Quantum Mechanics and Electron Configuration Vocabulary

Vocabulary flashcards covering quantum numbers, atomic orbitals, electron configurations, and principles governing electron arrangements from the lecture notes.

Ground state

The state of an atom in which it does not radiate any energy whatsoever.

Excited state

The state achieved when an atom gains energy, causing its electrons to jump to a higher orbit further from the nucleus.

Photon

A packet or particle of light energy released at a specific frequency when an excited electron falls back to a lower orbit.

Emission spectrum

The unique pattern of light frequencies emitted by an element, used by scientists to identify the composition of stars.

Heisenberg uncertainty principle

The principle stating that it is impossible to know precisely both the velocity and position of a particle at the same time.

Electron cloud

A region around the nucleus proposed by Schrodinger where electrons are located.

Atomic orbital

A three-dimensional region around the nucleus that describes the probable location of an electron.

Principal quantum number

Numbers assigned to main energy levels, ranging from $1$ through $7$, which correspond to the periods on the periodic table.

S orbital

A spherical atomic orbital existing as $1$ orbital per sublevel that can hold a maximum of $2$ electrons.

P orbital

A dumbbell-shaped atomic orbital existing as $3$ orbitals per sublevel that can hold a maximum of $6$ electrons total.

D orbital

A four-leaf clover-shaped atomic orbital existing as $5$ orbitals per sublevel that can hold a maximum of $10$ electrons total.

F orbital

An atomic orbital shaped like a cluster of grapes, existing as $7$ orbitals per sublevel that can hold a maximum of $14$ electrons total.

Electron configuration

A representation explaining the arrangement and locations of electrons within an atom's electron cloud.

Aufbau principle

The rule stating that electrons fill low-energy atomic orbitals first before occupying higher energy sublevels.

Pauli exclusion principle

The rule stating that a maximum of $2$ electrons can occupy a single orbital, provided they have opposite spins.

Hund's rule

The rule stating that single electrons with the same spin must occupy each equal-energy orbital before additional electrons with opposite spins occupy the same orbitals.

Orbital diagram

A visual representation of electrons in orbitals using arrows inside boxes.

Noble gas configuration notation

An abbreviated electron configuration method that uses bracketed symbols representing the noble gas from the previous period to replace core electron structures.

Valence electrons

The electrons in the s and p orbitals of the outermost energy level that determine an element's chemical properties.

Octet rule

The rule stating that $8$ electrons in the outer energy level are required for an atom to be chemically stable.