* Protons: The number of protons in an atom determines its atomic number. Copper (Cu) has an atomic number of 29, meaning it has 29 protons.
* Electrons: The number of electrons in a neutral atom is equal to the number of protons. Since Cu²⁺ has a +2 charge, it has lost two electrons. Therefore, it has 27 electrons (29 - 2 = 27).
In summary:
* Cu²⁺ has 29 protons and 27 electrons.
