6-5 Molecular Geometry

VSEPR Theory

• VSEPR theory – states that repulsion between the sets of valence-level electrons surrounding an atom causes these sets to be oriented as far apart as possible

• Shared pairs are oriented as far away from each other as possible

VSEPR Theory

• VSEPR and Unshared Electron Pairs – lone pair occupies space around the atom just as the bonding pairs do

Hybridization

• Hybridization – the mixing of two or more atomic orbitals of similar energies on the same atom to produce new orbitals of equal energies

• What does hybridization mean???

Ex. of hybridization…

• Methane, CH4,

C __ __ __ __ __ 1s 2s 2p

• How does carbon form four equivalent, tetrahedrally arranged covalent bonds by orbital overlap with four other atoms?

Ex. of hybridization…

• Methane, CH4, undergoes hybridization

C __ __ __ __ __ 1s sp3

• Hybrid orbitals- orbitals of equal energy produced by the combination of two or more orbitals on the same atom

Intermolecular Forces

• Intermolecular forces – the forces of attraction between molecules

• vary in strength but are generally weaker than bonds that join atoms in molecules, ions in ionic compounds, or metal atoms in solid metals

Hydrogen Bonding

• Hydrogen bonding- hydrogen atom is bonded to a highly electronegative atom, that group is attracted to other nearby molecules

• Hydrogen bonds are usually represented by dotted lines connecting the hydrogen-bonded hydrogen