nLab atomic number




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The atomic number of a chemical element is the number of protons in any atomic nuclei of this element.

For instance carbon has atomic number 6.

The periodic table of chemical elements organizes them by their atomic number, together with other properties.

The corresponding number of neutrons on the nucleus tends to be close to the number of protons, hence to the atomic number of the element, but need not equal it and my differ considerably for heavy elements. These variants of neutron number for given atomic number specify the isotopes of the chemical element.


See also

Speculative analogy to characteristic classes of complex surfaces (different from but inspired by Skyrmion models for atomic nuclei):

Created on January 24, 2019 at 08:17:03. See the history of this page for a list of all contributions to it.