Synthesis and ion-exchange properties of thermally stable stannic selenite

Stannic selenites have been synthesized under a variety of conditions. The most stable sample is prepared by mixing 0-0.5M solutions of stannic chloride and sodium selenite in the ratio of 1:1 at pH 1. It is a bifunctional amorphous material. A tentative structure has been proposed on the basis of chemical composition, pH titrations, infrared and thermogravimetric analyses. Its ion-exchange capacity is 0.75 and 0.73 meq g after drying at 50 degrees and 500 degrees respectively. Its analytical importance has been established by the following quantitative separations: Cu(2+) from Ni(2+), Co(2+), Fe(3+), Ga(3+) and In(3+), Fe(3+) from Pb(2+) and Sc(3+), and Sc(3+) from VO(2+).     

Systematic analysis for common cations by solid-state spot-tests

Solid-state capillary spot-tests for 17 cations with 16 organic and inorganic reagents have been examined. A comparative study of the colour reactions in solution has also been made. Some new reactions are described. The reactions studied have been systematized.     

Radiochemical separation of antimony by isotopic exchange

Isotopic exchange has been used to develop a simple and rapid procedure for radiochemical separation of antimony. A number of variables which affect the yield were studied and optimised, and antimony yields of 96% were obtained at 30 degrees . Acids and alkalies decrease this yield considerably because they dissolve part of the precipitate. The mode of preparation of the antimony oxide precipitate and the temperature also affect the isotopic exchange. Studies made with radioactive tracers of 14 different elements show contamination of < 1% for most elements. The high contamination with (95)Zr-(95)Nb can be reduced considerably by adding carrier. The simple procedure can be carried out in about 13 min and does not require any special equipment.     

Adsorption of cations from formic acid solutions on strong acid cation-exchange resin. Separation of zirconium from thorium and from gallium

The adsorption of Pb(II), Cu(II), Bi(III), Cd(II), Mn(II), Co(II), Ga(III), Y(III), Zr(IV) and Th(IV) from aqueous solutions of formic acid on cation-exchanger Dowex 50W-X8 has been studied. Electrophoretic measurements have also been made. Possible separations are suggested and discussed. Zirconium may be quantitatively separated from thorium and from gallium.     

Effect of dielectric constant on Rf values of metal ions in some formic acid-alcohol solvent systems

Correlations between dielectric constant and R(f) values for numerous alcohol-formic acid systems have been made. Most metal ions behave similarly, but arsenic(III), antimony(III) and tin(II) show different properties.     

3, 6-pyridazinediol as a specific spectrophotometric reagent for the determination of iron

Iron(III) reacts with 3,6-pyridazinediol in presence of nitric acid to give pink color having maxima at 480 mμ. The color reaction which is specific for iron(III), has 1 μg/ml as visual limit of identification and provides the basis of a new spectrophotometric method for the determination of iron. The quantitative assessment of the tolerable amount of different ions which do not interfere with the determination are reported. The mechanism of the color reaction is not clear.     

A general method for the spectrophotometric determination of aromatic aldehydes

Summary Aromatic aldehydes and some of their binary mixtures can be determined spectrophotometrically with diphenylamine in the presence of hydrochloric acid. Errors are in the range of 6–10%. Various other organic compounds do not interfere.

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Allgemeines Verfahren zur spektralphotometrischen Bestimmung aromatischer Aldehyde

Zusammenfassung Aromatische Aldehyde und einige ihrer binären Gemische können mit Diphenylamin in salzsaurer Lösung spektralphotometrisch bestimmt werden. Fehler sind im Bereich von 6–10%. Eine große Zahl anderer organischer Verbindungen stört nicht.