The article provides experimental data applied to the determination of
carbonate alkalinity (CAM) according to modified Gran II functions. CAM is
related to the mixtures NaHCO3 + Na2CO3 and Na2CO3 + NaOH. In addition to the determination of equivalence volumes, one of the
main novelties of the proposed method is the possibility of determining the
activity coefficient of hydrogen ions (γ).
Moreover, CAM can be used to calculate the dissociation constants (K1,
K2) for carbonic acid and the ionic product of water (KW)
from a single pH titration curve. The parameters of the related functions are
calculated according to the least squares method.
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