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Published on: February 7, 2017
2-methoxyethanol as a solvent for conductometric acid-base titrations.
1Department of Chemistry, Hope College, Holland, Michigan 49423, U.S.A.
Talanta
|September 1, 1975
Summary
Conductometric titrations using 1,3-diphenylguanidine (DPG) in 2-methoxyethanol showed accurate results for most organic acids. However, difunctional acids yielded less defined titration curves, indicating their behavior as weak electrolytes.
Area of Science:
- Analytical Chemistry
- Organic Chemistry
Background:
- Non-aqueous titrations are crucial for analyzing organic acids.
- 2-methoxyethanol is a suitable solvent for conductometric studies.
- 1,3-diphenylguanidine (DPG) is an effective base for titrating weak acids.
Purpose of the Study:
- To evaluate the effectiveness of conductometric titrations for various organic acids in 2-methoxyethanol.
- To determine the behavior of different organic acids as electrolytes in this solvent.
- To compare results with titrations in other non-aqueous media.
Main Methods:
- Conductometric titrations were performed on a series of organic acids.
- 1,3-diphenylguanidine (DPG) was used as the titrant.
- Electrolyte conductance was measured as a function of concentration.
Main Results:
- Excellent recoveries were achieved for benzoic, p-chlorobenzoic, picric acids, phenylphenol, and barbital.
- Good results were obtained for dicarboxylic acids like phthalic and adipic acid.
- Titration curves for salicylic and p-hydroxybenzoic acids were not clearly defined.
- Organic acids studied were confirmed as weak electrolytes in 2-methoxyethanol.
Conclusions:
- Conductometric titration with DPG in 2-methoxyethanol is effective for many organic acids.
- Difunctional acids present challenges due to less defined titration curves.
- The study confirms the weak electrolyte nature of these substances in the chosen solvent.
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