Os · osmium

오스뮴

Takeaway

Recommended or revised 7 times between 1902 and 2024 (first record 1902, latest revision 1991).
The one revision whose previous recommendation had an uncertainty kept the new value inside the previous (expanded) range.
The current standard atomic weight is 190.23(3) (recommended in 1991).

Relative deviation from the current (or last) value, symmetric-log axis. Bars: uncertainty (expanded range); open circles: no uncertainty; orange boxes: intervals.

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	191.0	no uncertainty	O=16	190.9928375		10.1007/BF01370337
1909	190.9	no uncertainty	O=16	190.89284125		10.1021/ja01931a001
1925	190.8	no uncertainty	O=16	190.792845		10.1039/CT9252700913
1934	191.5	no uncertainty	O=16	191.49281875		10.1039/JR9340000499
1938	190.2	no uncertainty	O=16	190.1928675		10.1039/JR9380001101
1969	190.2(1)	value(uncertainty)	12C=12	190.2		10.1351/pac197021010091
1991	190.23(3)	value(uncertainty)	12C=12	190.23	0.300	10.1351/pac199264101519

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