* Protons define the element: The number of protons (28 in this case) is the atomic number, which uniquely identifies an element. Element number 28 is Nickel (Ni).

* Mass number and neutrons: The mass number (60) is the sum of protons and neutrons. Since we know there are 28 protons, we can calculate the number of neutrons: 60 - 28 = 32 neutrons.

Therefore, the atom is Nickel-60 (⁶⁰Ni), which has 28 protons and 32 neutrons.