EFFECT OF THE NICKEL(II) TRISDIPYRIDIL COMPLEXES ON THE REDUCTION KINETICS OF THE LEAD(II) DIPYROPHOSPHATE COMPLEXES AT THE MERCURY-ELECTRODE

The influence exerted by 2,2'-dipyridil molecules and the trisdipyridi l complexes of nickel(II) adsorbed at mercury on the electroreduction rate of dipyrophosphate complexes of lead(II) at the dropping and stat ionary mercury electrodes is studied in solutions with different conce ntrations of 2,2'-dipyridil and complexes of nickel(II), sodium pyroph osphate, and sodium nitrate (pH similar to 8). The electroreduction ra te of the Pb(P2O7)(2)(6-) complexes is found to change slightly upon a dsorption of 2,2'-dipyridil molecules and decrease dramatically upon a dsorption of the Ni(dipy)(3)(2+) complexes and their associates with a nions of the supporting electrolyte. Adsorption of the trisdipyridil c omplexes of nickel(II) at the negatively charged surface of the mercur y electrode is shown to be described by the Frumkin adsorption isother m with positive values of the attraction constant.