# What is the electron configuration for F?

Well, for $\text{fluorine}$, $Z = 9. . .$
$1 {s}^{2} 2 {s}^{2} 2 {p}^{5}$...the fact that fluorine ALMOST has a full valence shell, i.e. equivalent to that of neon, $1 {s}^{2} 2 {s}^{2} 2 {p}^{6}$, makes fluorine the most reactive element on the Periodic Table...