Titanous sulphate

The detection and determination ot the perchlorates.—The perchlorates give no precipitates with silver nitrate or barium chloride soln. cone. soln. give a white crystalline precipitate with potassium chloride. Unlike all the other oxy-acids of chlorine, a soln. of indigo is not decolorized by perchloric acid, even after the addition of hydrochloric acid and they do not give the explosive chlorine dioxide when warmed with sulphuric acid unlike the chlorates, the perchlorates are not reduced by the copper-zinc couple, or sulphur dioxide. Perchloric acid can be titrated with —iV-alkali, using phenolphthalein as indicator. The perchlorates can be converted into chlorides by heat and the chlorides determined volumetrically or gravimetrically they can be reduced to chloride by titanous sulphate 28 and titration of the excess of titanous sulphate with standard permanganate they can be fused with zinc chloride and the amount of chlorine liberated can be measured in terms of the iodine set free from a soln. of potassium iodide and they can be... 

Titanous sulphate (p. 503) may be similarly employed. (J. S. C. I., 41, 158.) It has the advantage of not giving rise to halogenated compounds as are given by titanous chloride in some instances. 

Titanous chloride comes on the market in the form of a 20% solution (see p. 485). Usual impurities oxidation products. For the many reducing reactions in which titanous chloride is used it may be replaced by titanous sulphate (obtainable as 20% solution), which should be used when there is possibility of chlorination. 

On stirring a mixture of a few cubic centimetres of a solution of titanous sulphate and one litre of a 0-01 per cent, solution of cupric sulphate, metallic copper separates after an interval of a few minutes. Most of the finely divided metal passes through a filter-paper, the colour of the solution being blue by transmitted light, and copper-red by reflected light. The reaction affords a sensitive test for copper, since by its aid one part of the metal can be detected in one million parts of solution.3... 

Potassium perchlorate may be detected in mixtures by the methylene blue reaction (see under Potassium Chlorate). It may be estimated quantitatively by heating, as described under Potassium Nitrate, or by nitron also by precipitation as methylene blue perchlorate and titration of the excess of methylene blue with picric acid. It can also be reduced with titanous sulphate or chloride. 

What hydrates are called alpha- and beta-titanic acids, how are they prepared, and what are their properties How, having at hand titanium(IV) oxiue, can you prepare potassium titanate and titanyl sulphate ... 

Oxidation processes involving the subsequent titration of an excess of ferrous sulphate,2 oxalic acid (in the presence of silver sulphate as catalyst), titanous chloride,4 or of the quantity of iodine liberated from potassium iodide,5 are also available but are less satisfactory. In the last-named method a large excess of potassium iodide is necessary to obtain complete reaction in a short time. The reaction may be accelerated by the addition of potassium chloride6 or ammonium chloride with 20 per cent, by weight of the latter salt present a large excess of the iodide is not necessary and the liberated iodine may be titrated after fifteen minutes.7... 

Reduction with titanous chloride and sulphate ia alao... 

This method is suitable for almost all azo dyes and some other water-soluble dyes. The titration should be conducted in a well-ventilated fume hood. A dye sample is dissolved in a hydrochloric acid solution. An excess amount of titanous chloride solution is added into the boiling acidic dye solution under the protection of a CO, atmosphere. A back titration is then conducted using a standardised ferrous ammonium sulphate solution with ammonium thiocyanate as the indicator. The titanous chloride solution should be freshly standardised. 

Barium Stannate. BaSn03 it is sometimes added to barium titanate bodies to decrease the Curie temperature. An electroceramic containing approx. 90 mol% BaTi03 10 mol%, BaSn03 has a very high dielectric constant (8000-12000 at 20°C). Barium Sulphate. BaSO m.p. 1580°C sp. gr. 4.45. 

Cadmium Yellow. Cadmium sulphide, coprecipitated with barium sulphate. Cadmium Zirconate. CdZr03 occasionally used as an addition to barium titanate bodies, the effect being to reduce the dielectric constant and Curie temperature. 

The order of presentation of the uranium minerals will follow chemical groups. The U minerals are discussed first, followed by the niobates, tantalates and titanates. These two groups include the primary reduced minerals. The uranyl minerals are considered in the order hydrated oxides, silicates, phosphates and arsenates, vanadates, molybdates, sulphates, carbonates, and selenates and tellurates. Each section includes an evaluation of the known crystal chemistry and its effect on chemical variability and occurrence of mineral species. 

Translational disorder [86/7] fluorides [86/26] CuGe03 [96/C7] clays [99/40] chlorocadmate, thiourea sulphate, zirconate-titanate [96/12]... 

A method of assay, applicable to most medicinal dyestuffs, depends upon their reduction with titanous chloride. The procedure has to be modified in detail for dissolving the dyestuff and for some dyes the endpoint is not indicated by a sharp decolorisation and an excess of titrant must be added, the excess being back titrated with ferric ammonium sulphate. 

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