Question

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

Answer 1

Generally there are 30 neutrons in an iron nucleus.

Explanation:

The oxidation state of iron, given as `Fe^(2+)`, is there to distract you. For `Fe`, `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.