Bibliography: p. 92-97. / A review of the Literature reveals that the concentration of trace metals in natural water samples can be radically altered by adsorption/contamination phenomena within the storage vessel, and that container pre-cleaning and sample acidification and freezing are advisable. Experiments were devised or modified to test whether the locally-produced Polykan 57/500 high-density polyethylene containers were suitable for the storage of aqueous trace element samples which were to be collected in the Karroo Uranium Groundwater Hydrogeochemical Prospecting Project.

Some or all of the elements Li, Na, K, Rb, Cs, Mg, Ca, Sr, Cr, Mo, Mn, Fe, Co, Ni, Cu, Ag, Au, Zn, Pb and Tl are determined by Atomic Absorption Spectroscopy in soluble organic and total organic separates from thirty-six samples of South African carboniferous shales. The whole rock values for most of these elements in the samples are known and can be compared with the corresponding values of the organic fraction. A colloidal technique is developed to extract fairly pure kerogen from the shales. Rb, Cs, Ca, Cr, Co, Ni, Cu, Zn and Pb are concentrated in the organic fraction. The results for Rb, Cs and Ca are unexpected. The elements are apparently associated with a sub-fraction of the organic fraction. Several new organic geochemical parameters are developed to interpret the results. Interelement correlations in the various fractions of the shales, the relationship between metal content and organic content, the relationship between concentration of metals by organic matter and residence time, and the use of the metal content of the organic fraction as a paleosalinity test are discussed.

The reaction between ferrocytochrome c and hydrogen peroxide has been studied to determine possible reaction mechanisms. This was done by investigating the effect of various physical factors, such as hydrogen ion concentration, ionic strength and temperature, on the reaction and by studying the kinetics of the reaction. The study of pH and ionic strength showed that an ionization occurred at pH 7.8 which influenced the reactivity of the cytochrome c. The reaction was studied kinetically at pH 8.1 and pH 6.6. At pH 8.1 simple kinetics showed an uncomplicated reaction between ferrocytochrome c and hydrogen peroxide. The kinetic studies at pH 6.6 showed that ferrocytochrome c, hydrogen peroxide and ferricytochrome c (acting as a product catalyst) were involved in the reaction. The product catalysis complicated the kinetics and difficulty was experienced in fitting a suitable reaction mechanism. Copper ions have been found to catalyse reactions similar to that studied here. The effect of a copper histidine complex was therefore investigated on the reaction at pH 8.7. The copper complex was found to catalyse the oxidation of ferrocytochrome c by hydrogen peroxide and the kinetic studies of this oxidation showed that the reaction could be fitted to a simple mechanism which did not involve the formation of intermediate complexes. An unusual feature of the reaction was the ability of the cytochrome c, after complete oxidation, to undergo reduction, which is dependent on the presence of both hydrogen peroxide and copper ions.

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