# What is a noble gas electron configuration?

Aug 24, 2017

Well, helium has a closed shell, $1 {s}^{2}$ electronic configuration....
In order to save some time when writing the configuration of the next element, $L i , Z = 3$, I could write $\left[H e\right] 2 {s}^{1}$; all the reactivity is going to occur in the valence shell.
And likewise for say sulfur, $Z = 16$, which builds on a neon core, we could write, $\left[N e\right] 3 {s}^{2} 3 {p}^{4}$, instead of the long $1 {s}^{2} 2 {s}^{2} 2 {p}^{6} 3 {s}^{2} 3 {s}^{4}$.