The thermodynamic characteristics of formation of cobalt(II) ion complexes with D,L-threonine in aqueous solution

The heat effects of interaction of cobalt(II) ions with D,L-threonine in aqueous solution and the corresponding heats of dilution were determined by direct calorimetry at 288.15, 298.15, and 308.15 K and ionic strength values of 0.25, 0.50, and 0.75 (against the background of potassium nitrate). The standard heat effects of formation of CoThr⁺, CoThr₂, and CoThr ₃ ^? complexes were determined by extrapolation to zero ionic strength according to the equation with one individual parameter. The standard enthalpies of formation of complex particles in the hypothetical nondissociated state in aqueous solution were calculated.