Chapter 5

• What is the shape of a molecule with 2 electron pair?

  Linear

  • bond angle = 180
  • BeCl2
• What is the shape of a molecule with 3 electron pairs?

  Trigonal planar

  • bond angle = 120
  • BF3
• What is the shape of a molecule with 4 electron pairs?

  Tetrahedral

  • bond angle =109.5
  • CH4
• What is the shape of a molecule with 5 electron pairs?

  Trigonal bipyramidal

  • bond angles = 90, 120
  • PF5
• What is the shape of a molecule with 6 electron pairs?

  Octahedral

  • bond angle = 90
  • SF6
• Define nuclear attraction?


  Attraction of the nucleus for the electrons in the atom.
• Electrons?


  -have a certain quanta of energy (amount)

  • do not orbit the nucleus
  • electrons further from the nucleus contain more energy
• Electron shell?


  Energy levels get closer together at higher levels

  Energy increases as shell number increases

  Electrons can move between energy levels by absorbing or emitting energy equal to the difference in the energy between the two levels
• Atomic orbitals?


  A region of space around the nucleus that can hold up to 2 electrons, with opposite spins

  • different orbitals = s, p, d ,f
  • each orbital has a different shape
  • each orbital can hold up to 2 electrons
• S-orbitals?


  Spherical shape

  • each electron from n=1 upwards contains 1s orbital
  • the greater the shell number, the greater the radius of the s-orbital
• P-orbitals?


  Dumbell shaped

  • 3 p-orbitals per shell - all perpendicular to each other
  • the greater the shell number the further it is from the nucleus
  • each electron shell from n=2 upwards has 3 p-orbitals
• D-orbitals?


  -each shell from n=3 upwards contains 5 d-orbitals

  • higher energy = larger shape
  • max = 10 electons
• F-orbitals?


  -each electron shell from n=4 upwards contains 7 f-orbitals

  • max = 14 electrons
• What is a subshell?


  Orbitals of the same, group together
• Rules to filling the atomic orbitals?

  Filling lowest upwards

  Each orbital can hold up to 2 electrons

  Electrons repel each other and have a property of up/down spin

  Orbitals of the same energy are filled individually before pairing (sitting on the bus rule)