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Updated: Jun 28, 2026
09:24
Application and Methodology of the Non-destructive 19F Time-domain NMR Technique to Measure the Content in Fluorine-containing Drug Products
Published on: August 22, 2017
Enthalpimetric determination of fluoride
1Department of Analytical Chemistry, Chemical Center, University of Lund, Lund, Sweden.
Talanta
|August 1, 1970
Summary
This study details a new injection calorimeter for precise sodium fluoride analysis and thermochemical measurements. It accurately quantifies fluoride and determines enthalpy changes in lead chloro-fluoride precipitation.
Area of Science:
- Analytical Chemistry
- Thermochemistry
- Physical Chemistry
Background:
- Accurate quantification of fluoride ions is crucial for various analytical and industrial applications.
- Thermochemical data, such as enthalpy changes, provide fundamental insights into chemical processes.
Purpose of the Study:
- To describe a novel injection calorimeter for analytical and thermochemical applications.
- To establish the accuracy and precision of the calorimeter for sodium fluoride determination.
- To measure the enthalpy of precipitation for lead chloro-fluoride.
Main Methods:
- Utilized an injection calorimeter for quantitative analysis of sodium fluoride.
- Employed flow microcalorimetry for trace fluoride analysis.
- Developed an ion-exchange system for fluoride separation from common anions.
Main Results:
- Determined sodium fluoride amounts between 6-8 mg with an error of +/-0.04 mg.
- Measured the enthalpy of precipitation (DeltaH) for lead chloro-fluoride as 36.6 +/- 0.3 kJ/mol in 1M ionic strength solutions.
- Achieved quantitative analysis of 40-400 µg sodium fluoride with +/-4 µg error using flow microcalorimetry.
Conclusions:
- The described injection calorimeter offers high precision for sodium fluoride quantification.
- The developed methods are suitable for both bulk and trace analysis of fluoride.
- The study provides valuable thermochemical data for lead chloro-fluoride precipitation.
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