Physical Science Unit Vocabulary List

The number of neutrons in an isotope may be determined by subtracting the number of protons (atomic number) from the mass number. #n0 = A - Z. If working with the element, the atomic mass may be rounded to a whole number and used as a mass number. 9. An atomic nucleus contains 6 protons and 6 neutrons. About the nucleus move 2 electrons in the ... ................
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