Atomic Weight Change

Ten elements on the Periodic Table of Elements are undergoing revision as scientists revise the way their atomic weights are represented. hydrogen, lithium, boron, carbon, nitrogen, oxygen, silicon, sulfur, chlorine, and thallium will no longer be shown as having a single atomic weight, but rather a range of weights. The new table more accurately reflects fluctuation in the atomic weight of those elements.

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  1. Concatenation — December 31, 2010 @ 10:41 am

    “fluctuation in the atomic weight of those elements”

    I think you will find that atomic weights (actually mass) do not change. However they are an artificial construct of the various ‘relative atomic masses’ of the various isotopes in a sample.

    The change has come about due to modern appreciation of the variations in proportions of various isotopes in samples of elements typically (on Earth) derived from the Earth’s crust.