Continuous gradient method in flow microcalorimetry. Part II: Application to solution equilibria

A flow microcalorimeter operating in mixing mode generates a type of "continuous titrn." when one of the feeding pumps is connected to a continuous gradient generating device. The proper correction of the instrumental signal for the thermal lag of the calorimeter can be performed by chem. calibration, through an evaluation of the parameters of the Tian's equation, modified for the microcalorimeter. This equation relates the instrumental signal to the actual power developed by the reaction. The continuous exponential gradient method can be applied to the detn. of the enthalpy changes of metal-ligand-proton equil. reaction in soln. The enthalpies obtained for the protonation of D-cycloserine and for the formation of CuL and CuL2 complexes in the Cu(II)-Glycine system agree with published values. The computer programs, in BASIC language on an IBM-XT PC, used to process gradient data, are presented.