3.6 the shape of molecules and ions

• each pair of electrons around an atom will repel all other electron pairs, therefore the pairs will take up positions as far apart as possible to minimise repulsion
• electron pairs may be shared pairs or lone pairs
• Shape: linear

  Number of pairs: 2

  Bond angle: 180

  
• Shape: trigonal planar

  Number of pairs: 3

  Bond angles: 120

  
• Shape: tetrahedral

  Number of pairs: 4

  Bond angles: 109.5

  
• Shape: Trigonal bipyramid

  Number of pairs: 5

  Bond angles: 90, 120

  
• Shape: octahedral

  Number of pairs: 6

  Bond angles: 90

  
• Bonds shape: triangular pyramid

  Number of electron pairs: 3

  Number of lone pairs: 1

  Bond angles: 107

  
• shape: bent

  Number of electron pairs: 2

  Number of lone pairs: 2

  Bond angles: 104.5

  
• Shape: square planar

  Number of electron pairs: 4

  Number of lone pairs: 2