Accession Number:

AD0255479

Title:

COPPER AS A PHOTOMETRIC INDICATOR IN THE SELECTIVE CHELOMETRIC TITRATION OF METAL ION MIXTURES

Descriptive Note:

Corporate Author:

NORTH CAROLINA UNIV CHAPEL HILL

Personal Author(s):

Report Date:

1961-03-02

Pagination or Media Count:

1.0

Abstract:

Photometric and point detection permits selective chelometric determination of metal ions in mixtures with much less masking than required for visual or potentiometric techniques. Copper has been found to be a useful photometric indicator for such titrations. Prediction of appropriate titration conditions is readily accomplished with graphical plots of effective chelonate stability. Calcium is determined in the presence of magnesium with ethylene glycol bisbeta-aminoethyl ether-N,N-tetraacetic acid in 0.5 M ammonium hydroxide at pH 10. Selective determination of cadmium or of zinc in the presence of the other is carried out with diethylenetriaminepentaacetic acid under the same conditions. Attention is directed to the importance of competitive equilibria which affect chelonate stability, and stability constants for ammonia derivatives of some copper chelonates are reported. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE