The document defines the basic particles that make up atoms including protons, neutrons, and electrons. Protons have a positive charge and are located in the nucleus along with neutrons which have no charge. Electrons have a negative charge and orbit the nucleus in electron clouds. Atoms are the smallest units of matter and consist of a nucleus surrounded by electrons.

1. Particles + -

2. Particles The smallest pieces of MATTER

3. Protons + Positive Charge Located in Nucleus Mass = 1 amu + +

4. Neutrons 0 Neutral Charge Located in Nucleus Mass = 1 amu

5. Electrons - Negative Charge Located in Electron Cloud Almost ZERO Mass - -

6. amu = Atomic Mass Unit Valence e- = Electrons on the OUTSIDE of the Electron Cloud More Valence e- = More Reactive

7. Atoms Atoms are the smallest complete pieces of matter

8. Atomic Structure Electron Proton Neutron Electron Cloud Nucleus

10. LINKS Atoms Brain POP Atomic Model Brain POP