Question

which characteristic is given by the angular momentum quantum number?
orbital size
orbital mass
orbital shape
orbital orientation

Explanation:

In quantum mechanics, the angular - momentum quantum number ($l$) determines the shape of the atomic orbital. The principal quantum number ($n$) is related to orbital size, the magnetic quantum number ($m_l$) is related to orbital orientation, and there is no quantum number directly related to orbital mass.

Answer:

orbital shape