DIFFERENTIAL-PULSE POLAROGRAPHY (DPP) APPLIED FOR DETERMINING STABILITY-CONSTANTS OF CO(II), NI(II) AND ZN(II) COMPLEXES WITH ASCORBIC-ACID

Differential pulse polarography (DPP) was used to study: Me(n+)-H2AsC- NaClO4-H2O systems, where Me(n+) = Ni2+, Co2+ or Zn2+. The polarograms obtained show that the following complexes are formed in the investig ated systems: [Me(HAsc)]+; [Me(HASC)2]0, [Me(HAsc)3]-, [Me(Asc)r and [ Me(Asc)2]2-. The values of stability constants beta(n) for the identif ied complexes, calculated from the experimental data obtained by DPP a re in agreement with the beta(n) values determined by other methods.