DEVELOPMENT AND UNCERTAINTY ASSESSMENT OF SECONDARY METHOD FOR pH MEASUREMENT IN PHYSICOCHEMICAL MEASUREMENTS

Authors

• Sarvar Rakhmatullaev, Tashkent State Technical University. Address: 2 Universitet st., 100095, Tashkent, Uzbekistan. E-mail: sarvar.raxmatullayev90@gmail.сom (orсid.org/ 0000-0001-7901-6600);Follow
• Dostonbek Xujakulov, Uzbek National Institute of Metrology. Address: 333 B Farobiy st., 100174, Tashkent, Uzbekistan;
• Mohinur Nigmatova, Uzbek National Institute of Metrology. Address: 333 B Farobiy st., 100174, Tashkent, Uzbekistan. E-mail: mohinurnigmatova05@gmail.сom.

Abstract

In physicochemical measurements across various industries, laboratory analyses commonly require the determination of pH as an indicator of hydrogen ion activity in aqueous solutions. Ensuring the accuracy and reliability of these measurements, obtaining precise readings from pH measuring instruments, and maintaining overall measurement quality represent critical challenges in guaranteeing the safety of both products and processes. This requires constant monitoring, accuracy assessment, calibration, metrological verification, and control of measuring instruments. In this case, it should be carried out not with solutions prepared in any laboratory, but with certified reference materials (СRM) with appropriate regulatory framework, ensuring metrological observation.

This article presents the requirements for the preparation of secondary pH standard samples (buffer solutions) to ensure the metrological traceability of pH measurements. The research encompasses the preparation and characterization of secondary standard solutions, the design and operational requirements of the measuring apparatus, analysis of the experimental results obtained during the course of the research, and the evaluation of measurement uncertainty with consideration of contributing influencing factors.

First Page

47

Last Page

53

References

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Recommended Citation

Rakhmatullaev, Sarvar; Xujakulov, Dostonbek; and Nigmatova, Mohinur (2026) "DEVELOPMENT AND UNCERTAINTY ASSESSMENT OF SECONDARY METHOD FOR pH MEASUREMENT IN PHYSICOCHEMICAL MEASUREMENTS," Chemical Technology, Control and Management: Vol. 2026: Iss. 4, Article 6.
DOI: https://doi.org/10.59048/2181-1105.1753