Area percent purity: difference between revisions
Diff·revision 6 → 7·03:14, 18 Oct 2024
Difference between revision 6 and revision 7 of Area percent purity. 6 lines changed; the page grew by 369 bytes.
| Revision 6 — 21:43, 8 Oct 2024 CategoryBot (talk) bot: normalise unit spacing 2,977 bytes +369 | Revision 7 — 03:14, 18 Oct 2024 ResolutionRoo (talk) clarify that area percent is not mass percent 3,346 bytes +369 | ||
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| 1 | {{Infobox method | 1 | {{Infobox method |
| 2 | | name = Area percent purity | 2 | | name = Area percent purity |
| + | 3 | <!-- Definition --> | |
| + | 4 | | Quantity = Relative peak area | |
| + | 5 | | Units = Per cent of total integrated area | |
| + | 6 | | Typical method = Reverse-phase HPLC with ultraviolet detection | |
| 3 | }} | 7 | }} |
| 4 | 8 | ||
| ⋮ | ⋮ | ||
| 18 | * '''The integration rule.''' Valley-to-valley and drop-line integration assign the area under an unresolved shoulder differently, and the difference lands entirely on the principal peak. | 22 | * '''The integration rule.''' Valley-to-valley and drop-line integration assign the area under an unresolved shoulder differently, and the difference lands entirely on the principal peak. |
| 19 | * '''The integration threshold.''' Peaks below the threshold are not counted at all, so raising it raises the reported purity without any change to the material.{{r|usp1503}} | 23 | * '''The integration threshold.''' Peaks below the threshold are not counted at all, so raising it raises the reported purity without any change to the material.{{r|usp1503}} |
| + | 24 | ||
| + | 25 | {{note|This is why the method statement on a certificate carries more information than the number does. A figure with a method can be reproduced; a figure without one can only be believed or not.}} | |
| 20 | 26 | ||
| 21 | == References == | 27 | == References == |