Low-dentate reagents as titrants in complexometry: selection of promising reagents

An approach was proposed to the selection of promising titrants using computer databases. The approach takes into account the absolute and relative stabilities of complexes formed in the titration and also the competing protolysis reactions. Thirty-two low-dentate reagents were selected for determining five metals, inclusive of Cu, Cd, Fe, Pb, Hg. Under certain conditions, these reactions give clear jumps in logarithmic titration curves. With the selected reagents, potentiometric procedures equally precise and more selective than the procedures using EDTA were obtained