Molecular Geometry bond length, angle determined experimentally Lewis structures bonding VSEPR geometry Valence Shell Electron Pair Repulsion octahedron 90o bond angles small groups big groups trigonal bipyramid equatorial 120o axial 180o

tetrahedron 109.5o trigonal planar 120o linear 180o geometry apply to Chemistry

.. linear 180o BeCl2 valence e- = 2 + (2 x 7) = 16e- fewer than 8e- Cl two valence pairs on Be bonding e- linear molecule

.. .. linear 180o CO2 valence e- = 4 + (2 x 6) = 16e- C O C O two valence pairs on C ignore double bonds single and double bonds same molecular geometry linear molecular shape linear

.. : .. : .. : trigonal planar 120o SO2 valence e- = 6+ (2 x 6) = 18e- three valence pairs on S two bonding pairs one lone pair molecular geometry trigonal molecular shape bent < 120o

tetrahedral 109.5o CH4 valence e- = 4+ (4 x 1) = 8e- C H four valence pairs on C 109.5o molecular geometry tetrahedral molecular shape tetrahedral

: tetrahedral 109.5o NH3 valence e- = 5+ (3 x 1) = 8e- N H four valence pairs on N three bonding pairs one lone pair molecular geometry tetrahedral molecular shape trigonal pyramid < 109.5o

: tetrahedral 109.5o H2O valence e- = 6+ (2 x 1) = 8e- O H four valence pairs on O two bonding pairs two lone pair molecular geometry tetrahedral molecular shape bent < 109.5o

.. bipyramidal 120o and 1800 PCl5 P Cl valence e- = 5+ (5 x 7) = 40e- five valence pairs on P 180o 90o molecular geometry bipyramidal molecular shape bipyramidal 120o

: .. bipyramidal 120o and 1800 SF4 valence e- = 6+ (4 x 7) = 34e- S F five valence pairs on S four bonding pairs one lone pair < 180o molecular geometry bipyramidal molecular shape seesaw

: .. bipyramidal 120o and 1800 ClF3 valence e- = 7+ (3 x 7) = 28e- Cl five valence pairs on Cl three bonding pairs two lone pair molecular geometry bipyramidal molecular shape T 180o 90o

: .. bipyramidal 120o and 1800 ICl2- valence e- = 7+ (2 x 7) + e- five valence pairs on I two bonding pairs three lone pair on I molecular geometry bipyramidal molecular shape linear

: .. octahedral 90o BrF5 valence e- = 7+ (5 x 7) = 42e- Br F six valence pairs on Br five bonding pairs one lone pair molecular geometry octahedral molecular shape square pyramidal

: .. octahedral 90o XeF4 valence e- = 8+ (4 x 7) = 36e- Xe F six valence pairs on Xe four bonding pairs two lone pair molecular geometry octahedral molecular shape square planar