Other pages in this series (88)
Atomic weight
Se · selenium
셀레늄
Takeaway
- Recommended or revised 5 times between 1902 and 2024 (first record 1902, latest revision 2013).
- The one revision whose previous recommendation had an uncertainty kept the new value inside the previous (expanded) range.
- The current standard atomic weight is 78.971(8) (recommended in 2013).
| Yearyear of the recommendation | Value (as printed)as printed in CIAAW's table; digits in parentheses are the uncertainty (expanded range) in the last digits | Notationvalue(uncertainty), interval or no uncertainty | Scalebefore 1961 oxygen = 16, from 1961 ¹²C = 12 | Value, ¹²C scalepre-1961 values multiplied by 15.9994/16 | z vs previous(new − previous) ÷ previous uncertainty | ReportDOI of the CIAAW report |
|---|---|---|---|---|---|---|
| 1902 | 79.1 | no uncertainty | O=16 | 79.09703375 | 10.1007/BF01370337 | |
| 1903 | 79.2 | no uncertainty | O=16 | 79.19703 | 10.1021/ja02003a001 | |
| 1934 | 78.96 | no uncertainty | O=16 | 78.957039 | 10.1039/JR9340000499 | |
| 1969 | 78.96(3) | value(uncertainty) | 12C=12 | 78.96 | 10.1351/pac197021010091 | |
| 2013 | 78.971(8) | value(uncertainty) | 12C=12 | 78.971 | 0.367 | 10.1515/pac-2015-0305 |
Source: Standard atomic weights © IUPAC/CIAAW 2016–2024. Commission on Isotopic Abundances and Atomic Weights, Historical changes of standard atomic weights (compiled by J. Meija), https://www.ciaaw.org/historical-atomic-weights.htm