Kinetic microdetermination of manganese in natural waters and of osmium and ethylenediaminetetraacetic acid

Abstract

Automatic spectrophotometric kinetic methods are described for the microdetermination of manganese and osmium, based on their catalytic effect on the periodate—acetylacetone reaction, and for the determination of EDTA, on the basis of its inhibitory effect on the manganese-catalyzed periodate—acetylacetone reaction; the time required for the formation of a small fixed amount of colored product is measured automatically and related directly to the catalyst or inhibitor concentration. Manganese at the 10 -5–10 -7 M level, and osmium and EDTA at the 10 -7–10 -6 M level, can be determined with an average error of ca. 2%. The method has been applied to the determination of manganese in natural waters, but is capable of more general applications.