Question

What quantum numbers defines a shell?

Answer 1

The angular momentum quantum number, "l"
l=n-1 to determine the value for each shape, where n is the principal quantum number, n (energy level).

Explanation:

The angular momentum quantum number, "l" (Letter L not a 1)
l=n-1 to determine the value for each shape, where n is the principal quantum number, n (energy level).
If n=1, then l=0. we obtain a sphere shaped orbital labeled s.
If n=2, then l=1, we obtain a dumb-bell shaped orbital labeled p.
If n=3, then l=2, we obtain a clover shaped orbital labeled d.
If n=4, then l=3, we obtain a doughnut (very complex)shaped orbital labeled f.