ANALYTICAL LIMITATIONS AND ERROR SOURCES IN COMPLEXATION STUDIES OF CU(II) WITH FULVIC-ACIDS BY POTENTIOMETRIC TITRATIONS

A potentiometric titration method has been used to obtain experimental data for acid-base and Cu complexation of soil fulvic acids. The unce rtainty associated to the data has been studied in order to prove a Ga ussian multiligand model, getting insight in the main sources of error . Based on this observations we concluded that it is difficult to eval uate the suitability of the model because the experimental values of c omplexed ligand obtained with sufficient certainty are a small percent age of the total complexation capacity of the ligand.