EL3: Electrons

EL3: Electrons

1. As we know, the first shell can only hold 2 electrons

   • Followed by the second and third shells only holding 8
     • Followed by the fourth and fifth shells holding 18

2. Sub-shells of electrons

   • There are s, p, d and f sub-shells
   • Shell one has one s-sub-shell
     • Shell two has two sub-shells s and p
       • Shell three has three sub-shells s, p and d

3. Atomic orbitals

   • The sub-shells are further divided into atomic orbitals
     • An s-sub-shell always contains one s-orbital
       • A p-sub-shell always contains three p-orbitals
         • A d-sub-shell always contains five d-orbitals
         • Shaped in a dumbell shape
       • Shaped in a spherical shape
     • Each orbital can hold a maximum of two electrons

4. Writing electronic configurations

   • We write 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d10
     • The first number represents what shell it is
     • The letter states what sub-shell it is
     • The superscript number states how many electrons in all the orbitals

Images and files in the map