# How many valence electrons dose Ra have?

Radium is in group 2/IIA, and all of the elements in that group have two valence electrons. You can also determine the number of valence electrons from its electron configuration, which is $\text{[Rn]7s"^2}$. For the representative elements, groups 1/IA, 2/IIA, and groups 13/IIIA-18/VIIIA, valence electrons are the electrons in the $\text{s}$ and $\text{p}$ sublevels in the highest energy level, in this case $7$.