1. Ch. 8-3 I
Bonding Theories
Covalent Bonding

2. VSEPR Theory Used to explain 3D shape of molecules
Valence-shell electron-pair repulsion theory
Used to explain 3D shape of molecules

3. VSEPR Theory
Repulsion between electron pairs causes molecular shapes to adjust so that the valence-electron pairs stay as far apart as possible

4. VSEPR Theory C H

5. VSEPR Theory

6. VSEPR Theory
Unshared pairs must be accounted for while predicting shapes
Alter remaining bond angles as they are pulled closer to the nucleus (due to only one nucleus “pulling” on them, instead of two as in a bond)

7. VSEPR Theory
Unshared pairs must be accounted for while predicting shapes

8. VSEPR Theory
Unshared pairs must be accounted for while predicting shapes
Each additional unshared pair causes increased change

9. VSEPR Theory
Unshared pairs must be accounted for while predicting shapes

10. VSEPR Theory
3D shape is dependent on number of electron domains (groups)
Domain –
Use the AXE method (each atom will have it’s own value)
A – Atom of interest (Central Atom)
X – Bonding groups
E – Unshared pairs
Location of a lone pair or bond around an atom
(is independent of whether it is a single, double, or triple bond)
Sum equals number of domains

11. VSEPR Theory
3D shape is dependent on number of electron domains (groups)
Each previous example has 4 domains
CO2 has only 2 domains

12. VSEPR Theory
p.233 in textbook