Advertisement

Uncertainty Evaluation of pH Measured Using Potentiometric Method

  • Józef Wiora
Part of the Advances in Intelligent Systems and Computing book series (AISC, volume 323)

Abstract

Determination of pH using a typical glass electrode requires prior calibration in order to determine the electrode parameters. Knowledge about uncertainties of the parameters is insufficient to calculate the uncertainty of measured pH because of existing correlation. In the paper, an example illustrating the problem is presented. Two ways of proper uncertainty assessment are suggested: (1) analytical with removing the correlated variables and (2) numerical using Monte Carlo simulations. The second one seems to be much less time-consuming and allows easier investigations of the uncertainty properties.

Keywords

pH Uncertainty propagation Monte Carlo method 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Sheppard, N.F.J., Guiseppi-Elie, A.: 71. pH Measurement. Electrical Engineering Handbook Series. In: The Measurement, Instrumentation, and Sensors: Handbook. Springer (1999)Google Scholar
  2. 2.
    Morf, W.E.: The Principles of Ion-Selective Electrodes and of Membrane Transport. Akadémiai Kiadó, Budapest (1981)Google Scholar
  3. 3.
    Cammann, K.: Working with ion-selective electrodes: chemical laboratory practice. Springer (1979)Google Scholar
  4. 4.
    Spitzer, P., Fisicaro, P., Meinrath, G., Stoica, D.: pH buffer assessment and Pitzer’s equations. Accreditation and Quality Assurance 16, 191–198 (2011)CrossRefGoogle Scholar
  5. 5.
    Camões, M.F.: The quality of pH measurements 100 years after its definition. Accreditation and Quality Assurance 14, 521–523 (2009)CrossRefGoogle Scholar
  6. 6.
    Midgley, D., Torrance, K.: Potentiometric Water Analysis, 2nd edn. John Wiley & Sons, Inc., Chichester (1991)Google Scholar
  7. 7.
    Bakker, E., Bühlmann, P., Pretsch, E.: The phase-boundary potential model. Talanta 62, 843–860 (2004)CrossRefGoogle Scholar
  8. 8.
    IUPAC: Potentiometric selectivity coefficients of ion-selective electrodes. part I. inorganic cations (technical report). Pure Appl. Chem. 72(10), 1851–2082 (2000)Google Scholar
  9. 9.
    Kozyra, A., Wiora, J., Wiora, A.: Calibration of potentiometric sensor arrays with a reduced number of standards. Talanta 98, 28–33 (2012)CrossRefGoogle Scholar
  10. 10.
    Sokalski, T., Lewenstam, A.: Application of Nernst-Planck and Poisson equations for interpretation of liquid-junction and membrane potentials in real-time and space domains. Electrochem. Commun. 3, 107–112 (2001)CrossRefGoogle Scholar
  11. 11.
    Wiora, J., Wiora, A.: A system allowing for the automatic determination of the characteristic shapes of ion-selective electrodes. In: Pisarkiewicz, T. (ed.) Optoelectronic and Electronic Sensors VI, Zakopane, October. Proceedings of SPIE, vol. 6348 (October 2006)Google Scholar
  12. 12.
    Wiora, J.: About the uncertainty of concentration standards applied in the calibration of potentiometric ion-selective electrodes. Measurement Automation and Monitoring 54(5), 318–321 (2008) (in Polish)Google Scholar
  13. 13.
    JCGM: Evaluation of measurement data – Guide to the expression of uncertainty in measurement (2008)Google Scholar
  14. 14.
    JCGM: Evaluation of measurement data – Supplement 1 to the “Guide to the expression of uncertainty in measurement” – Propagation of distributions using a Monte Carlo method (2008)Google Scholar

Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Institute of Automatic ControlSilesian University of TechnologyGliwicePoland

Personalised recommendations