Solvent effects on protonation, chellation and stability constants of Pd(II)- 4-2-(pyridyl azo)-resorcinol in aqueous, mixed organic solvents and non-ionic micellar media

This paper is a descriptive report focusing on the trends of complex formation of palladium(II) and 4-2-(pyridyl azo)-resorcinol in different media under optimized conditions by using Uv/vis. spectrophotometric technique. All the affecting chemical variables have been investigated. At first, by application of job and mole ratio methods the stoichiometric M:L ratio was confirmed to be 1:1. By calculation the mean molar absorptivity coefficient and equilibrium concentration of complex, its stability constants were determined over a wide range of ionic strengths in presence of KCl as the background salt. The results showed the thermodynamically endurance of the complex and applicability of utilization of organic solvents. Satisfactory agreement between experimental and theoretical formation constants verifies the accuracy of the proposed method.