Question

how is this model useful?
○ it shows how electrons are distributed in the shells of an iron atom.
○ it shows how electrons are distributed in the shells of a cobalt atom.
○ it shows how orbitals are distributed in the shells of an iron atom.
○ it shows how orbitals are distributed in the shells of a cobalt atom.

Explanation:

The model shown is a Bohr - like model of an atom, which represents the distribution of electrons in electron shells (not orbitals, as orbitals are part of the quantum mechanical model). Iron has an atomic number of 26, and the electron configuration can be visualized in such a shell - based model. Cobalt has an atomic number of 27, so the electron count would be different. This model shows electron distribution in shells, and for iron, this model is useful to show how electrons are distributed in its shells. So the correct option is the one that says it shows how electrons are distributed in the shells of an iron atom.

Answer:

It shows how electrons are distributed in the shells of an iron atom.