Part 2: Diagraming isotopes In Part 1 we saw the structural differences of atoms of different elements. To see the structural differences of isotopes of the same element we will diagram three isotopes of carbon: Carbon- 12 , Carbon-13, and Carbon-14. (The most common is Carbon- 12, which makes up \( \sim 98.9 \% \) of all carbon elements.) Before diagraming, let's review your knowledge of isotopes. Review: Which particle(s) would you expect to change when diagraming isotopes? Protons Neutrons Electrons

When diagramming isotopes of the same element, **only the number of neutrons changes**. Here's why: - **Protons:** The number of protons defines the element itself. For example, all carbon atoms have **6 protons**. This number remains constant across all isotopes of carbon. - **Electrons:** In a neutral atom, the number of electrons equals the number of protons to balance the charge. Since the number of protons doesn't change, the number of electrons also remains the same in each isotope, assuming the atom is not ionized. - **Neutrons:** This is the part that varies among isotopes. Different isotopes of the same element have different numbers of neutrons. For example: - **Carbon-12:** 6 protons + 6 neutrons - **Carbon-13:** 6 protons + 7 neutrons - **Carbon-14:** 6 protons + 8 neutrons **Summary:** - **Change:** **Neutrons** - **Remain the same:** Protons and Electrons When diagramming isotopes, you only need to adjust the number of neutrons to reflect the specific isotope you are representing.