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Updated: Aug 8, 2025
05:21
A Scalable Balz-Schiemann Reaction Protocol in a Continuous Flow Reactor
Published on: February 10, 2023
3.1K
Phase Transitions Equilibria of Five Dichlorinated Substituted Benzenes
Ana R R P Almeida1, Bruno D A Pinheiro1, Manuel J S Monte1
1Research Centre in Chemistry (CIQUP), Institute of Molecular Sciences (IMS), Department of Chemistry and Biochemistry (DQB), Faculty of Sciences, University of Porto (FCUP), Rua do Campo Alegre, 4169-007 Porto, Portugal.
Molecules (Basel, Switzerland)
|February 25, 2023
Summary
This study determined thermodynamic properties of five environmentally relevant chlorinated compounds. Key findings include sublimation and vaporization data, crucial for understanding their environmental behavior and chemical processes.
Area of Science:
- Physical Chemistry
- Environmental Chemistry
- Thermodynamics
Background:
- Chlorinated organic compounds can have significant environmental impacts.
- Understanding their thermodynamic properties is essential for predicting environmental fate and chemical behavior.
Purpose of the Study:
- To experimentally determine the thermodynamic properties of five chlorinated compounds.
- To investigate the contributions of substituents to sublimation thermodynamic properties.
Main Methods:
- Knudsen effusion technique for vapor pressure measurements of crystalline phases.
- Static method using capacitance diaphragm manometers for vapor pressure measurements.
- Differential scanning calorimetry (DSC) for fusion properties and heat capacities.
Main Results:
- Experimental vapor pressures were obtained for crystalline and liquid phases of dichlorobenzoic acid isomers and dichlorobenzonitriles.
- Standard molar enthalpies, entropies, and Gibbs energies of sublimation and vaporization were derived.
- Temperatures and enthalpies of fusion and isobaric heat capacities were determined using DSC.
Conclusions:
- The study provides crucial thermodynamic data for selected chlorinated compounds.
- This data aids in assessing their environmental impact and chemical reactivity.
- Substituent effects on sublimation properties were discussed, offering insights into molecular interactions.
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