Standard Methods: 4500-SO42- C: Sulfate by Gravimetric Analysis with Ignition of Residue
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Official Method Name
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Gravimetric Analysis with Ignition of Residue |
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Current Revision
| Standard Methods Online |
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Media
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WATER |
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Instrumentation
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Gravimetry |
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Method Subcategory
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Inorganic |
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Method Source
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Citation
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Brief Method Summary
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Sulfate is precipitated in an HCl solution as barium sulfate by the addition of barium chloride. The precipitation is carried out near the boiling temperatutre, and after a period of digestion, the precipiate is filtered, washed with water until free of chloride, ignited or dried, and weighed as barium sulfate. |
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Scope and Application
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This method determines sulfate in water. |
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Applicable Concentration Range
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>10 mg/L |
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Interferences
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(A) High results: High results can be caused by suspended matter, silica, BaCl2 precipitant, nitrate, sulfite, and occluded mother liquor in the precipitate. (B) Low results: Low results can be caused by alkali metal sulfates, particularly alkali hydrogen sulfates. |
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Quality Control Requirements
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General quality control procedures are provided in Section 4020 of Standard Methods. |
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Sample Handling
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Refrigerate. |
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Maximum Holding Time
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28 days. |
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Relative Cost
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Less than $50 |
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Sample Preparation Methods
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