Quantum Mechanics and Atomic Models Flashcards

Grade 12 · Science · Flashcards

Master key quantum mechanics vocabulary and concepts for Grade 12 Science.

Flashcards

Quantum mechanical model: The modern atomic model describing electrons as probability clouds (orbitals) rather than fixed orbits.
Wave function (ψ): A mathematical function describing the quantum state of an electron; ψ² gives probability of finding the electron at a location.
Orbital: A region in space where there is a high probability (usually 90%) of finding an electron.
Principal quantum number (n): Defines the energy level; higher n = higher energy and larger orbital size.
Subshell: A subdivision of an energy level defined by the angular momentum quantum number l (s, p, d, f).
Pauli Exclusion Principle: No two electrons in an atom can have identical sets of four quantum numbers.
Hund's Rule: Electrons fill orbitals of equal energy one at a time before pairing; single electrons have parallel spins.
Aufbau Principle: Electrons fill available orbitals starting at the lowest energy level first.
Heisenberg Uncertainty Principle: The more precisely the position of a particle is known, the less precisely its momentum can be known, and vice versa.
Photoelectric effect: The emission of electrons from a material when light shines on it; explained by Einstein as evidence of light's particle nature (photons).
de Broglie wavelength: λ = h/mv; all matter has an associated wavelength inversely proportional to its momentum.
Ground state: The lowest energy configuration of an atom's electrons; the most stable arrangement.