1. Metallic Bonding

2. What is a metallic bond? O bond found in metals O holds metal atoms together very strongly

3. Electrons O Localized: O Electrons hang out in a local area O Restricted to an atom/ion or shared between atoms O Delocalized: O Electrons not attached to a particular area O Electrons are able to travel and move among atoms

4. Metallic Bonds O Formed between atoms of metallic elements O Between atoms on left side of periodic table O Electronegativities are approximately equal O Electron cloud around atoms, delocalized electrons O Valence electrons shared among multiple atoms, “neighbors” O Electrons move through the whole metal, can jump between energy levels to create conduction bands. O Enables the conduction of electricity

5. Metallic Bonds (cont.) O Delocalized electrons result in good electrical and thermal conductors O 3-D network of metal ions and electron sea O Examples; Na, Fe, Al, Au, Co

6. Properties of Metals Attributed to Metallic Bonding (Band Theory) O Conductivity O Malleability O Ductility O Shiny appearance

7. Metallic Bond, A Sea of Electrons

8. Metallic Bonds: Mellow dogs with plenty of bones to go around.

9. Alloys O Metallic compounds with 2 different elements O Enhances metallic characteristics O Ex. Sterling silver (approx. 92-93%Ag, other metal—Cu) O Brass (Cu and Zn) O Stainless steel (contains chromium, prevents corrosion, structural component)

11. What is the point of chemical bonding? O Physical/chemical properties vary based on O Structure O Bond type O Ionic Bonds O High melting point O High boiling point O Covalent Bonds O Lower melting point O Lower boiling point

12. Homework O Test Study Guide O Read pp. 1004-1007