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1.2 Isotopes

Part of Atoms, Isotopes, and Ions in Honors Chemistry. Read the opening section, then create a free account for the full interactive lesson, practice, and progress tracking.

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Atomic Number

An atom’s atomic number signifies the number of protons in the nucleus of an atom. A different number of protons means a different atom. For example, hydrogen only has 1 proton while Oxygen has 16.

In this unit

3 lessons

  1. 1.1Atomic StructurePreview lesson
  2. 1.2IsotopesThis lesson
  3. 1.3IonsPreview lesson

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