electronic configuration

Bohr Spectra

Different colored lines produced by elements when white light is passed through a prism, indicating unique line spectra for each element.

Energy Level

A fixed energy value that an electron in an atom may have.

Ground State

The state of an atom where the electron occupies the lowest available energy level.

Excited State

A state where the electron occupies higher energy levels than that of the ground state, and it is unstable.

Quantum Energy Absorption

The process in which an atom absorbs energy causing electrons to jump to higher energy levels.

Photon

A particle of light emitted when an electron returns to its ground state.

Paschen Series

A series found in the infrared region, corresponding to transitions from n=5 to n=3.

Balmer Series

Visible series associated with electron transitions that can be seen; includes transitions from n=5 to n=2 and n=3 to n=2.

Heisenberg's Uncertainty Principle

States that it is impossible to measure both the velocity and position of an electron at the same time.

Atomic Orbital

A region of space around the nucleus of an atom where there is a high possibility of finding an electron.

Energy Sublevel

A group of atomic orbitals within an atom that have the same energy.

Aufbau Principle

Principle stating that electrons fill the lowest vacant energy levels first when building an electron configuration.

Pauli Exclusion Principle

No more than 2 electrons can occupy an orbital, and they must have opposite spins.

Hund’s Rule

Electrons occupy vacant sublevels singly before pairing up in orbitals of equal energy.

Electronic Configuration

The arrangement of electrons in the atoms of an element, represented by energy levels, sublevels, and number of electrons.

1s, 2s, 2p, 3s, 3p, 4s

Designations of electron sublevels representing the distribution of electrons in an atom.

D-block elements stability rule

D-block elements with half-filled or completely filled sublevels exhibit extra stability.

Example of Chromium Configuration

Chromium has an actual electron configuration of 1s2 2s2 2p6 3s2 3p6 4s1 3d5, deviating from expected configuration due to extra stability.