1. The atom

2. Electron Clouds Major energy level Maximum number of electrons
K 2 electrons
L 8 electrons
M 18 electrons
N 32 electrons
O 32 electrons
P 18 electrons
Q 2 electrons

3. Atomic Number Atomic Number Number of Protons in the Nucleus
Atomic Mass Average weight of an element’s atom

4. Periodic Table

5. Hydrogen

6. Carbon

7. Oxygen

8. Water Molecule

9. Carbon Dioxide Molecule

10. Sodium atom

11. Chloride atom

12. Sodium Chloride molecule

13. Sodium Chloride in Water

14. Isotopes Atoms of the same element that have different numbers of neutrons in the nucleus

15. Isotopes of Carbon Carbon 12 6 protons, 6 neutrons, 6 electrons
Carbon protons, 8 neutrons, 6 electrons Radioactive