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Sulfuric acid , primary standard solutions

Suppose a sulfuric acid solution, rather than the hydrochloric acid solution in question 22, is standardized with primary standard THAM. Does the calculation change in any way Explain. [Pg.96]

Colorimetric solutions are used in the preparation of colorimetric standards for certain chemicals and for the carbonization tests with sulfuric acid that are specified in several monographs. Directions for the preparation of the primary colorimetric solutions and Matching Fluids are given under the test for Readily Carbonizable Substances, Appendix IIB. Store the solutions in suitably resistant, tight containers. [Pg.962]

Sodium oxalate has been used as a primary standard substance for Ce(IV) in sulfuric acid. In the absence of a catalyst a temperature of 70 to 75°C is necessary. Smith and Getz found that in 1 to 2 M perchloric acid solution, sodium oxalate can be titrated at room temperature with Ce(IV) perchlorate or nitrate but not with sulfate. Rao, Rao, and Rao carried out the titration at room temperature in the presence of barium chloride to remove sulfate, which retards the reaction between oxalate and Ce(IV) and between oxalate and oxidized ferroin. Alternatively, some Fe(III) was added, and the trace of Fe(II) produced photochemically then reacted with the indicator. Rao, Rao, and Murty carried out the titration in 0.5 M HNOj with ammonium hexanitratocerate(IV) instead of the sulfate. With a small amount of KI and KIO3, a satisfactory end point was obtained at room temperature with ferroin as indicator. [Pg.340]

Dosimetry is the measurement of absorbed dose. The unit of absorbed dose is the gray (Gy). Because dose is a measure of absorbed energy, calorime-try is the fundamental method of measurement. However, calorimetry suffers from being insensitive, complex, slow and highly demanding in technical skills and experience. Primary dose measurement is usually done with substances that are chemically changed quantitatively in response to the amount of radiation absorbed. For most purposes the standard primary system is the Fricke or ferrous sulfate dosimeter. In this system, which consists of a solution of ferrous sulfate in dilute sulfuric acid, ferrous ions Fe are oxidized by absorbtion of radiation to ferric ions Fricke dosimeters are usually presented in glass... [Pg.74]

A number of solutions when freshly prepared are used as alternative primary standards, for example sodium and potassium hydroxides, sulfuric and hydrochloric acids, and potassium manganate(vii). These cannot be stored since their concentrations change with time due to a chemical reaction (usually with oxygen and/or water in the storage vessel). [Pg.47]

Halates are readily prepared by the base hydrolysis of the halogen. Bromates and iodates can also be synthesized by the oxidation of the halide. Only iodic acid can be isolated outside of aqueous solution. Chlorates are excellent oxidizing agents, lodate occurs naturally, is a source of elemental iodine, and is a primary standard for iodimetry. The perhalic acids of chlorine and iodine are much easier to prepare than that of bromine. Perchloric acid, like sulfuric and phosphoric acid in previous groups, has a tetrahedral structure around the central atom and involves dir-pir... [Pg.559]

Of all pure chemicals water must surely be considered the essence of terrestrial life. Of Empedocles s original four elements it is the only one which we would still recognize as being a single pure discrete species, although of course, at the molecular level rather than at the atomic. Water is not only essential to biochemical processes, but is of primary importance to industrial and economic chemistry. There is thus some practical justification for the habitual aquocentricity of classical solution chemistry which chooses high dilution in water as the standard state for most studies. The economic importance of sulfuric and hydrochloric acids as heavy... [Pg.85]


See other pages where Sulfuric acid , primary standard solutions is mentioned: [Pg.338]    [Pg.153]    [Pg.296]    [Pg.351]    [Pg.434]    [Pg.970]    [Pg.971]    [Pg.973]    [Pg.567]    [Pg.574]    [Pg.430]    [Pg.73]    [Pg.398]    [Pg.839]    [Pg.141]    [Pg.397]    [Pg.287]    [Pg.72]   
See also in sourсe #XX -- [ Pg.137 ]




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Sulfuric acid , primary standard

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