If an element has the atomic number 20, what sublevels are present?
It has a p sublevel.
The first energy level has an s; the second energy level has an s and a p; the third energy level has an s, p, and d; the fourth energy level has an s.
It has an s sublevel.
The first energy level has an s; the second and third energy levels have an s and a p; the fourth energy level has an s.
B?
1 answer
look up CALCIUM's electron structure