Reducible and Irreducible Components of the pH Value in Dilute Aqueous Solutions of Sodium Chloride


  • L.A. Bulavin Taras Shevchenko National University of Kyiv, Faculty of Physics
  • N.P. Malomuzh Odessa I.I. Mechnikov National University
  • O.V. Khorolskyi Poltava V.G. Korolenko National Pedagogical University



aqueous solution, sodium chloride, pH, reducible component, irreducible component


Main attention is paid to the definition of the reducible and irreducible components of pH in aqueous salt solutions and to the determination of their temperature and concentration dependences. It is shown that the temperature dependence of the reducible pH component in dilute aqueous solutions of sodium chloride has a linear character and differs from that in pure water only by the value of its slope, which increases, as the salt concentration grows. At the same time, the temperature dependence of the irreducible pH component is non-monotonic and has a minimum at the temperature that is optimal for the human and mammalian life activities (36.6 C). The existence of a characteristic salt concentration dividing the family of the temperature dependences of pH into two subfamilies with different behaviors of their temperature dependences has been established.


D.U. Silverthorn. Human Physiology: An Integrated Approach (Pearson, 2018) [ISBN: 978-0134605197].

J.E. Hall, M.E. Hall. Guyton and Hall Textbook of Medical Physiology (Elsevier, 2020) [ISBN: 978-0323597128].

L.A. Bulavin, N.P. Malomuzh, O.V. Khorolskyi. Temperature and concentration dependences of pH in aqueous NaCl solutions with dissolved atmospheric CO2. Ukr. J. Phys. 67, 833 (2022).

O.D. Stoliaryk, O.V. Khorolskyi. Influence of atmospheric carbon dioxide on the acid-base balance in aqueous sodium chloride solutions. Ukr. J. Phys. 67, 515 (2022).

R.G. Bates. Determination of pH: Theory and Practice (John Wiley and Sons, 1964) [ISBN: 9780471056461].

R.P. Buck, S. Rondinini, A.K. Covington, F.G.K. Baucke, C.M.A. Brett, M.F. Camoes, M.J.T. Milton, T. Mussini, R. Naumann, K.W. Pratt, P. Spitzer, G.S. Wilson. Measurement of pH. Definition, standards, and procedures (IUPAC Recommendations 2002). Pure Appl. Chem. 74, 2169 (2002).

I. Leito, L. Strauss, E. Koort, V. Pihl. Estimation of uncertainty in routine pH measurement. Accred. Qual. Assur. 7, 242 (2002).

G. Meinrath, P. Spitzer. Uncertainties in determination of pH. Microchim. Acta 135, 155 (2000).

R. Kadis, I. Leito. Evaluation of the residual liquid junction potential contribution to the uncertainty in pH measurement: A case study on low ionic strength natural waters. Analyt. Chim. Acta 664, 129 (2010).

V. Souza, A. Pires Ordine, I.C.S. Fraga, M.A. Getrouw, P.P. Borges, J.C. Damasceno, P.R.G. Couto. Effect of NaCl and HCl concentrations on primary pH measurement for the certification of standard materials. Braz. Arch. Biol. Technol. 49 (Special), 79 (2006).

T.S. Light, S.L. Licht. Conductivity and resistivity of water from the melting to critical point. Anal. Chem. 59, 2327 (1987).

M. Yizhak. Ions in Water and Biophysical Implications (Springer, 2012) [ISBN: 978-94-007-4646-6].

V. Makhlaichuk, N.P. Malomuzh. Peculiarities of structure in aqueous electrolyte solutions and specificity of hydration effects. J. Mol. Liq. 349, 118088 (2021).

A.A. Guslisty, N.P. Malomuzh, A.I. Fisenko. Optimal temperature for human life activity. Ukr. J. Phys. 63, 809 (2018).

A.I. Fisenko, N.P. Malomuzh. Role of the H-bond network in the creation of life-giving properties of water. Chem. Phys. 345, 164 (2008).

A.I. Fisenko, N.P. Malomuzh. To what extent is water responsible for the maintenance of the life for warm-blooded organisms? Int. J. Mol. Sci. 10, 2383 (2009).

L.A. Bulavin, A.I. Fisenko, N.P. Malomuzh. What water properties are responsible for the physiological temperature interval limits of warm-blooded organisms? arXiv 1307.7295 (2013).

L.A. Bulavin, V.Y. Gotsulskyi, N.P. Malomuzh, A.I. Fisenko. Crucial role of water in the formation of basic properties of living matter. Ukr. J. Phys. 65, 794 (2020).

L.A. Bulavin, N.P. Malomuzh. Upper temperature limit for the existence of the alive matter. J. Mol. Liq. 124, 136 (2006).

V. Bardik, A.I. Fisenko, S. Magaz'u, N.P. Malomuzh. The crucial role of water in the formation of the physiological temperature range for warm-blooded organisms. J. Mol. Liq. 306, 112818 (2020).

L. Melnikov'a, V.I. Petrenko, M.V. Avdeev, V.M. Garamus, L. Alm'asy, O.I. Ivankov, L.A. Bulavin, Z. Mitr'oov'a, P. Kopˇcansk'y. Effect of iron oxide loading on magnetoferritin structure in solution as revealed by SAXS and SANS. Colloids and Surfaces B: Biointerfaces 123, 82 (2014).

O.A. Kyzyma, T.D. Kyrey, M.V. Avdeev, M.V. Korobov, L.A. Bulavin, V.L. Aksenov. Non-reversible solvatochromism in N-methyl-2-pyrrolidone/toluene mixed solutions of fullerene C60. Chem. Phys. Lett. 556, 178 (2013).

V.I. Petrenko, M.V. Avdeev, L. Alm'asy, L.A. Bulavin, V.L. Aksenov, L. Rosta, V.M. Garamus. Interaction of mono-carboxylic acids in benzene studied by small-angle neutron scattering. Colloid. Surface. A 337, 91 (2009).

A. Borowik, Y. Prylutskyy, L. Kawelski, O. Kyzyma, L. Bulavin, O. Ivankov, V. Cherepanov, D. Wyrzykowski, R. Ka'zmierkiewicz, G. Golu'nski, A. Woziwodzka, M. Evstigneev, U. Ritter, J. Piosik. Does C60 fullerene act as a transporter of small aromatic molecules? Colloid. Surface. B 164, 134 (2018).

O.V. Khorolskyi, Y.D. Moskalenko. Calculation of the macromolecular size of bovine serum albumin from the viscosity of its aqueous solutions. Ukr. J. Phys. 65, 41 (2020).



How to Cite

Bulavin, L., Malomuzh, N., & Khorolskyi, O. (2023). Reducible and Irreducible Components of the pH Value in Dilute Aqueous Solutions of Sodium Chloride. Ukrainian Journal of Physics, 68(3), 177.



Physics of liquids and liquid systems, biophysics and medical physics

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