Question

Which of the following atoms has a full outer shell?
A. Ca
B. Li-1
C. Mg+2
D. N-2

Answer 1

Magnesium ( Mg+² ) has a full outer shell .

Reason:-

K and L shells of an atom are full , then it will have a total of 2 + 8 = 10 electrons in it . We know that magnesium has 12 electrons in it . Magnesium having 2 free electrons.