Question

What's the most stable electron configuration?

Answer 1

The most stable electron configuration is that of a noble gas, due to the fact that its valence shell is filled. For helium, that means two valence electrons (a duet) in the `"1s"` sublevel, and for the rest it means eight valence electrons (an octet) in the outermost `"s"` and `"p"` sublevels.

Atoms undergo ionic and covalent bonding in order to achieve a noble gas configuration, which makes them stable.