Chapter 2 – Atoms, Ions, and the Periodic Table

From the periodic table we find that phosphorus’ atomic number is 15 so there are 15 protons. Since the mass number is 32, the number of neutrons is Z = A – N = 32 – 15 = 17. 2.41 The isotope symbol takes the form where the mass number is the neutrons plus protons and the charge is determined by the protons and electrons. ................
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