1. V alence S hell E lectron P air R epulsion Theory Planar triangular Tetrahedral Trigonal pyramidal Bent

2. VSEPR theory assumes that the shape of a molecule is determined by the repulsion of electron pairs. Molecular Shape

3. VSEPR Theory Based on Electron Dot (Lewis structures) Theory predicts shapes of compounds abbreviated VSEPR VSEPR (pronounced “vesper”) stands for Valence Shell Electron Pair Repulsion VSEPR predicts shapes based on electron pairs repelling (in bonds or by themselves) Electrons around central nucleus repel each other. So, structures have atoms maximally spread out

4. VSEPR overview Each shape has a name (you will have to know these ) Names of Shapes: tetrahedral trigonal pyramidal Bent Linear trigonal planar

5. Triangular PlanarTetrahedral Trigonal pyramidal Linear Bent Models

6. methane, CH 4 Bonds are all evenly spaced electrons 109.5° Tetrahedral

7. Less repulsion between the bonding pairs of electrons.. ammonia NH 3.. Trigonal Pyramidal

8. .. 109.5° (109.5°) 109.5° (107°) 109.5° (105°) water, H 2 O

9. ..

10. Bent 2 unshared pairs of e’s at top of O repel bonds and force them to bend

11. molecular geometry. H 2 CO

12. molecular geometry. H 2 CO

13. tetrahedral Methane (CH 4 ) simple hydrocarbon. Shape is not planar but tetrahedral.

14. C H H H H tetrahedral

15. MoleculeLewis StructureNumber of electron pairs CH 4 NH 3 SHAPE Tetrahedral Trigonal Pyramidal 4 4 (3 shared 1 lone pair)

16. MoleculeLewis StructureNumber of electron pairs H2OH2O CO 2 SHAPE Bent 4 (2 shared 2 lone pairs) 4 Linear

17. MoleculeLewis StructureNumber of electron pairs BeCl 2 BF 3 SHAPE 2 3 Linear Trigonal Planar

18. SL Content

19. HL Content