Honors Chemistry Unit 3: Quantum Model, Electron Configurations, VSEPR, and Periodic Trends

Vocabulary practice flashcards covering quantum atomic orbitals, rules for electron filling, molecular geometries (VSEPR theory), and periodic table trends.

s-orbital

A spherical atomic orbital consisting of 1 orbital per energy level, capable of holding up to 2 electrons.

p-orbital

A set of 3 dumbbell-shaped atomic orbitals ($2p_x$, $2p_y$, $2p_z$) oriented along the x, y, and z axes within a sublevel.

d-orbital

A set of 5 atomic orbitals ($d_{xz}$, $d_{yz}$, $d_{xy}$, $d_{x^2-y^2}$, $d_{z^2}$) present within the d sublevel.

f-orbital

A set of 7 complex atomic orbitals found within the f sublevel starting at energy level $n=4$.

Quantum Numbers

Values representing main energy levels ($n=1, 2, 3$, etc.) that describe the arrangement of electrons in an atom.

Electron Spin

The behavior of electrons as if they spin on their own axis in either a clockwise or counter-clockwise direction.

Pauli Exclusion Principle

A rule stating that an orbital can hold a maximum of two electrons, and these two electrons must spin in opposite directions.

Aufbau Principle

A principle stating that electrons are added one at a time to the lowest energy orbitals available until all the electrons of the atom are accounted for.

Hund's Rule

A rule stating that electrons occupy equal-energy orbitals singly so that a maximum number of unpaired electrons results before pairing up.

Electron Configuration

A notation that strings together the sublevel letters and superscript electron counts to represent an atom's electron layout.

Noble Gas Configuration

A shorthand electron configuration method where the symbol for the preceding noble gas is enclosed in brackets followed by the remaining electron arrangement.

VSEPR Theory

Valence Shell Electron Pair Repulsion theory; states that molecular shape adjusts so that valence-electron pairs stay as far apart as possible.

Linear Geometry

A molecular shape with 2 atoms bonded to the central atom and 0 lone pairs on the central atom, featuring a $180^\circ$ bond angle.

Bent Geometry

A molecular shape with 2 atoms bonded to the central atom and 1 or 2 lone pairs on the central atom.

Trigonal Planar

A flat molecular shape featuring 3 atoms bonded to the central atom and 0 lone pairs on the central atom, with bond angles of $120^\circ$.

Trigonal Pyramidal

A molecular shape featuring 3 atoms bonded to the central atom and 1 lone pair on the central atom, which pushes down on the other 3 atoms to create a pyramid shape.

Tetrahedral

A molecular shape featuring 4 atoms bonded to the central atom and 0 lone pairs on the central atom, with bond angles of $109.5^\circ$.

Octet Rule

The principle that atoms tend to gain, lose, or share electrons in order to acquire a full set of eight valence electrons.

Electronegativity

The relative ability of an atom to attract electrons in a chemical bond.

Ionization Energy

The energy required to remove an electron from a gaseous atom.

First Ionization Energy

The energy required to remove the first outer electron from a neutral gaseous atom.

Atomic Radius

Half the distance between adjacent nuclei in a crystal for metals, or half the distance between nuclei of identical chemically bonded atoms for nonmetals.

Ionic Radii

The size of an atom's ion; positive ions are smaller than their parent atoms, whereas negative ions are larger than their parent atoms.