Thermodynamic characteristics of complexation between Ho3+ and ethylenediamine-N,N'-disuccinic acid in aqueous solutions at 298.15 K

The thermodynamic characteristics of complexation between ethylenediamine- N , N '-disuccinic acid (H 4 Y; EDDA) and Ho 3+ ion were determined calorimetrically and potentiometrically at 298.15 K and ionic strengths of 0.1, 0.5, 1.0, and 1.5 (KNO 3 ). The log K , Δ r G , Δ r H , and Δ r S values for the formation of HoY – and HOHY complexes were calculated at the studied and zero ionic strength values. The changes in thermodynamic parameters of the reactions are discussed.