A. K. Majumdar, G. Das
1966
Citations
0
Influential Citations
17
Citations
Journal
Analytica Chimica Acta
Abstract
Abstract A comparative study is described of the use of N-benzoyi- o -tolyl-, N-benzoyl- m -tolyl, N-benzoyl- p -tolyl-, N-benzoyl- p -chlorophenyl- and N-phenylacetylphenyl-hydroxylamines, as spectrophotometric reagents for the determination of vanadium, after extraction with chloroform. All the reagents form 1:2 (metal:reagent) complexes in hydrochloric acid media or at pH 4.8–6.0; the dissociation constants of the complexes are of the order of 10 -9 and 10 -8 , respectively, except those of N-benzoyl- p -chloro-phenylhydroxylamine which are of the order of 10 -8 in both media. The reactions in hydrochloric acid media are more selective and sensitive than those at pH 4.8–6.0. In presence of alcohol, the wavelengths of maximum absorption decrease. The p K a values of the hydroxylamines were determined in water and in alcohol-water (1:1) solutions.