Abstract
Binary and ternary mixtures of the organic compounds of the title elements are decomposed either by wet digestion in the Kjeldahl flasks or through combustion in the oxygen flask using 1:1 HNO3 soln. as absorbent and Pt gauze as sample holder. An aliquot of 15 μl of each decomposed mixture is separated on thin layer plate, using silica gel (G 60) as stationary phase and a mixture of 100 ml benzene: 80 ml acetone : 20 ml DMF as a mobile phase in normal saturation system at 25°C. The spots areas are determined, from which the individual concentrations of the cations are calculated. Parallely the spots are scratched from the plates and are eluted with water. Their concentrations are measured in the UV-region, for Hg(II) at 205 nm, for Cu(II) at 203 and for Cd at 201 nm. Concentrations are obtained from previously constructed calibration curves which are linear for Hg(II) in the range 0.0 – 0.375 ppm, for Cu(II) in the range 0.0 – 3.811 ppm and for Cd from 0.7 – 13.48 ppm.