# What is the total number of electrons in a superoxide ion, O_2^-?

Well, we start with an oxygen molecule, ${O}_{2}$.......
Now dioxygen, $O = O$, has 16 electrons. How do we know this? For oxygen, $Z = 8$, and thus neutral ${O}_{2}$ necessarily has $\text{16 electrons}$. And thus $\text{superoxide}$ MUST have $\text{17 electrons....}$