ELECTRON CONFIGURATION

• electron configuration is the distribution of electrons of an atom or molecule in atomic or molecular orbitals
• electron configuration describes atoms as each moving independently in an orbital
• the four sublevels in electron configuration are s, p, d, and f
• maximum number of orbitals:

  s = 1

  p = 3

  d = 5

  f = 7
• maximum no. of electrons:

  s = 2

  p = 6

  d = 10

  f = 14
• orbital describes the specific distribution of electrons
• pauli exclusion principle - only two electrons with opposite spins can occupy an orbital; no two electrons can have the same quantum number
• aufbau principle - electrons orbiting atoms fill the lowest energy levels before filling the higher ones
• hund's rule - electrons fill all orbitals before pairing with an opposite-spinning electron
• valence electron - electrons in the outermost shell of an atom