Answer:
2
3
Explanation:
To infer the last energy of the given atoms, we need to write their electronic configuration:
For N = 1S² 2S² 2P³
Mg = 1S² 2S² 2P⁶ 3S²
The energy levels are usually designated as;
n = 1
n = 2
n = 3
n =4
For N, the last energy level is 2
Mg, the last energy level is 3
We can also determine this number by the periods the atoms can be found.
