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Four-place table of standard atomic weight values of hydrogen through uranium compared since 1961

Published by U.S. Geological Survey | Department of the Interior | Metadata Last Checked: January 27, 2026 | Last Modified: 2022-09-08T00:00:00Z
Four-figure standard atomic weights of the chemical elements are shown for 1961, 1975, 1983, 2007, 2009, 2011, 2013, 2015, and the current value for 2016. Values between 1975 and 2015 are only shown when there is a change in value with respect to the previous column.

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