1. Molecular Geometry
VSEPR Theory- “Valence- shell, electron-pair repulsion”
states that repulsion between the sets of valence-level electrons surrounding an atom cause these sets to be oriented as far apart as possible.

2. Determining VSEPR H-O-H E2 B B A Determine the VSEPR for H2O
Draw the Lewis Dot
Draw the Structural Formula
Label the central atom as A
Label any atoms attached to the center atom as B
Label any paired electrons on the central atom that are not used in the bond as E
H-O-H E2 B B A
VSEPR AB2E2
Shape Bent (look on chart)

3. Figure 12.5: Charge distribution in the water molecule.
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4. Figure 12.6: Polar water molecules are strongly attracted to positive ions by their negative ends.
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5. Figure 12.12: Molecular structure of methane.
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6. VSEPR Chart VSEPR SHAPE AB or AB2 Linear AB2E Bent AB3 Trigonal-Planar
Tetrahedral
AB3E
Trigonal-Pyramidal
AB2E2
AB5
Trigonal-Bipyramidal
AB6
Octahedral

7. C. Common Molecular Shapes
2 total
2 bond
0 lone
BeH2
LINEAR
180°

8. C. Common Molecular Shapes
3 total
3 bond
0 lone
BF3
TRIGONAL PLANAR
120°

9. C. Common Molecular Shapes
3 total
2 bond
1 lone
SO2
BENT
<120°

10. C. Common Molecular Shapes
4 total
4 bond
0 lone
CH4
TETRAHEDRAL
109.5°

11. C. Common Molecular Shapes
4 total
3 bond
1 lone
NH3
TRIGONAL PYRAMIDAL
107°

12. C. Common Molecular Shapes
4 total
2 bond
2 lone
H2O
BENT
104.5°

13. C. Common Molecular Shapes
5 total
5 bond
0 lone
PCl5
TRIGONAL BIPYRAMIDAL
120°/90°

14. C. Common Molecular Shapes
6 total
6 bond
0 lone
SF6
OCTAHEDRAL
90°

15. D. Examples
F P F F
PF3
4 total
3 bond
1 lone
TRIGONAL PYRAMIDAL
107°

16. D. Examples
O C O
CO2
2 total
2 bond
0 lone
LINEAR
180°

17. Table 12.4
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18. Hybridization-The Blending of Orbitals.
Dipole- is created by equal but opposite charges that are separated by a short distance.
Dipole-Dipole Attractions-Attraction between oppositely charged regions of neighboring molecules.
Hydrogen Bonding- Bonding between hydrogen and more electronegative neighboring atoms such as oxygen and nitrogen. Hydrogen bonding in Kevlar, a strong polymer used in bullet-proof vests.
London Dispersion Forces- The temporary separations of charge that lead to the London force attractions are what attract one nonpolar molecule to its neighbors. London forces increase with the size of the molecules.