ISSN:
0044-2313
Keywords:
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Colorimetrische Untersuchungen der Reaktion von Metavanadat (K3V3O9 bzw. (NH4)3V3O9) mit verschiedenen Säuren weisen auf das orange Hexavanadat-ion (HV6O17)3- als einziges Reaktionsprodukt hin, unabhängig von der Art der Säure (siehe Summary). Die Hydrolysenkonstantc des Ions (HV6O17)3- wurde zu 4,26 · 10-17 bestimmt. In bestimmten Bereichen läßt sich Vanadium auf Grund des orangefarbigen Hexavanadats colorimetrisch bestimmen.
Notes:
Colorimetric studies of the systems metavanadate-acid indicate the formation of the same hexacondensed orange vanadate ion (HV6O17)3-, independent of the nature and concentration of the reactants according to the following equation: \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{l} 2({\rm V}_{\rm 3} {\rm O}_{\rm 9})^{3 - } + 3{\rm HX = (HV}_{\rm 6} {\rm O}_{{\rm 17}})^{3 - } + 3{\rm X}^{\rm - } + {\rm H}_2 {\rm O,} \\ {\rm where X}^ - = {\rm ClO}_{\rm 4}^{\rm - },{\rm Cl}^{\rm - },{\rm F}^{\rm - },{\rm CH}_{\rm 3} {\rm COO}^{\rm - },{\rm ClCH}_{\rm 2} {\rm COO}^{\rm - } \\ \end{array}$$\end{document} Except the (HV6O17)3- ion, no indication of any other orange vanadate species could be found. The hexacondensed orange vanadate ion has been found to be the most coloured and highest polymerised species of all the vanadates. The hydrolytic dissociation constant for (HV6O17)3- ion has been found by JOB's method of continued variation to be 4.26 · 10-17. The tricondensation of metavanadate ion has been supported from the data obtained in the present work. The colour of orange vanadate has been found to approximately obey Beer's law in the concentration range 10-45 p. p. m. of vanadium.
Additional Material:
9 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/zaac.19603040509
