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2.4 Isotopes

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What Are Isotopes?

Isotopes are atoms of the same element that have the same number of protons but a different number of neutrons in their nucleus. Since the number of protons defines the element, isotopes are still the same element but have different mass numbers. For example, all carbon atoms have 6 protons, but some carbon atoms have 6 neutrons (carbon-12), while others have 7 neutrons (carbon-13) or even 8 neutrons (carbon-14).

In this unit

8 lessons

  1. 2.1Introduction to AtomsPreview lesson
  2. 2.2Subatomic ParticlesPreview lesson
  3. 2.3Atomic Number and Mass NumberPreview lesson
  4. 2.4IsotopesThis lesson
  5. 2.5Overview of the Periodic TablePreview lesson
  6. 2.6Introduction to Electron ArrangementPreview lesson
  7. 2.7Atomic Structure Diagrams & The Bohr ModelPreview lesson
  8. 2.8Ions and ChargesPreview lesson

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