A New Approach to Carbonate Alkalinity

Bogusław Pilarski, Anna M. Michałowska-Kaczmarczyk, Agustin G. Asuero, Agnieszka Dobkowska, Monika Lewandowska, Tadeusz Michałowski

CERKO Sp. z o.o. Sp. K., Gdynia, Poland.
Department of Analytical Chemistry, The University of Seville, Seville, Spain.
Department of Oncology, The University Hospital in Cracow, Cracow, Poland.
Faculty of Engineering and Chemical Technology, Cracow University of Technology, Cracow, Poland.

DOI: 10.4236/jasmi.2014.42009                

Abstract

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 (K_W) from a single pH titration curve. The parameters of the related functions are calculated according to the least squares method.

Keywords

Carbonate Alkalinity, pH Titration, Mathematical Modelling

Conflicts of Interest

The authors declare no conflicts of interest.

References

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