Determination of overall stability constants of uranyl acetate complexes by ph measurements

The complexation study provides stability constant data of metal complexes. The knowledge of stability constants of metal complexes is important in view of finding the best complexing agent for extraction and separation of metal ions. In the present study, the data of hydrogen ions activity obtained from ph analysis was utilized in finding overall stability constants of uranyl acetate complexes on the basis of plot of function 'F' vs. the equilibrium concentration of acetate ions '[A]'. The magnitude of function 'F' was evaluated, where 'n' is the number of moles of ligand complexed per mole of uranyl ions and [A] is the equilibrium concentration of acetate ions. The overall stability constants were calculated. The values of log beta/sub 1/, log beta/sub 2/ and log beta/sub 3/ were found to be 2.75, 4.75 and 6.81 respectively which are close to the reported data in literature. It was concluded that ph meter may be satisfactorily utilized in the evaluation of overall stability constants of metal complexes with anions of weak acids. (Orig./A.B.)