Spectrophotometric study of Co(II), Ni(II), Cu(II), Zn(II), Pd(II) and Hg(II) complexes with isatin-β-thiosemicarbazone

Abstract

The composition and stability of the complexes of isatin-?-thiosemicarbazone with Co(II), Ni(II), Cu(II), Zn(II), Pd(II) and Hg(II) have been investigated using spectrophotometric method at 30?C and constant ionic strength of 0.1 mol dm-3 (KNO3) in 70 % ethanol. Experimental results indicate the formation of MeL and MeL2 complexes for Ni(II) and Co(II), and MeL for Cu(II), Zn(II), Pd(II) and Hg(II) complexes, whose stability constants, ?n, have been calculated using a computerized iterative method of successive approximation.