Question

What is the maximum number of electrons in an atom that can have n = 4 and magnetic quantum number = +1?

Answer 1

If n = 4, l = 0, 1, 2, 3
magnetic quantum number (m) can range between +l and -l
So, to have m = +1, we can have
$l=3\left(f\right),2\left(d\right),1\left(p\right)$ only. So, these three orbitals have m = +1
A given no. of 'm' represents an orbital and an orbital can contain two electrons.
Hence, for n = 4, m = +1
We can have $3\times 2=6$ electrons.