A Highly Selective Spectrophotometric Determination of Niobium (V) Using 3-Hydroxy-2-[1'-Phenyl-3'-(p-Chlorophenyl)-4′-Pyrazolyl]-4-Oxo-4H-1-Benzopyran as a Complexing Agent
| Autor: | N. Agnihotri, Raj Kamal, J. R. Mehta |
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| Rok vydání: | 2006 |
| Předmět: |
Flavonoids
Perchlorates Time Factors Chloroform Niobium Inorganic chemistry chemistry.chemical_element Molar absorptivity Sensitivity and Specificity Absorption Analytical Chemistry Benzopyran Absorbance chemistry.chemical_compound chemistry Spectrophotometry Reagent Environmental Pollutants Chelation Perchloric acid General Environmental Science Nuclear chemistry |
| Zdroj: | Annali di Chimica. 96:479-485 |
| ISSN: | 1612-8877 0003-4592 |
| DOI: | 10.1002/adic.200690048 |
| Popis: | 3-Hydroxy-2-[1'-phenyl-3'-(p-chlorophenyl)-4'-pyrazolyl]-4-oxo-4H-1benzopyran (HPCPB) is used as an analytical reagent for the spectrophotometric determination of niobium in trace amounts with which it forms a yellow coloured complex (4:1) in perchloric acid medium. The complex is extractable into chloroform and shows absorption maximum at 407-418 nm with a molar absorptivity of 2.79 x 10(4) L mol(-1) cm(-1) and Sandell's sensitivity equal to 0.0033 microg Nb(V) cm(-2), respectively. Beer's law holds good in the range 0-1.2 microg Nb ml(-1), with a standard deviation of +/- 0.0015 absorbance units. The method is free from the interference of a large number of elements and handles satisfactorily the analysis of various samples of varying complexity. |
| Databáze: | OpenAIRE |
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