Secondary (angular momentum) quantum number

Definition

The secondary (angular momentum) quantum number, denoted as $l$, determines the shape of an electron's orbital. It can take any integer value from 0 to $n-1$ where $n$ is the principal quantum number.

5 Must Know Facts For Your Next Test

1. The secondary quantum number $l$ defines the subshells within a principal energy level.
2. $l = 0$ corresponds to an s orbital, $l = 1$ to a p orbital, $l = 2$ to a d orbital, and $l = 3$ to an f orbital.
3. The value of $l$ affects the orbital angular momentum of an electron, which is given by $\sqrt{l(l+1)}\hbar$.
4. Each value of $l$ has specific magnetic quantum numbers ($m_l$), ranging from -$l$ to +$l$, including zero.
5. In multi-electron atoms, different values of $l$ lead to different energy levels due to electron-electron interactions.

Review Questions

Related terms

Principal Quantum Number:

The principal quantum number, denoted as $n$, indicates the main energy level occupied by an electron.

Magnetic Quantum Number:

The magnetic quantum number, denoted as $m_l$, specifies the orientation of an orbital around the nucleus within a subshell.

Spin Quantum Number:

The spin quantum number, denoted as $m_s$, describes the intrinsic spin of an electron within an orbital and can be either +1/2 or -1/2.