The shells are present outside the nucleus of an atom, where the electrons are said to be present. The atom of Mg²⁺ has a full outer shell. Thus, option C is correct.
What is an atom?
An atom is the unit of the molecule that comprises sub-atomic particles, electrons, protons, and neutrons. The electron is present in the shells of the atom and can be completely filled by forming the bonds.
Magnesium has atomic number 12 and its electronic configuration is given as 2, 8, 2. When it gives or donates 2 electrons it becomes positively charged and now has completely filled outer shell.
Therefore, option C. Mg²⁺ has a full outer shell.
Learn more about atoms here:
https://brainly.com/question/13545542
#SPJ1
