Question

what is the total number of electrons needed to fill the third main energy level?
o 18
o 32
o 8
o 2

Explanation:

Step1: Recall the formula for the number of electrons in a main energy level

The formula to calculate the number of electrons in a main energy level \(n\) is \(2n^{2}\).

Step2: Substitute \(n = 3\) into the formula

When \(n=3\), we have \(2\times3^{2}=2\times9 = 18\).

Answer:

18