The complexes of diphenylcarbazone with zinc, nickel and cobalt are studied spectrophoto-The wavelength of maximal absorbanmetrically in a 50 volume percent aqueous acetone medium. ce is situated between 520-525 nm. independently from the method of continuous variation and the slope-ratio method. In such a case the slope-ratio method is much more useful.-845 -
FIG. I Continuous variation curves for the systems-[Ll0 -6 x 10-4M. TL + TM -2.4 x 10-4M) .The change in absorbance was examined as a function of DPCO concentration with a constant The variation in absorbance was also measured as a function of increasing metal-ion content with a constant ( 2 x 10-5M) DPCO concentration.