Question

Which of the following properties of orbitals are described by magnetic quantum number?

• A. Spin
• B. Orientation
• C. Size
• D. Shape

Answer 1

The correct option is B Orientation

Magnetic quantum number is one of the quantum numbers represented by ${\text{m}}_{\text{l}}$.
The values of this number describes the orientation of the orbital in space relative to the other orbitals in the atom.
For a certain value of l there are (2l + 1) integer values of ${\text{m}}_{\text{l}}$.
When $\text{l}=0$, $\text{2l +1}$ = 1 and there is only one value of ${\text{m}}_{\text{l}}$, thus we have only one orbital i.e., s.
When $\text{l}=1$, $\text{2l +1}$ = 3, that means ${\text{m}}_{\text{l}}$ has three values, -1, 0 and +1. Thus, p orbitals have three different orientations along x, y, z axes. These are labelled as ${\text{p}}_{\text{x}},{\text{p}}_{\text{y}},\text{and}{\text{p}}_{\text{z}}$.