The electron configuration of 22X²+ ion is?
A. 1s2 2s22p6 3s2 3p6 4s2 3d2
B. 1s2 2s22p6 3s2 3p6 4s2 3d1
C. 1s2 2s22p6 3s2 3p6
D. 1s2 2s22p6 3s2 3p6 4s2
Correct Answer:
Option D – 1s2 2s22p6 3s2 3p6 4s2
Explanation
22X²+ has 22 electrons but has been ionized to 2+ by giving off 2 electrons. Hence, the ion 22X²+ has 20 electrons.
The electronic configuration = 1s2 2s22p6 3s2 3p6 4s2