An atom with an atomic number 26 and mass of 58 has how many protons & Neutrons

Protons = 26
Neutrons = 30
Electrons = 26

Protons is the atomic number. In order to balance the charge of the atom, there needs to be the same number of positive subatomic particles (protons) as there is negative (electrons). In this case, the atom is neutral, so there are 26 protons and electrons to balance out the charges. Fe56 is an isotope, and the mass number is 56. The mass number comes from the sum of protons and neutrons. We know that the atomic number (number of protons) is 26. Subtract that from 56 to get the number of neutrons (30). Hope this makes some sense to you.