0000000000637171
AUTHOR
G. Ramis
A program for the simultaneous potentiometric determination of protonation constants and electrode calibration parameters
A program for the potentiometric determination of the protonation constants of mononuclear polyprotic substances is described. A maximum of twelve parameters can be determined simultaneously, including up to six protonation constants, four electrode calibration parameters, the protolysis constant of the solvent and the titrant concentration. Optimization is carried out by using the non-simplified Newton-Raphson method, which is potentiated by the Marquardt algorithm and a distance speeding-up coefficient. A direct search method is also used to improve the initial set of values. Variances are calculated very accurately, since the real Hessian function is used. Statistical weights and ionic s…
A comparative study of the application of the method of least-squares in the potentiometric determination of protonation constants.
Methods of simple and multiple linear regression applied to the potentiometric determination of protonation constants of diprotic and triprotic acids are studied critically. The best way of fitting the data, according to the order of magnitude of the constants, is established. The conclusions are checked by calculating the protonation constants of succinic and citric acids.