The thermodynamic characteristics of complex formation between Ni2+ ions and D,L-threonine in aqueous solution

摘要

The heat effects of interaction between solutions of D,L-threonine and Ni(NO3)(2) were measured by direct calorimetry at 298.15 K and ionic strength values of from 0.5 to 1.5 (KNO3). The heat effects of formation of the NiL+, NiL2, and NiL3- complexes were calculated. The influence of background electrolyte concentration on the heats of complex formation in the Ni2+-D,L-threonine system was studied. The standard heat effects of formation of Ni2+ stop complexes with D,L-threonine were obtained by extrapolation to zero ionic strength. The standard enthalpies of formation of NiL+, NiL2, and NiL3- in aqueous solution were calculated.