Determining the identification of parameters for the mathematical model of electrical conductivity in conductometric models

Authors

DOI:

https://doi.org/10.15587/1729-4061.2026.352348

Keywords:

conductometry, Fisher matrix, parameter non-identification, weak electrolytes, association constant, electrical conductivity

Abstract

Using an aqueous solution of acetic acid an example, this study has investigated a mathematical model of the electrical conductivity of weak electrolyte dilute solutions.

To resolve the issue of identification and reliability in determining the parameters for the mathematical model of the electrical conductivity of dilute solutions of weak electrolytes, the determinant of the Fisher information matrix was calculated.

The issues related to determining the association constants and the limiting molar electrical conductivity of weak electrolytes under different conditions of experimental experiments were identified and explained.

This paper reports results of mathematical processing of conductometric data for aqueous solutions of acetic acid.

It was established that for weak, associated electrolytes, when determining the association constants and the limiting molar coefficients, it is necessary to take into account the existence of a correlation between them.

It is proven that at large values of the association constant (5.58 * 104 mol/L) the determinant of the Fisher information matrix is close to zero and there is a structural non-identification of parameters for the mathematical model of electrical conductivity of dilute solutions of weak electrolytes.

It is shown that the results of mathematical processing of conductometric data for aqueous solutions of acetic acid indicate the presence of structural non-identification. This is confirmed by the values of the determinant of the Fisher information matrix, which is equal to 5.5 * 10-8, and the normalized index of 0.988.

Analysis of the shape of the surface of the objective functions of the studied mathematical models and the form of the average error ellipse reveals the existence of a canyon with an almost flat bottom, which complicates the interpretation and reliability of parameters for the mathematical model of electrical conductivity.

The results confirm the possibility of structural non-identification of parameters for the mathematical model of the electrical conductivity of dilute solutions of weak electrolytes

Author Biographies

Vitaliy Chumak, State University «Kyiv Aviation Institute»

Doctor of Chemical Sciences, Professor

Department of Ecology, Chemistry and Chemical Technology

Mariia Maksymiuk, State University «Kyiv Aviation Institute»

PhD, Associate Professor

Department of Ecology, Chemistry and Chemical Technology

Andrii Kоpаnytsia, State University «Kyiv Aviation Institute»

PhD Student

Department of Ecology, Chemistry and Chemical Technology

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Determining the identification of parameters for the mathematical model of electrical conductivity in conductometric models

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Published

2026-02-26

How to Cite

Chumak, V., Maksymiuk, M., & Kоpаnytsia A. (2026). Determining the identification of parameters for the mathematical model of electrical conductivity in conductometric models. Eastern-European Journal of Enterprise Technologies, 1(6 (139), 16–24. https://doi.org/10.15587/1729-4061.2026.352348

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Technology organic and inorganic substances