Concepts of radiological health / by Samuel C. Ingraham [and others].

  • United States Public Health Service
Date:
1954
Catalogue details

Licence: Public Domain Mark

Credit: Concepts of radiological health / by Samuel C. Ingraham [and others]. Source: Wellcome Collection.

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    The usual atomic state is one of electric neutrality. The number of orbital electrons equals the number of protons in the nucleus and the net negative and net positive charges balance each other, Each atomic number equals the number of protons or of electrons present in the atoms of its chemical element. Therefore, the atomic numbers also represent the total positive or negative atomic electric charges of the elements. Since the neutrons and protons are the heavy atomic component, most of the mass of an atom lies in its nucleus, To review for a moment, atoms are made up of three kinds of subatomic particles: Subatomic Particles vides mee Location charge 4 | Grams Approximate mass units It has become accepted practice to des- Ne / ignate the various elements by symbols a ay (Appendix B). The symbol for hydrogen hea 1634. Atoms containing two nuclear protons and, therefore, two orbital electrons form the next atomic configuration. Atoms of this kind are helium. The symbol for helium is He. Three nuclear protons and three Orbital electrons are in the third kind of atom, lithium. The symbol for lithium is Li. The addition of nuclear protons and peripheral electrons continues step by step up through the ninety-eight elements, Atoms with 92 protons
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