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Atomic number

The atomic number corresponds to the number of protons in the nucleus of an atom of that element. It also corresponds to the number of electrons in the neutral atom.

image showing Atomic number: group 17 periodicity for group 17 chemical elements





Literature sources

  1. International Union of Pure & Applied Chemistry: Commission on the Nomeclature of Inorganic Chemistry, Nomenclature of Inorganic Chemistry Recommendations 2005, Eds. N.G. Connelly, T. Damhus, R.M. Hartshorn, and A.T. Hutton, Royal Sociery of Chemistry, 2005. ISBN-13: 978-0854044382.