# Beryllium has how many valence electrons in its last ring?

$\text{Be} : 1 {s}^{2} 2 {s}^{2}$, or using the noble gas shorthand notation,
"Be":["He"]2s^(2)
Valence electrons are defined as the electrons capable of forming chemical bonds with other atoms, and are lcoated in the outermost shell of the atom. As its electron configuration shows, $\text{Be}$ has 2 valence electrons located in the 2s subshell.
These electrons give $\text{Be}$ a +2 oxidation state and the ability to form 2 covalent bonds.