Nuclear charge = number of protons in the nucleus
Use the atomic number to find the nuclear charge
Nuclear charge = +Z
For a neutral atom, nuclear charge = number of electrons only if the atom is neutral and the element is identified by atomic number
For ions, nuclear charge does not change with charge; it still equals the number of protons
Example: hydrogen = +1
Example: carbon = +6
Example: oxygen = +8
Example: sodium = +11