Molecular Structure II Molecular Geometry I II III

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– Molecular Structure II. Molecular Geometry I II III

– Molecular Structure II. Molecular Geometry I II III

A. VSEPR Theory n Valence Shell Electron Pair Repulsion Theory n Electron pairs orient

A. VSEPR Theory n Valence Shell Electron Pair Repulsion Theory n Electron pairs orient themselves in order to minimize repulsive forces. I II III

A. VSEPR Theory n Types of e- Pairs · Bonding pairs - form bonds

A. VSEPR Theory n Types of e- Pairs · Bonding pairs - form bonds · Lone pairs - nonbonding e- Lone pairs repel more strongly than bonding pairs!!! I II III

A. VSEPR Theory n Lone pairs reduce the bond angle between atoms. Bond Angle

A. VSEPR Theory n Lone pairs reduce the bond angle between atoms. Bond Angle I II III

B. Determining Molecular Shape n Draw the Lewis Diagram. n Tally up e- pairs

B. Determining Molecular Shape n Draw the Lewis Diagram. n Tally up e- pairs on central atom. · double/triple bonds = ONE pair n Shape is determined by the # of bonding pairs and lone pairs. Know the 8 common shapes & their bond angles! I II III

C. Common Molecular Shapes 2 total 2 bond 0 lone Be. H 2 LINEAR

C. Common Molecular Shapes 2 total 2 bond 0 lone Be. H 2 LINEAR 180° I II III

C. Common Molecular Shapes 3 total 3 bond 0 lone BF 3 TRIGONAL PLANAR

C. Common Molecular Shapes 3 total 3 bond 0 lone BF 3 TRIGONAL PLANAR 120° I II III

C. Common Molecular Shapes 3 total 2 bond 1 lone SO 2 BENT <120°I

C. Common Molecular Shapes 3 total 2 bond 1 lone SO 2 BENT <120°I II III

C. Common Molecular Shapes 4 total 4 bond 0 lone CH 4 TETRAHEDRAL 109.

C. Common Molecular Shapes 4 total 4 bond 0 lone CH 4 TETRAHEDRAL 109. 5° I II III

C. Common Molecular Shapes 4 total 3 bond 1 lone NH 3 TRIGONAL PYRAMIDAL

C. Common Molecular Shapes 4 total 3 bond 1 lone NH 3 TRIGONAL PYRAMIDAL 107° I II III

C. Common Molecular Shapes 4 total 2 bond 2 lone H 2 O BENT

C. Common Molecular Shapes 4 total 2 bond 2 lone H 2 O BENT 104. 5° I II III

C. Common Molecular Shapes 5 total 5 bond 0 lone PCl 5 TRIGONAL BIPYRAMIDAL

C. Common Molecular Shapes 5 total 5 bond 0 lone PCl 5 TRIGONAL BIPYRAMIDAL 120°/90° I II III

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

C. Common Molecular Shapes 6 total 6 bond 0 lone SF 6 OCTAHEDRAL 90° I II III

D. Examples n PF 3 4 total 3 bond 1 lone F P F

D. Examples n PF 3 4 total 3 bond 1 lone F P F F TRIGONAL PYRAMIDAL 107° I II III

D. Examples n CO 2 2 total 2 bond 0 lone O C O

D. Examples n CO 2 2 total 2 bond 0 lone O C O LINEAR 180° I II III