Collect. Czech. Chem. Commun. 1982, 47, 3243-3251

Polarographic electrode process of antimony(III) complexes with complexones

Wang Er-kang

Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130 021 China


Antimonous ions yield in a solution of 4M sodium chloride a well-defined reduction wave. With increasing concentration of EDTA or CDTA a new cathodic wave appears at more negative potentials. The first (more positive) wave is kinetically controlled. We calculate the stability constant and the thermodynamic functions of antimony(III) complexone complexes from the shift of half-wave of the kinetic wave and their dissociation constant from the kinetic current under given conditions, β = 3 . 1019, kd = 2.8 . 1013 s-1 for SbY, β = 6 . 1024, kd = 8.8 . 1018 s-1 for SbZ. The rate constant of electrode reaction proper of the antimony(III) complexes with complexone is also calculated and the mechanism of the whole process is discussed.