Electron Configurations and Atomic Models

Flashcards covering key concepts of electron configurations and the evolution of atomic models.

Electron Configuration

The ways in which electrons are arranged in various orbitals around the nucleus.

Dalton Model

Pictured atoms as tiny and indestructible solid spheres with no internal structure.

Thomson Model

Portrayed atoms as spheres of positive charge with embedded negatively charged electrons, also known as the Plum Pudding model.

Rutherford Model

Proposed a tiny, dense, positively charged nucleus with electrons moving around it in mostly empty space.

Bohr Model

Suggested that electrons move in circular orbits at fixed distances from the nucleus, with fixed energy levels.

Quantum Mechanical Model

Uses mathematical equations to describe electron behavior, stating that electron location is a fuzzy cloud rather than a defined path.

Principle Quantum Number (n)

Indicates the main energy level surrounding a nucleus.

Orbital Quantum Number

Also known as sublevels or subshells, indicates the shape of an orbital.

Spin Quantum Number

Indicates the direction of electron spin, with only two possible values.

Aufbau Principle

States that electrons occupy the lowest energy orbital available to them.

Hund's Rule

States that orbitals of equal energy are each occupied by one electron before any one orbital is occupied by a second electron.

Pauli Exclusion Principle

States that an atomic orbital may describe at most two electrons with opposite spins.

Ground State

The lowest energy state of an electron in an atom.

Excited State

Higher energy state of an electron after absorbing energy.

Valence Electrons

Electrons located in the outermost energy level of an atom.

Electron-Dot Notation

Shows only the valence electrons in the highest energy level of an atom.