Polarographic determination of V(IV)/V(V) ratio in vanadate glasses

Polarographic reduction of vanadate and vanadyl ions in the presence of 0.4 mol l(-1) Na2SO4, 0.016 mol l(-1) H2SO4 and 8 x 10(-3) mol l(-1) ethylened iaminetetraacetic acid disodium salt (EDTA) has been investigated by direct current (DC) and direct current tast (DCT) polarographic techniques. Two w aves were obtained. The first wave corresponds to the reduction of V(V) to V(IV) and the second wave is due to the reduction of V(IV) to V(III). The c onstancy of I-d/C makes the microdetermination of both V(IV) and V(V) possi ble. The effects of different anions and cations on DC and DCT polarographi c waves were studied. A proposed procedure has been elaborated and applied successfully for the determination of V(IV)/V(V) ratio in vanadate glasses.