Question

in one atom, what is the maximum number of electrons that could have the quantum number of n = 2?

Explanation:

Step1: Recall electron - shell formula

The number of electrons in a shell with principal quantum number $n$ is given by $2n^{2}$.

Step2: Substitute $n = 2$

When $n = 2$, we calculate $2n^{2}=2\times2^{2}$.
$2\times2^{2}=2\times4 = 8$.

Answer:

8