Question

what types of atomic orbitals are in the third principal energy level?
o p and d only
o s, p, d, and f
o s and p only
o s, p, and d only

Explanation:

The principal energy level \(n\) determines the types of orbitals. The possible values of the angular - momentum quantum number \(l\) are \(l = 0,1,\cdots,n - 1\). For the third principal energy level \(n=3\), \(l = 0\) (s - orbital), \(l = 1\) (p - orbital), and \(l = 2\) (d - orbital). The \(f\) - orbital (\(l = 3\)) is not present in the \(n = 3\) level because \(l\lt n\).

Answer:

\(s,p,\text{ and }d\text{ only}\)