EPA-NERL: 215.2: Calcium by Titrimetry
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Official Method Name
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Calcium (Titrimetric, EDTA) |
|---|---|
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Current Revision
| Issued 1974; Editorial Revision 1978 |
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Media
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WATER |
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Instrumentation
|
Titration |
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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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Calcium ion is sequestered upon the addition of disodium dihydrogen ethylenediamine tetraacetate (EDTA). The titration end point is detected by means of an indicator which combines with calcium only. |
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Scope and Application
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This method determines calcium in drinking and surface waters, domestic and industrial wastes. |
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Applicable Concentration Range
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0.5-25 mg/L as Ca(CO)3. |
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Interferences
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Metals: Strontium and barium interfere in excess of 30 mg/L and may cause an indistinct end point. Magnesium can also interfere, but is eliminated by raising the pH to 12-13 to precipitate magnesium hydroxide. |
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Quality Control Requirements
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None. |
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Sample Handling
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None. |
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Maximum Holding Time
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6 months (MCAWW, Table 1). |
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Relative Cost
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Less than $50 |
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Sample Preparation Methods
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None. |
