Conductometric and Spectrophotometric Studies of the Thermodynamics Complexation of Cu2+, Hg2+, Ni2+, Zn2+, Cd2+ and Co2+ Ions with (E)-(Pyridine -2-Ylmethylidene)({2-(E)-(Pyridine-2- Ylmethylidene)Amino]ethyl} Ligands in Acetonitrile Solution and Comparison of Their Behaviors

Abstract

<span style="font-family: Times New Roman;">A new pyridine derivative ligand, (E)-(Pyridine-2-ylmethylidene)({2-(E)-(Pyridine-2-ylmethylidene)amino]ethyl}has been synthesized and k_f value of its complexes with Cu²⁺, Ni²⁺, Cd²⁺, Zn²⁺, Hg²⁺ and Co²⁺has been determined by spectrophotometric and conductometric methods in acetonitrile at various temperatures. The formation constants (K_ß= K₁ × K₂) of the 1:1 and 1:2 (metal ion to ligand) complexes were calculated by computer fitting of the absorbance-mole ratio data, and molar conductance-mole ratio data at different temperatures, and found that complexes to vary in acetonitrile solvent in the order of Cu²⁺ >Hg²⁺>Zn²⁺>Co²⁺> Cd²⁺> Ni²⁺>Ag⁺. The enthalpy and entropy changes of the complexation reaction were evaluated from the temperature dependence of formation constants.</span>