Shells and Orbitals

Shells and Orbitals

1. Ionisation Energies

   • First Ionisation Energy: Energy required to remove the outer electron from each atom in 1 mole of gaseous to form 1 mole of gaseous 1+ ions.
   • Successive Ionisation Energies: Energy required to remove each electron in turn.
   • Factors
     • Electron Shielding
     • Nuclear Charge
     • Atomic Radius

2. Subshells and Orbitals

   • Subshell: Group of the same type of orbital in the same shell.
   • Orbital: Region around the nucleus where electrons can be found (maximum 2 with opposite spins).
   • Orbital Types
     • s-Orbitals
       • 1 per subshell (2 electrons)
       • From n=1 upwards
       • Spherical shape
     • p-Orbitals
       • 3 per subshell (6 electrons)
       • From n=2 upwards
       • Dumbbell/eggtimer shape
     • d-Orbitals
       • 5 per subshell (10 electrons)
       • From n=3 upwards
     • f-Orbitals
       • 7 per subshell (14 electrons)
       • From n=4 upwards

3. 1S 2S 2P 3S 3P 4S 3D 4P

   • Although it is in the next shell, the 4S subshell is filled before the 3D subshell, as it is a lower energy level. However, when they are both filled, then 3D subhsell is a lower energy level than the 4S subshells, so the 4S are also emptied first.

Images and files in the map