Measurement Uncertainty Calculations for pH Value Obtained by an Ion-Selective Electrode

Abstract

An assessment of measurement uncertainty is a task, which has to be the final step of every chemical assay. Apart from a commonly applied typical assessment method, Monte Carlo (MC) simulations may be used. The simulations are frequently performed by a computer program, which has to be written, and therefore some programming skills are required. It is also possible to use a commonly known spreadsheet and perform such simulations without writing any code. Commercial programs dedicated for the purpose are also available. In order to show the advantages and disadvantages of the ways of uncertainty evaluation, i.e., the typical method, the MC method implemented in a program and in a spreadsheet, and commercial programs, a case of pH measurement after two-point calibration is considered in this article. The ways differ in the required mathematical transformations, degrees of software usage, the time spent for the uncertainty calculations, and cost of software. Since analysts may have different mathematical and coding skills and practice, it is impossible to point out the best way of uncertainty assessment—all of them are just as good and give comparable assessments.

Current Limitations for Predicting Liquid Dispersion in Continuous Flow Bubble Columns Using CFD

“…The temporal evolution of the CFD and experiment tracer responses was compared (Figure 4), corresponding to the centerline (r = 0 m) of the column at two different axial positions (z = 1.05 and 1.84 m). Although no single uncertainty estimate can be attributed to a pH measurement procedure, it has been shown that the pH measurement uncertainty for commercial glass electrodes is less than 0.05 pH units [34]. All data in Figure 4 were normalized using the highest measurement within a set for ease of comparison.…”

Implementasi Green Economy pada Sistem Instalasi Pengolahan Air Limbah Tahu dan Sensor Terintegrasi di Kediri

“…Pada pH meter, bahasa pemrograman pada Arduino IDE yang menjadi template standar perlu dilakukan perombakan dikarenakan adanya selisih nilai dengan pH meter digital portable. Sehingga, tim PKM melakukan perombakan program fungsi pembacaan pH dengan mengikuti persamaan berikut dengan buffer pH 4,01 dan 6,89 sebagai acuan standar voltase kalibrasi (EpH4 dan EpH7) (Wiora & Wiora, 2018),…”

Ion sensing pencil: Draw your own sensor

“…We have also developed an MS Excel sheet for calculations of unknown concentration and its associated standard deviation according to protocols suggested by Wiora and Wiora. 34 This offered simplicity and automatization of data processing thus further contributing to the notion of suitability of the use of ISPs by non-trained personnel. Figure 5 illustrates the use of digital multimeter as a readout device used to determine salt content in bottled drinking water and instant soup obtained from a local shop.…”