Answer:
4 sublevels are completely filled.
Explanation:
Magnesium is present in group 2.
Its atomic mass is 24 g/mol.
Its atomic number is 12.
It is alkaline earth metal.
Electronic configuration of Mg:
Ma₁₂ = 1s² 2s² 2p⁶ 3s²
From above given electronic configuration we can see all sublevels are completely filled.
The 1st energy level have one sub level (1s) which is completely filled, 2nd energy level have 2 sublevel (2s and 2p) and 3rd energy level have one sublevel (3s) completely filled. So all are completely filled.
