Atomic Structures: Electron Configuration

Chem 10 H

Spectra

The different wavelengths of light passing through a prism at different angles, resulting in a continuous spectrum blending all colors together.

Emission line spectrum

A discontinuous spectrum produced when an atom, element, or molecule in an excited state returns to a lower energy state, emitting energy in quantized amounts.

Quantum Mechanics

The study of the motion of atomic or subatomic objects that exhibit wave-particle duality, where the motion is affected by gaining or losing energy in discrete amounts called quanta.

Electron cloud

The location of electrons in the quantum mechanical model of the atom, characterized by variable densities indicating the probability of finding an electron.

Heisenberg Uncertainty Principle

The principle stating that it is impossible to simultaneously determine the position and velocity of a particle, leading to an uncertain volume of space where an electron may exist.

Quantum Mechanical Atomic Model

A model that treats electrons mathematically as waves and describes energy in terms of the probability of locating the electron in a region of space outside the nucleus.

Quantum Numbers

Four quantum numbers used to describe the energy level, shape, orientation, and spin of an electron in an atom.

Principal quantum number

Describes the most probable distance of electrons from the nucleus and has whole number values representing principal energy levels.

Sublevel

The second quantum number that determines the shape of atomic orbitals, with values corresponding to s, p, d, and f orbitals.

Orbital

The third quantum number that specifies the orientation in space of an orbital, with values indicating the number of orbitals in each sublevel.

Electron spin

The fourth quantum number that describes the spin of an electron on its axis, with values representing opposite spins.

Electron Configuration

The arrangement of electrons in an atom's orbitals, following the Aufbau principle and Hund's rule.

Transition Elements

Elements that complete inner energy levels before completing outer energy levels, characterized by the filling of 3d orbitals after 4s orbitals.

Aufbau Principle

The principle stating that electrons occupy orbitals in order of increasing energy, from lowest to highest.

Noble Gases

Elements with full outermost principal energy levels, making them chemically inert and not readily forming chemical bonds with other elements.

Abbreviated Notation Using Noble Gases

A shortcut for writing electron configurations by using the closest noble gas as a reference and omitting the matching notation.