Standard atomic weights

"The atomic mass, ma, of an unbound neutral atom of carbon-12, ma(12C), in its nuclear and electronic ground states is 12 Da exactly, where Da is the symbol for unified atomic mass unit. The atomic mass of 12C is 12 Da, and the atomic weight of 12C is 12 exactly. All other atomic weight values are ratios to the 12C standard value and thus are dimensionless numbers."
Image showing periodicity of the chemical elements for standard atomic weights in a periodic table cityscape style.
Image showing periodicity of the chemical elements for standard atomic weights in a periodic table cityscape style.
Image showing periodicity of the chemical elements for standard atomic weights in a periodic table heatscape style.
Image showing periodicity of the chemical elements for standard atomic weights in a periodic table heatscape style.
Image showing periodicity of the chemical elements for standard atomic weights in a spiral periodic table heatscape style.
Image showing periodicity of the chemical elements for standard atomic weights in a spiral periodic table heatscape style.
Image showing periodicity of the chemical elements for standard atomic weights in a 3D spiral periodic table column style.
Image showing periodicity of the chemical elements for standard atomic weights in a 3D spiral periodic table column style.
Image showing periodicity of the chemical elements for standard atomic weights in a 3D periodic table column style.
Image showing periodicity of the chemical elements for standard atomic weights in a 3D periodic table column style.

Units

atomic mass units

Notes

Literature sources

  1. T. Prohaska, J. Irrgeher, J. Benefield, J.K. Böhlke, L.A. Chesson, T.B. Coplen, T. Ding, P.J.H. Dunn, M. Gröning, N.E. Holden, H.A.J. Meijer, H. Moossen, A. Possolo, Y. Takahashi, J. Vogl, T. Walczyk, J. Wang, M.E. Wieser, S. Yoneda, X.-K. Zhu, and Juris Meija, Standard atomic weights of the elements 2021 (IUPAC Technical Report), Pure Appl. Chem., 1922, 94, 573-600, https://doi.org/10.1515/pac-2019-0603.
  2. J. Meija, T.B. Coplen, M. Berglund, W.A. Brand, P. De Bièvre, M. Gröning, N.E. Holden, J. Irrgeher, R.D. Loss, T.Walczyk, and T. Prohaska, Atomic weights of the elements 2013 (IUPAC Technical Report), Pure Appl. Chem., 88, 265-291, https://doi.org/10.1515/pac-2015-0305.
Explore the element of your choice through this periodic table.
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*Lanthanoids *
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**Actinoids **
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