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N-substituted phenothiazines as redox indicators in bromatometry
1Department of Post-graduate Studies and Research in Chemistry, University of Mysore, Manasa Gangotri, Mysore, India.
Talanta
|March 1, 1979
Summary
Phenothiazine derivatives like diethazine hydrochloride serve as sharp indicators in bromate titrations for estimating quinol and metol. This study details a simple, accurate method using these compounds for quantitative analysis.
Area of Science:
- Analytical Chemistry
- Organic Chemistry
Background:
- Phenothiazine derivatives are widely used in pharmaceuticals.
- Titration methods require precise indicators for accurate results.
Purpose of the Study:
- To evaluate phenothiazine derivatives as indicators in bromate titrations.
- To develop a simple and accurate method for estimating quinol and metol.
Main Methods:
- Studied six phenothiazine derivatives: diethazine hydrochloride, butaperazine dimaleate, trifluoperazine hydrochloride, promethazine hydrochloride, prochlorperazine maleate, and chlorpromazine hydrochloride.
- Utilized bromate titration for the quantitative analysis of quinol, metol, and ascorbic acid.
- Determined the formal potentials of the studied indicators.
Main Results:
- All six studied phenothiazine derivatives exhibited sharp, reversible color changes at the equivalence point.
- The formal potentials of these indicators were successfully determined.
- A straightforward and accurate method for the estimation of quinol and metol was established.
Conclusions:
- Phenothiazine derivatives are effective indicators for bromate titrations.
- The developed method offers a simple and accurate approach for quantifying quinol and metol.
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