Ferrous chlorate

Ferrous chlorate, Fe(C103)2, is probably formed in solution when ferrous sulphate and barium chlorate solutions are allowed to react. It is very unstable, however.15... 

Ferrous Sulfdte Titration. For deterrnination of nitric acid in mixed acid or for nitrates that are free from interferences, ferrous sulfate titration, the nitrometer method, and Devarda s method give excellent results. The deterrnination of nitric acid and nitrates in mixed acid is based on the oxidation of ferrous sulfate [7720-78-7] by nitric acid and may be subject to interference by other materials that reduce nitric acid or oxidize ferrous sulfate. Small amounts of sodium chloride, potassium bromide, or potassium iodide may be tolerated without serious interference, as can nitrous acid up to 50% of the total amount of nitric acid present. Strong oxidizing agents, eg, chlorates, iodates, and bromates, interfere by oxidizing the standardized ferrous sulfate. 

Reagents similai to those used in the analysis of chloiine are commonly employed in the quantitation of gaseous and aqueous chloiine dioxide as well as its reaction coproducts chlorine, chlorite, and chlorate. The volatihty of the gas from aqueous solutions as well as its reactivity to light must be considered for accurate analysis. Other interferences that must be taken into account include other oxidizers such as chloramine, hydrogen peroxide, permanganate, and metal impurities such as ferrous and ferric iron. 

Chlorate Analysis. Chlorate ion concentration is determined by reaction with a reducing agent. Ferrous sulfate is preferred for quaHty control (111), but other reagents, such as arsenious acid, stannous chloride, and potassium iodide, have also been used (112). When ferrous sulfate is used, a measured excess of the reagent is added to a strong hydrochloric acid solution of the chlorate for reduction, after which the excess ferrous sulfate is titrated with an oxidant, usually potassium permanganate or potassium dichromate. 

Elemental composition K 28.22%, Cl 25.59%, and 0 46.19%. An aqueous solution is analyzed for potassium by AA, ICP, and other methods (see Potassium). Perchlorate ion may be analyzed by ion chromatography or a liquid-membrane electrode. Iodide, bromide, chlorate, and cyanide ions interfere in the electrode measurement. Alternatively, perchlorate ion may be measured by redox titration. Its solution in 0.5M H2SO4 is treated with a measured excess standard ferrous ammonium sulfate. The excess iron(II) solution is immediately titrated with a standard solution of potassium dichromate. Diphenylamine sulfuric acid may be used as an indicator to detect the end point ... 

With the loss of labour and the increased intensity of farming, it became increasingly difficult to control weeds on farms and so the search began for chemicals that could be used selectively. The first examples included compounds such as copper sulfate (introduced in France in 1896 and in Britain in 1898) and were used to control weeds in cereals.1 This was followed from 1901 to 1919 with compounds such as ferrous sulfate, sulfuric acid and sodium chlorate. The principle that applied in the case of these compounds was that the cereal was less easy to wet than... 

Chlorates are reduced to a lower state of oxidation by sulphurous acid, and the soln. then decolorizes indigo while chloric acid does not decolorize this reagent, bromic acid does. Ferrous salts in the presence of dil. sulphuric acid quickly reduce chlorates, but not perchlorates, to chloride KC103+3HoS04+6FeSC>4 =3Fe2(S04)8+3H20+KCl. 

Estimation of Selenium in Sulphide Minerals.s—In various sulphite-cellulose manufactories difficulties have occurred which have been traced to the presence of selenium in the pyrites used for burning. Part of the selenium remains in the burnt pyrites and part volatilises with the sulphur dioxide. 20 to 30 grams of pyrites are dissolved in hydrochloric acid (dens.=1-19) and potassium chlorate. Zinc is added to reduce the iron to the ferrous condition more hydrochloric acid is then added, the solution boiled and stannous chloride added to precipitate selenium. Since the selenium may contain arsenic, it is collected on an asbestos filter, dissolved in potassium cyanide and reprecipitated using hydrogen chloride and sulphur dioxide. The element may then be estimated by the iodometric method described below. In order to determine the relative proportion of volatile to non-volatile selenium, the pyrites may be roasted in a current of oxygen. After this treatment the contents of the tube are dissolved in warm potassium cyanide and the selenium reprecipitated and estimated in the ordinary way. 

Ferrous sulfate [CHLORINE OXYGEN ACIDS AND SALTS - CHLORIC ACID AND CHLORATES] (Vol 5) [COLORANTS FORFOOD, DRUGS, COSMETICS AND MEDICAL DEVICES] (Vol 6) [COLORANTS FORFOOD,DRUGS, COSMETICS AND MEDICALDEVICES] (Vol 6) [ELECTROLESS PLATING] (Vol 9) [FEEDS AND FEED ADDITIVES - PETFOODS] (Vol 10)... 

