1. Structure of an Atom

2. The Three subatomic particles of an atom: Proton Neutron Electron

3. Structure of an Atom Nucleus: The positively charged center or core of the Atom. Contains MOST of the mass of the Atom.

4. What’s inside the Nucleus: Protons - One of two subatomic particles of an atom found in the nucleus –Relative Mass = 1 –Electrical Charge = (+) Positive

5. Neutrons - One of two subatomic particles of an atom found in the nucleus –Relative Mass = 1 –Electrical Charge = (0) Neutral What’s inside the Nucleus:

6. Electron Cloud: A Region that surrounds the nucleus of an atom in which the electrons are free to move around.

7. What’s found in the Electron Cloud: Electrons - Subatomic particles of an atom that are found moving around in the Electron Cloud. –Relative Mass = 0 –Electrical Charge = (-) Negative

8. All atoms as a whole have a neutral Electrical Charge. How can this be? The # of Protons = the # Electrons.

9. Model of an Atom + 0 - ProtonNucleusNeutron Electron Electron Cloud