1. Intro movie

2. Intermolecular Forces betweenAttractive forces between molecules Determine phase at room temperature 3 kinds: –Dispersion –Dipole-dipole –Hydrogen bonding withinMuch weaker than forces within a molecule

3. Intramolecular Force – forces within a molecule A chemical bond is the force that holds two atoms together Due to electrostatic forces (charges) Bonding: 1. ionic bonding: 1. ionic bonding: metals and nonmetals 2. covalent bonding: 2. covalent bonding: nonmetals and nonmetals 3. metallic bonding: 3. metallic bonding: metals and metals

4. So why do atoms bond?! Atoms attain a stable valence electron configuration by bonding with atoms. All atoms want to be like Noble Gases because they have a stable valance electron configuration (a full octet)

5. What Noble Gases tell us: notDo not form compounds under ordinary conditions stable –= extremely stable 8 valence electrons = great stability8 valence electrons = great stability –also low energy!

6. Octet Rule: Why Bonds Form noble gasGoal: achieve noble gas electron config. - want 8 valence electrons (H wants a total of 2) Why: Low energy, high stability state How: Atoms form bonds by: gaining losing, or sharing electrons

7. Energy & Stability High Energy means Low Stability Low Energy means High Stability

8. Stability in Chemical Systems If it exists, its stable! Of course, some things are more stable than others!

9. Quick Quiz Elements in the same column have the same ____________________________. number of valence electrons Elements with the same number of valence electrons have similar _____________________________. chemical properties

10. 3 Types of Bonding IonicIonic: electrons are transferred CovalentCovalent: electrons are shared MetallicMetallic: “sea of mobile electrons”