These pigments are manufactured by treating ferrous sulfate (FeS04) solutions (sometimes in the presence of ammonium sulfate) with sodium ferrocyanide, giving a white ferrous ferrocyanide, which is then oxidized to ferric ferrocyanide, Fe4[Fe(CN)6], or to Fe(NH4)[Tc(CN)6 by different reagents such as potassium chlorate, bleaching powder, and potassium dichromate. The colloidal pigment is washed and allowed to settle to enhance separation, since filtration of the colloidal solid is difficult. 

In order to make the walls of the iron pot passive a small amount of alkali chlorate (some 20 kg per 8 000 kg of caustic) is added to the melt. The iron which in spite of this measure dissolves in the caustic in the form of sodium ferrate Fe(ONa)s, is reduced by an admixture of sulphur to give ferrous sulphide which is separated by settling together with other impurities, especially sodium car-bonate. The melt is left standing and cooled to 350 °C. It is then siphoned or pumped by an immersion pump directly to iron drums where it solidifies. Flaked hydroxide can be also obtained if a water cooled rotating drum is dipped into the melt. A thin film of hydroxide will adhere to the rotating drum. The film solidifies and is scraped off with a thin knife. (See Fig. 108.)... 

Iron blues, or cyanide iron blues, are complex ferriferrocyanide, generally with ammonium, potassium, or sodium cations. They are most commonly produced by a two-step process. First, ammonium, potassium, or sodium ferrocyanide, M4[Fe(CN)6], is reacted with ferrous sulfate, FeS04, to yield M2Fe[Fe(CN)]6. The latter is digested with hot sulfuric acid and oxidized with sodium chlorate or sodium bichromate to yield the ferric ferrocyanide M(Fe[Fe(CN)6]. ... 

The ferrous ion is traditionally re-oxidized with manganese dioxide or sodium chlorate, but Caro s acid has also been introduced for this application.263 Under these conditions, Caro s acid is more efficient than hydrogen peroxide. 

Ferrous thio-pyrophosphite, Fe2P2Sc, has been obtained 1 by heating a mixture of sulphur and red phosphorus with excess of iron wire to redness and maintaining at this temperature for several hours. It yields greyish black hexagonal plates which appear brown by transmitted light. They are attacked by nitric acid, but more easily by this acid containing a little potassium chlorate. 

Bromine attacks it at red heat with incandescence chlorine is less vigorous in its action, whilst iodine and hydrogen iodide have no action, even at 1100° C. The chlorate and nitrate of potassium do not affect it at their melting-points, but at higher temperatures decompose it with incandescence. Fused alkali hydroxides and carbonates decompose it rapidly. Concentrated sulphuric acid is without action in the cold, but with the boiling acid ferrous sulphate is produced. Dilute nitric acid dissolves it when hot, and the concentrated acid acts vigorously. Dilute hydrochloric acid is without action, and the hot concentrated acid acts only slowly. 

To determine the total iron content, the solution is first oxidised with potassium chlorate, and the ferric iron solution thus obtained titrated as above. The difference between two such determinations gives the amount of ferrous iron. 

Iron and Chlorine—Ferrous Chloride—Ferrochlorides—Ferric Chloride—Tetra-chlorferrates — Pentachlorferrates — Hexachlorferrates — Miscellaneous Double Salts—Chlorates, Perchlorates and Oxychlorides of Iron. 

Experiment 192. — (a) To a solution of fresh or freshly washed ferrous sulphate add a little hydrochloric acid, warm gently, and then add a few crystals of potassium chlorate. After heating a short time, test portions of the liquid for a ferric and a ferrous compound. 

For the case of three different molecules we have the experiments of Noyes and Wason on the reaction between ferrous chloride, potassium chlorate, and hydrochloric acid, studied by Hood Here we have to do with the equation... 

Example L If potassium chlorate, KClOg, is dissolved in water dn,d o solution of ferrous salt, such as ferrous sulfate, FeS04, containing some sulfuric acid is added the chlorate ion is reduced to chloride ion and the ferrous ion is oxidized to ferric ion. Write the equation for liic reaction. 

Write electrode equations for the electrolytic production of (a) ferric ion from ferrous ion (b) magnesium metal frtmi molten magnesium chloride (c) perchlorate ion, CIO4—, from chlorate ion, CIOg, in aqueous solution ... 

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