Silver chloride iodate

Tsunogai [7] carried out a similar coprecipitation allowing a 20-hour standing period to ensure that iodide is fully recovered in the silver chloride coprecipitate. Again, the iodide is oxidised to iodate prior to spectrophotometric determination of the latter. This procedure also includes a step designed to prevent interference by bromine compounds. 

Silver foil is transformed by an aq. soln. of the trichloride into silver chloride and iodide silver oxide with an excess of the trichloride is transformed into the chloride and iodic acid with more silver oxide, silver iodate is formed and with an excess of the oxide and a boiling soln. some silver periodate is formed. Mercuric oxide is slowly transformed into mercuric chloride and oxide chlorine, oxygen, and possibly chlorine monoxide are evolved. Aq. soln. of the trichloride give a precipitate of iodine with a little stannous chloride with more stannous chloride, some stannous iodide is formed. Consequently, although chloroform extracts no iodine from the aq. soln., it will do so after the addition of stannous chloride. Sulphur dioxide and ferrous sulphate are oxidized. 

Silicon, higher chlorides of, 42 Silicon tetrabromide, 38, 40 Silicon tetrachloride, 44 Silicopropane, octachloro, 44 Silicotungstic acid, 129 analysis, 131 ether complex, 131 Silver, metallic, 4 Silver chloride, reduction of, 3 Silver cyanamide, 98 Silver residues, purification of, 2 Sodium amalgam, 10 Sodium amide, 74 Sodium azide, purification of, 79 Sodium azidodithiocarbonate, 82 Sodium butoxide, 88 Sodium hypochlorite (solution), 90 Sodium iodate, 168 Sodium metaperiodate, 170 Sodium paraperiodate, chlorine method, 169 persulfate method, 170 Strontium amalgam, 11 Sulfur hexafluoride, 121 Sulfuryl chloride, 114... 

The rates of reaction of hypophosphorous acid with iodine bromine ", chlorine ", iodine chlorides , iodate , selenious and tel-lurous acids, silver nitrate , cupric chloride and mercuric chloride" (all forming phosphorous acid or phosphites) have been measured, and the results of the earlier work summarized clearly" . All the data are consistent with the hypothesis that there is prior transformation to some reactive form (I). This form (I) does not discriminate very effectively between different oxidants and thus the oxidation steps are presumed to have rates close to the diffusion-controlled limit. The rates of formation of I deduced in these studies are close enough to the rates of deuterium and tritium exchange for the residual difference to represent an isotope effect. Mitchell wrote the formula H5PO3 for I. Others have supposed it to be a tautomer e.g. HPO(OH)2. Both the isotopic exchange results and the oxidation studies require that its formation and decomposition be subject to acid catalysis. For the general mechanism... 

Potassium propionate Potassium propylparaben Potassium salicylate Potassium sorbate Potassium sulfite Propionic acid Propyl benzoate Propylparaben Quatemium-15 Salicylic acid Silver borosilicate Silver chloride Silver magnesium aluminum phosphate Sodium benzoate Sodium bisulfite Sodium butylparaben Sodium dehydroacetate Sodium ethylparaben Sodium formate Sodium hydroxymethylglycinate Sodium iodate Sodium metabisulfite Sodium methylparaben Sodium paraben Sodium o-phenylphenate... 

The familiar test for Cl ions through precipitation of silver chloride on the addition of nitric acid to the ammoniacal solution cannot be used in the presence of IO3- ions because the latter behave like Cl ions under these circumstances. However, a reliable differentiation is based on the finding that a solution of mercuric cyanide that has been acidified with sulfuric acid (or some other oxyinorganic acid) gives hydrogen cyanide when alkali chloride is present, whereas alkali iodate has no such effect. The hydrogen cyanide is volatile and readily detected. 

Silver diethyldithiocarbamate [1470-61-7] is a reagent commonly used for the spectrophotometric measurement of arsenic in aqueous samples (51) and for the analysis of antimony (52). Silver iodate is used in the determination of chloride in biological samples such as blood (53). 

Discussion. These anions are both determined as silver bromide, AgBr, by precipitation with silver nitrate solution in the presence of dilute nitric acid. With the bromate, initial reduction to the bromide is achieved by the procedures described for the chlorate (Section 11.56) and the iodate (Section 11.63). Silver bromide is less soluble in water than is the chloride. The solubility of the former is 0.11 mg L 1 at 21 °C as compared with 1.54 mg L 1 for the latter hence the procedure for the determination of bromide is practically the same as that for chloride. Protection from light is even more essential with the bromide than with the chloride because of its greater sensitivity (see Section 11.57). 

Matthews and Riley [99] preconcentrated iodide by co-precipitation with chloride ions. This is achieved by adding 0.23 g silver nitrate per 500 ml of seawater sample. Treatment of the precipitate with aqueous bromine and ultrasonic agitation promote recovery of iodide as iodate which is caused to react with excess iodide under acid conditions, yielding I3. This is determined either spectrophotometrically or by photometric titration with sodium thiosulfate. Photometric titration gave a recovery of 99.0 0.4% and a coefficient of variation of 0.4% compared with 98.5 0.6% and 0.8%, respectively, for the spectrophotometric procedure. 

Comparing the stability of the triammincs of silver halides, the chloride is more stable than the bromide, and the iodide cither does not exist or is very unstable. This is contrary to the usual observations in the ammines, where the stability of the ammine rises from chloride to iodide. In the case of the ammines of the oxy-halogen salts of silver the most unstable is the iodate, which is non-existent at ordinary pressure, then comes the bromate, and the most stable is the chlorate.3... 

Silicochloroform Silicolluoric Acid Silicon Chloride Silicone Fluids Silicon Tetrachloride Silver Acetate Silver Carbonate Silver Fluoride Silver Iodate Silver Monofluoride Silver Nitrate Silver Oxide Silver Sulfate Silvisar 510 Slaked Lime Slow-Curing Asphalt Sodamide Sodium... 

An iodate does not react with concentrated sulphuric acid in the cold or upon gentle heating. A solution of an iodate gives with silver nitrate solution a white precipitate of silver iodate, insoluble in m nitric acid but soluble in dilute ammonia solution, thus simulating the behaviour of a chloride towards these reagents. Iodates, however, give a white precipitate of barium iodate, Ba(I03)2, with barium chloride solution the precipitate is sparingly soluble in dilute nitric acid. 

Test for periodate (see note 1 below) This anion will give a positive test for oxidizing agents, but will not be detected in the systematic analysis. It will be necessary to remove first iodide or iodate by precipitation with silver nitrate in acid solution, and the excess silver ions with sodium chloride solution the resulting solution is strongly acidified with hydrochloric acid and an iron(II) salt is added. If a periodate is present, it will be reduced to iodine, which can be identified with carbon tetrachloride. 

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