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Updated: Jan 2, 2026
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Near-Infrared Temperature Measurement Technique for Water Surrounding an Induction-heated Small Magnetic Sphere
Published on: April 30, 2018
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Near Infrared Spectrophotometric Method for the Determination of Hydration Numbers
Summary
This study introduces a novel method using water's 980 mμ absorption band to determine hydration numbers. The technique measures "free" water concentration changes upon electrolyte addition, yielding accurate results comparable to existing methods.
Area of Science:
- Analytical Chemistry
- Physical Chemistry
- Spectroscopy
Background:
- Determining ion hydration numbers is crucial in understanding electrolyte solutions.
- Traditional methods for hydration number determination can be complex and time-consuming.
Purpose of the Study:
- To develop a new, accurate spectroscopic method for determining hydration numbers.
- To apply this method to electrolyte solutions and validate its effectiveness.
Main Methods:
- Utilizing the 980 mμ absorption band of water.
- Measuring the decrease in "free" water concentration via absorbance changes.
- Employing electrolyte addition (chromic chloride, nitrate salts) in water-methanol solutions.
Main Results:
- Quantified the decrease in "free" water concentration.
- Extrapolated data to determine hydration numbers in pure water.
- Obtained results consistent with established hydration number determination methods.
Conclusions:
- The 980 mμ absorption band provides a reliable basis for a new hydration number determination technique.
- This spectroscopic method offers an accurate alternative for studying electrolyte hydration.
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