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Updated: Jun 28, 2026
07:32
Dynamic Electrochemical Measurement of Chloride Ions
Published on: February 5, 2016
Chromazurol S ion-selective electrode for chelatometric titration
1Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Japan.
Talanta
|April 1, 1977
Summary
A novel Chromazurol S ion-selective electrode was developed for chelatometric titrations. This electrode enables accurate determination of metal ions like copper and nickel using EDTA.
Area of Science:
- Analytical Chemistry
- Electrochemistry
- Chemical Sensors
Background:
- Ion-selective electrodes (ISEs) are crucial for chemical analysis.
- Chromazurol S is a useful indicator dye for metal ion complexation.
- Developing new ISEs enhances analytical capabilities.
Purpose of the Study:
- To construct and evaluate a liquid membrane Chromazurol S ion-selective electrode.
- To apply this electrode in chelatometric titrations.
- To determine the electrode's performance characteristics.
Main Methods:
- Construction of a liquid membrane electrode using a Chromazurol S-zephiramine ion-pair in nitrobenzene.
- Testing the electrode's Nernstian response range and linearity.
- Application in the chelatometric titration of Cu(II), Ni(II), Fe(III), and Pb(II) with EDTA.
Main Results:
- A linear Nernstian response for the Chromazurol S anion was observed in the range of 10(-2)-10(-6)M.
- The optimal ion-pair concentration in the membrane was found to be 10(-4)M.
- The electrode demonstrated successful application in titrating Cu(II), Ni(II), Fe(III), and Pb(II) with EDTA.
Conclusions:
- The developed Chromazurol S liquid membrane electrode is effective for chelatometric titrations.
- This ISE offers a reliable method for quantifying specific metal ions.
- The electrode shows potential for routine analytical applications in chemistry.
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