VSEPR & Honors Chemistry: Molecular Shapes, Bond Angles, and Polarity

Linear (AB2)

Shape: Linear; Bond Angle: 180 degrees; Hybridization: sp; Lone Pairs: 0; Example: CO2, BeCl2

Trigonal Planar (AB3)

Shape: Trigonal Planar; Bond Angle: 120 degrees; Hybridization: sp2; Lone Pairs: 0; Example: BF3

Bent (AB2E1)

Shape: Bent; Bond Angle: < 120 degrees; Hybridization: sp2; Lone Pairs: 1; Example: SO2

Tetrahedral (AB4)

Shape: Tetrahedral; Bond Angle: 109.5 degrees; Hybridization: sp3; Lone Pairs: 0; Example: CH4

Trigonal Pyramidal (AB3E1)

Shape: Trigonal Pyramidal; Bond Angle: < 109.5 degrees; Hybridization: sp3; Lone Pairs: 1; Example: NH3

Bent (AB2E2)

Shape: Bent; Bond Angle: << 109.5 degrees; Hybridization: sp3; Lone Pairs: 2; Example: H2O

Trigonal Bipyramidal (AB5)

Shape: Trigonal Bipyramidal; Bond Angle: 90 and 120 degrees; Hybridization: sp3d; Lone Pairs: 0; Example: PCl5

Seesaw (AB4E1)

Shape: Seesaw; Bond Angle: < 90, < 120 degrees; Hybridization: sp3d; Lone Pairs: 1; Example: SF4

T-shaped (AB3E2)

Shape: T-shaped; Bond Angle: < 90 degrees; Hybridization: sp3d; Lone Pairs: 2; Example: ClF3

Linear (AB2E3)

Shape: Linear; Bond Angle: 180 degrees; Hybridization: sp3d; Lone Pairs: 3; Example: XeF2

Octahedral (AB6)

Shape: Octahedral; Bond Angle: 90 degrees; Hybridization: sp3d2; Lone Pairs: 0; Example: SF6

Square Pyramidal (AB5E1)

Shape: Square Pyramidal; Bond Angle: < 90 degrees; Hybridization: sp3d2; Lone Pairs: 1; Example: BrF5

Square Planar (AB4E2)

Shape: Square Planar; Bond Angle: 90 degrees; Hybridization: sp3d2; Lone Pairs: 2; Example: XeF4

Polarity

A molecule is polar if it has a net dipole moment. Depends on bond polarity (electronegativity difference) and molecular symmetry. Symmetrical shapes (like Linear AB2 or Tetrahedral AB4) with identical outer atoms are usually nonpolar.

Resonance

Occurs when one Lewis structure cannot fully describe the bonding. Electrons are delocalized across multiple bonds (like Nitrate or Ozone).

Coordinate Covalent Bond

A bond where one atom provides both electrons for the shared pair.

Intermolecular Forces (IMF)

Forces between molecules (London Dispersion, Dipole-Dipole, Hydrogen Bonding). They determine physical properties like boiling point and melting point.