# How many neutrons are there in a single Fe^(2+) atom?

The oxidation state of iron, given as $F {e}^{2 +}$, is there to distract you. For $F e$, $Z$, the atomic number, $= 26$. Thus there are 26 positively charged, massive particles within ALL iron nuclei. This property defines the element as iron. The most common isotope of iron is ""^56Fe, approx. 90% abundant.
Since the mass of the iron nuclide is $56$, there must be $56 - 26 = 30$ neutrons, $30$ massive, neutral particles in this iron nucleus.