Atomic orbital

Definition

An atomic orbital is a region in an atom where there is a high probability of finding electrons. Atomic orbitals are defined by quantum numbers and have specific shapes and orientations.

5 Must Know Facts For Your Next Test

1. Atomic orbitals are characterized by the principal quantum number (n), azimuthal quantum number (l), magnetic quantum number (m_l), and spin quantum number (m_s).
2. The shape of an atomic orbital is determined by the azimuthal quantum number (l): s-orbitals are spherical, p-orbitals are dumbbell-shaped, d-orbitals have more complex shapes.
3. Each type of orbital can hold a maximum of two electrons with opposite spins, according to the Pauli exclusion principle.
4. Orbitals within a subshell are degenerate, meaning they have the same energy level.
5. Electron configurations follow the Aufbau principle, Hund's rule, and Pauli exclusion principle to fill orbitals in increasing order of energy.

Review Questions

• What determines the shape of an atomic orbital?
• How many electrons can an atomic orbital hold?
• Explain what it means for orbitals within a subshell to be degenerate.

Related terms

Quantum Numbers:

Set of four numbers that describe the unique quantum state of an electron in an atom: principal (n), azimuthal (l), magnetic (m_l), and spin (m_s).

Pauli Exclusion Principle:

A rule stating that no two electrons in an atom can have identical sets of quantum numbers.

Aufbau Principle:

\text{A guideline for electron configuration that states electrons fill lower-energy orbitals first before moving to higher-energy ones.}