Introduction to the electron configuration designation for the quantum numbers of electrons


The chemist disignate for the electrons only:

• the principal quantum number
• The subsidiary quantum number:

  Subsidiary quantum number	letter designation
  0	s
  1	p
  2	d
  3	f

To disignate all the electron in an atom, one lists first the principal quantum number followed by the letter for the subsidiary quantum number with an exponent for the number of electrons that have those two quantum numbers:

Examples:

He has two electrons:	1s2
Be has four electrons:	1s22s2
N has seven electrons:	1s22s22p3
Ca has 20 electrons:	1s22s22p63s2 3p64s2