Ionic and Covalent Bonding, Lewis Structures, and VSEPR Theory

Vocabulary flashcards reviewing key definitions and concepts for ionic bonding, covalent bonding, Lewis structures, molecular geometry (VSEPR theory), and orbital hybridization.

Ion

A charged atom or group of atoms resulting from the gain or loss of electrons.

Cation

An atom or group of atoms with a positive charge due to the loss of electrons, typically formed by metals.

Anion

An atom or group of atoms with a negative charge due to the gain of electrons, typically formed by non-metals.

Valence Electrons

The electrons located in the outermost energy level of an atom.

Chemical Bond

An attractive force between atoms or ions that binds elements together as a unit.

Octet Rule

The principle stating that atoms gain, lose, or share electrons to achieve a stable outer shell of $8$ valence electrons, matching a noble gas configuration.

Ionic Bond

A chemical bond formed between a metal cation and a nonmetal anion through the transfer of electrons.

Ionic Compound

A compound composed of positive metal ions and negative nonmetal ions whose total combined charges equal zero.

Crystal Lattice Structure

A repeating three-dimensional pattern of arranged ions characteristic of solid ionic compounds.

Binary Ionic Compound

An ionic compound composed of exactly two different elements.

Ternary Ionic Compound

An ionic compound composed of more than two different types of elements, containing at least one polyatomic ion.

Polyatomic Ion

A charged group of covalently bonded atoms that acts as a single ionic unit.

Covalent Bond

A chemical bond formed between two or more nonmetals through the sharing of valence electrons.

Diatomic Molecule

A molecule consisting of two atoms of the same element bound together under ordinary conditions, specifically bromine, iodine, nitrogen, chlorine, hydrogen, oxygen, and fluorine (BrINClHOF).

Nonpolar Covalent Bond

A covalent bond in which electrons are shared equally between atoms with similar electronegativities, characterized by an electronegativity difference of less than $0.4$.

Polar Covalent Bond

A covalent bond in which electrons are shared unequally due to differences in electronegativity (difference between $0.4$ and $1.7$), creating partial positive and partial negative charges.

Electronegativity

The relative ability of an atom to attract shared electrons toward itself within a chemical bond.

Single Bond

A covalent bond formed by sharing one pair of valence electrons ($2$ electrons) between two atoms.

Double Bond

A covalent bond formed by sharing two pairs of valence electrons ($4$ electrons) between two atoms.

Triple Bond

A covalent bond formed by sharing three pairs of valence electrons ($6$ electrons) between two atoms.

Lewis Structure

A structural representation of chemical compounds where lines represent bonding electron pairs and pairs of dots represent nonbonding lone pairs of electrons.

Lone Pair

A pair of unshared valence electrons localized on a single atom and not involved in bonding.

Incomplete Octet

An exception to the octet rule where a stable atom or molecule has fewer than $8$ valence electrons, such as hydrogen requiring $2$ or boron requiring $6$.

Expanded Octet

An exception to the octet rule occurring in elements with d sublevels (Periods 3 to 7) where the central atom holds more than $8$ valence electrons, up to a maximum of $12$.

VSEPR Theory

Valence Shell Electron Pair Repulsion theory, which predicts three-dimensional molecular shape based on electron pairs around the central atom repelling each other to stay as far apart as possible.

Linear Geometry

A molecular shape with $2$ bonds attached to the central atom, $0$ lone pairs, and a bond angle of $180^\circ$.

Trigonal Planar Geometry

A molecular shape with $3$ bonds attached to the central atom, $0$ lone pairs, and a bond angle of $120^\circ$.

Tetrahedral Geometry

A molecular shape with $4$ bonds attached to the central atom, $0$ lone pairs, and a bond angle of $109.5^\circ$.

Trigonal Pyramidal Geometry

A molecular shape with $3$ bonds attached to the central atom, $1$ lone pair, and a bond angle of $107^\circ$.

Bent Geometry

A molecular shape with $2$ bonds attached to the central atom, $2$ lone pairs, and a bond angle of $105^\circ$.

Hybridization

The process of mixing atomic orbitals on the same atom as it forms bonds to generate new hybrid orbitals.

Hybrid Orbitals

Orbitals obtained by mixing two or more atomic orbitals on the same atom.