Complexometric determination of palladium(II) using thioacetamide as a selective masking agent
P Parameshwara1, J Karthikeyan, A Nityananda Shetty
1Department of Chemistry, National Institute of Technology Karnataka, Surathkal, Srinivasnagar 575 025, Karnataka, India.
Annali Di Chimica
|June 1, 2006
Summary
A new complexometric method accurately determines palladium(II) using thioacetamide as a masking agent. This rapid technique is effective even with interfering metal ions present.
Area of Science:
- Analytical Chemistry
- Inorganic Chemistry
Background:
- Accurate determination of palladium(II) is crucial for various applications.
- Existing complexometric methods may face interference from diverse metal ions.
Purpose of the Study:
- To develop a simple, rapid, and accurate complexometric method for palladium(II) determination.
- To utilize the selective masking property of thioacetamide for enhanced accuracy.
Main Methods:
- Complexometric titration involving ethylenediaminetetraacetic acid (EDTA) and palladium(II).
- Selective masking of palladium(II) using thioacetamide.
- Back titration of released EDTA with a standard lead nitrate solution.
- Use of xylenol orange as an indicator at pH 5-5.5.
Main Results:
- The method provides reproducible and accurate results for palladium(II) concentrations ranging from 0.5 mg to 17.80 mg.
- Achieved a low relative error of +/- 0.16% and a coefficient of variation not exceeding 0.26%.
- Demonstrated effectiveness in the presence of diverse metal ions.
Conclusions:
- The proposed complexometric method is highly accurate and reliable for palladium(II) determination.
- Thioacetamide effectively masks palladium(II), enabling precise analysis.
- The method is applicable to real-world samples, including palladium complexes, catalysts, and synthetic alloys.
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