What is the purpose of writing electron configuration vs just using the number of electrons off of the periodic table. I know it can be used to determine the number of electrons in each energy level, and therefore, the number of valence electrons. Is there anything else? The number of valence electrons can be found from the periodic table, so why go through that process?

  • $\begingroup$ By long and short hand, do you mean "1s2 2s2 2p6 3s2 3p6" versus "[Ne] 3s2 3p6"? $\endgroup$ – pentavalentcarbon Nov 2 '17 at 18:58
  • $\begingroup$ Yes, using the noble gases $\endgroup$ – Sarah Nov 2 '17 at 19:45
  • $\begingroup$ atomic electron configurations are used in systematics of atomic spectral lines, like in atomic-emission and X-ray spectroscopy. $\endgroup$ – permeakra Nov 2 '17 at 20:24
  • $\begingroup$ I feel your logic is somehow deeply flawed. Configuration is among best forms of description of atoms, which are available. It's like asking for what is knowledge of boiling point of water used, or of color of sky. $\endgroup$ – Mithoron Nov 2 '17 at 22:55

Well, it's almost always this way.

  1. If you know the atomic electronic configuration, you know how many electrons an element has.

  2. If you know how many electrons it has, you'll know how many it needs to have a stable configuration (usually octet).

  3. If you know how many it electrons it needs, you'll know how it reacts with other species.

  4. If you know how substances react, you can predict the reactions involving this substance.

  5. If you know reactions involving this substance, you can either discover a new reaction (knowledge of new reactions makes synthesis easier) or you could invent an unknown compound with interesting properties, which may have its own special uses.

| improve this answer | |
  • $\begingroup$ Is there a benefit to electron configuration specifically vs finding that information from the periodic table. Bohr model, etc? Does knowing the electrons in specific energy levels give us additional info? $\endgroup$ – Sarah Nov 2 '17 at 18:43
  • $\begingroup$ @Sarah Yup, it definitely does. Knowing energy levels can be a big factor in deciding if a reaction is feasible under some conditions or not. In some cases, we can even predict the color of a molecule by knowing the wavelength of light needed to excite electrons within energy bands in a molecule. $\endgroup$ – Pritt says Reinstate Monica Nov 3 '17 at 3:47

Not the answer you're looking for? Browse other questions tagged or ask your own question.