1. Reading the Periodic Table: Element Squares

2. Atomic Structure Nucleus Electron Cloud

3. Atomic Structure Electrons Protons Neutrons

4. Protons In the nucleus A Positive(+) charge Mass = 1 a.m.u Determine the element Determine the atomic number In the nucleus A Positive(+) charge Mass = 1 a.m.u Determine the element Determine the atomic number

5. Protons

6. Protons and P. Table Atomic # = a whole # Atomic # = # protons

7. Electrons In electron cloud In Unbound atom are equal in number to protons Negatively charged Mass=1/1800 amu In electron cloud In Unbound atom are equal in number to protons Negatively charged Mass=1/1800 amu e e

8. Electrons and P. Table The atomic # = # protons Atoms not involved in bonds have the same number of electrons as protons. Atomic # can be used to Infer the number of electrons

9. Neutrons In the nucleus No charge (neutral) Mass = 1 a.m.u. “glue” nucleus together In the nucleus No charge (neutral) Mass = 1 a.m.u. “glue” nucleus together

10. Neutrons and P. Table All the mass of an atom Is found in the nucleus Only protons and neutrons considered to have mass Calculate # neutrons from Atomic mass

11. Neutrons and P. Table Atomic mass - Atomic # = # neutrons 1.Round atomic mass to nearest whole number Ex. # neutrons in helium Atomic mass = 4.006 =4 Atomic # = 2 4 - 2 = 2 neutrons

12. Test yourself Element name? Gold # protons? 79 # electrons? 79 # neutrons? 118 Element name? Gold # protons? 79 # electrons? 79 # neutrons? 118

14. Families Columns = Families (or groups) Family members share common properties

15. Periods Period = Row Row number = # energy levels ( shells) Period = Row Row number = # energy levels ( shells)