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Pure Appl. Chem., Vol. 70, No. 1, pp. 237-257, 1998.


History of the recommended atomic-weight values*

Thorium

Z
E
Year
Ar(E)
U[Ar(E)]
D[Ar(E)]
D[Ar(E)]
U[Ar(E)]
90 Th 1882 233.95 0.1 1.9 19
1894 232.6 0.3 0.56 1.9
1896 232.63 0.03 0.59 20
1900 232.6 0.3 0.56 1.9
1903 232.5 0.3 0.46 1.5
1909 232.42 0.03 0.38 13
1911 232.4 0.3 0.36 1.2
1919 232.15 0.03 0.11 3.7
1931 232.12 0.03 0.082 2.7
1953 231.98 0.03 -0.058 -1.9
1961 232.038 0.003 -0.0001 -0.033
1969 232.0381 0.0001

> Return to list or table of elements

Ref. History of the recommended atomic-weight values from 1882 to 1997: a comparison of differences from current values to the estimated uncertainties of earlier values, Pure Appl. Chem., Vol. 70, No. 1, pp. 237-257, 1998.

Page last modified 7 June 2000
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