Influence of Atmospheric Carbon Dioxide on the Acid-Base Balance in Aqueous Sodium Chloride Solutions


  • O.D. Stoliaryk Odessa I.I. Mechnikov National University
  • O.V. Khorolskyi Poltava V.G. Korolenko National Pedagogical University



aqueous solution, sodium chloride, acid-base balance, carbon dioxide, relaxation time


The influence of atmospheric carbon dioxide (CO2) on the acid-base balance (pH) in dilute aqueous solutions of sodium chloride (NaCl) at the concentrations corresponding to 540, 675, 900, and 1620 water molecules per sodium or chlorine ion has been studied in a temperature interval of 294–323 K. The pH relaxation time in aqueous NaCl solutions with dissolved atmospheric CO2 and the corresponding temperature and salt-concentration dependences are calculated. The similarity of the temperature behavior of the pH relaxation times in NaCl solutions with various salt concentrations is demonstrated. To clarify the nature and features of this phenomenon, the corresponding Debye radii are calculated, and it is shown that the electrostatic interaction does not play a decisive role in the examined solutions, thus not affecting appreciably the molecular processes. An attempt is made to construct a rigorous theoretical substantiation of the mechanisms driving the establishment of the pH equilibrium in pure water and in water contacting with atmospheric CO2. The calculation results obtained using the derived formula correlate well with experimental results. Atmospheric CO2 is proved to have a significant effect on the change of pH in water and aqueous NaCl solutions.


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How to Cite

Stoliaryk, O., & Khorolskyi, O. (2022). Influence of Atmospheric Carbon Dioxide on the Acid-Base Balance in Aqueous Sodium Chloride Solutions. Ukrainian Journal of Physics, 67(7), 515.



Physics of liquids and liquid systems, biophysics and medical physics