methods. " ... 

The use of iodate and periodic acid as oxidizers for noble metal CMP has also been attempted. Similar to W CMP, a surface oxidation or modification is required for the subsequent removal by mechanical force. For example, the potential use of ruthenium as bottom electrode capacitor for next-generation DRAM devices [40] has been explored. Owing to the fact that a dry-etch process can lead to the formation of toxic RUO4 [41], the possibility of using CMP to implement Ru has gained interest recently. The studies in this area have indicated that the formation of stable passive layers such as RUO2 [41,42] and RU2O5 [42] are important steps in the Ru CMP. 

The oxidations usually are carried out at room temperature with an excess of periodic acid or its salts. The analyses can be completed by several means. The lUPAC procedure for glycerol involves an alkalimetric titration of the formic acid generated, using a pH of 8.0 at the end point. More commonly, the excess periodate is determined by adding a slight excess of standard As(III) to reduce periodate to iodate then the excess As(III) is titrated with standard iodine. Both iodate and periodate can be determined by first masking the periodate with molybdate while iodate is titrated and then demasking the periodate with oxalate, followed by titration of the periodate. ... 

ACETYLENIC PEROXIDES, ACYL HYPOHALITES ALKYL HYDROPEROXIDES, ALKYL TRIALKYLLEAD PEROXIDES AMINIUM IODATES AND PERIODATES. AMMINECHROMIUM PEROXOCOMPLEXES... 

AMINIUM IODATES AND PERIODATES, AMINIUM PERCHLORATES DIAZONIUM PERCHLORATES, DICHROMATE SALTS OE NITROGENOUS BASES I-(I,3-DISELENONYLIDENE)PIPERIDINIUM PERCHLORATES... 

Iodine (I, at. mass 126.90) is a solid non-metal, which is fairly volatile at room temperature and sublimes easily. Iodine dissolves readily in aqueous KI solutions to yield the I,f complex, and is also soluble in organic solvents (CHCI3, CCI4, C6H6). It occurs mainly in the -I, V, and VII oxidation states. Iodide reveals reducing properties, whereas iodine, iodate, and periodate have oxidizing properties. Iodide, like chloride and bromide, forms sparingly soluble compounds and soluble complexes with some metals... 

Note that catechols (1,2-dihyroxybenzenes) are readily oxidized to o-quinones, l5 but the products are often sensitive to the electrophilic or nucleophilic species in the reaction medium. Catechol itself gives 125. Dimerization is as much a problem with catechols as with monophenols (see Table 3.4). The conversion of catechol to 125 used silver carbonate and it is noted that silver salts are the classical oxidation reagent for such transformations. Other reagent have been used to oxidize catechol derivatives, including ceric sulfate, lead tetraacetate, DDQ (2,3-dichloro-5,6-dicyano-l,4-benzoquinone), iodate, and periodate. ... 

The anions that furnish the oxygen for the pyrochemical action are nitrate, perchlorate, iodate, and periodate, and—exceptionally— chlorate, nitrite, and permanganate. 

Bromates, iodates, and periodates have hardly attracted the attention of the pyrochemist, though they could be of considerable theoretical interest. Bromates and iodates would be expected to be more stable than chlorates, and the few data that are available for the iodates point in this direction. 

The most widely applied method for the transformation of the polyaldehydes furnished by the above oxidation process, is the Smith-degradation involving successive oxidation with periodate in aqueous medium, removal of the iodate and periodate ions and subsequent reduction with sodium borohydride. The resulting polyalcohol is then hydrolyzed and the products in the hydrolysate are analyzed. Of the polysaccharides amylopectin (4) and cellulose (5) have been first analyzed by this method as demonstration of the usefulness of the procedure which has emerged recently as a generally employed way of analysis of polysaccharides. 

Voltammetric/polarographic methods are not very important for anion analysis. Only bromate, iodate, and periodate can be determined by means of polarographic reduction currents. Indirect determinations are possible for those anions that form compounds of low solubility or stable complexes with the Hg ions formed in the anodic oxidation of the electrode mercury. The current caused by the dissolution of the mercury is proportional to the concentration of these anions in the sample... 

With chlorites, nickel hydroxide forms black oxides of 3- or 4- valent Ni. The test is valid in the presence of chlorates, perchlorates, bromates, iodates and periodates. ... 

In acid solution, alkali iodate and periodate react with alkali iodide to yield iodine. 

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