1. HMSA: Do Now
Get Bond Energy WS stamped if you did not do so before break
Work on Lewis Structures Pre-Lab
Complete first page (front and back) of note packet
Lewis Structures Quest FRI 4/15!

2. VSEPR Theory Valence Shell Electron Pair Repulsion A=Central Atom
X=Bonded Atoms
E=electron pairs (non-bonding) on the central atom

3. Hybridization
Hybridization: combining/mixing of electron orbitals when atoms bond.
The hybridization is determined by the # things around the central atom
The shape is determined by the lone pairs on the central atom

4. Common Hybridizations
# Sets
Orbital Hybridization 2 sp 3
sp2 4
sp3
Note: “sets” refer to bonded atoms as well as lone pairs on the central atom

5. These are REFERENCES…not all the possible hybridizations!

6. sp linear Tetra-hedral sp3 sp2 sp3 sp3 bent AX2 AX4 Trigonal planar
AX3E
pyramidal
sp3
AX2E2
bent

7. sp3
AXE3
linear
All diatomic molecules are linear in shape

8. Polarity of Molecules (Compound)
Comparing electronegativity difference between 2 atoms in a bond, for all bonds in the compound
If there is an electronegativity difference between bonded atoms, and the molecule is asymmetrical, then the compound is polar

9. Polarity of Molecules
If there is an electronegativity difference between bonded atoms, and the molecule is completely symmetrical then the compound is nonpolar

10. Polarity of Molecules
If there is no electronegativity difference between bonded atoms, and the molecule is completely symmetrical then the compound is nonpolar

11. linear no
polar
yes
nonpolar
yes
nonpolar no
polar no
polar
yes
nonpolar

12. Intermolecular Forces (sometimes referred to as “Van der Waals forces”)
Attractive forces between molecules
are NOT BONDS, which is an attraction between 2 atoms
Lots of H2O molecules

13. Types of IMFs: London Dispersion Forces
The weakest intermolecular force
Is the main attractive force between nonpolar molecules
In general, the larger the molecules, the greater the dispersion forces

14. Types of IMFs Dipole-Dipole Forces Stronger than dispersion forces
The main attractive force between polar molecules

15. Types of IMFs
Hydrogen Bonding: is an intermolecular force; it is NOT actually a bond!
The strongest intermolecular force
Only occur in molecules containing Hydrogen AND one of the following: Nitrogen, Oxygen, or Fluorine (NOF)

16. Practice polar yes Hydrogen bonding London dispersion nonpolar no no
Dipole-dipole
polar
yes
Hydrogen bonding
nonpolar no
London dispersion

17. 32
AX4
nonpolar 8
tetrahedral
London
dispersion 24
sp3