Synthesis, Formation Constants and Thermodynamic Functions for Some Bivalent Transition Metal Complexes with Di(3-cblorophenyl) Carbazone.

Abstract

Complex formation between transition metal ions viz., Cu(II), Ni(II), Zn(II), Cd(II), Co(II) and Mn(II) with di(3-chlorophenyl) carbazone (DMCIPC) has been investigated by potentiometric measurements of hydrogen ions liberated on complexation at 25, 35 and 45 ± 0.1 °C in 50% (v/v) aqueous-dioxane at an ionic strength of 0.1 M NaCIO₄. The method of Bjerrum and Calvin,  as modified by Irving and Rossotti. has been used to find out the values of n and pL. The stability constants have been calculated using a PC-XT computer by the weighted least squares method. The stability costants have also been calculated by Bjerrum half n method. The order of stability constants is found to be: Cu(II) > Ni(II) > Zn(II) > Cd(II) > Co(ll) > Mn(II). Thennodynamic functions,  ΔG,  ΔH and  ΔS have also been calculated.