Study of ion-association complexes used in spectrophotometric determination of iron.
The following ion-association systems were investigated spectrophotometrically: Fe(2,2'-bipyridyl)(3)(Methyl Orange)(2); Fe(1,10-phenanthroline)(3)(Methyl Orange)(2); Fe(4,7-diphenyl-1,10-phenanthroline)(3)(Methyl Orange)2; Fe(1,10-phenanthroline)(3)(Benzyl Orange)2; Fe(4,7-diphenyl-1,10-phenanthroline)(3)(Benzyl Orange)(2). The molar absorptivities may be calculated with good precision on the basis of the spectra of the reacting species (iron chelate and dye anion), their stoichiometry and the degree of extraction. Analytically the most useful is the Fe(1,10-phenanthroline)(3)(Methyl Orange)(2) complex, molar absorptivity 4.83 x 10(4) 1. mole(-1) cm(-1) at 420 nm, but many metals (Co, Cu, Ni, Zn, Cd) form similar extractable complexes and interfere.
Hulanicki
A
A
Institute of Fundamental Problems in Chemistry University of Warsaw, Poland.
Nieniewska
J
J