chemistry 9.1

Vocabulary flashcards covering the concepts of ionic, covalent, and metallic bonding, including the octet rule and basic chemical structures.

Octet Rule

The principle that atoms react chemically to achieve a noble-gas electron configuration, usually a filled outer shell, to produce highest stability.

Valence Electrons

The electrons in the outermost shell of an atom that participate in chemical bonding; for main group elements, the number of these electrons equals the group number.

Anions

Negative ions formed when a neutral atom receives or gains electrons.

Cations

Positive ions formed when a neutral atom loses electrons.

Ionic Bonds

Chemical bonds formed by the electrical attraction between positively charged and negatively charged ions, characterized by the transfer of electrons.

Empirical Formula

An expression providing the simplest ratio of ions in a crystalline compound, such as the $1:1$ ratio for $NaCl$.

Electronegativity

The capacity of an atom to attract electrons; significant differences in this property between atoms often result in ionic connections.

Covalent Bonds

Bonds formed when atoms share valence electrons, where the nuclei are held together by their mutual attraction to a shared negatively charged electron cloud.

Diatomic Molecule

A molecule formed when two atoms of the same element, such as hydrogen ($H_2$) or chlorine ($Cl_2$), share electrons.

Lone Pairs

Pairs of valence electrons that are not involved in a chemical bond; also referred to as nonbonding pairs.

Multiple Bond

A bond created when two atoms share two or three pairs of electrons, known specifically as double or triple bonds.

Structural Formula

A representation of a molecule where a single line symbolizes a single bond, two lines symbolize a double bond, and three lines symbolize a triple bond.

Covalent Networks

Large-scale structures such as diamond, quartz ($SiO_2$), or silicon carbide ($SiC$) where strong covalent bonds hold billions or trillions of atoms together in a single unit.

Metallic Bonds

The chemical bonds holding metal atoms together through a "sea" or "cloud" of delocalized electrons shared by all atoms in the vicinity.

Delocalized Electrons

Electrons in metallic bonding that move continually among all metal atoms rather than orbiting a single nucleus.

Malleable

A characteristic of metals that allows them to be hammered into various shapes because shifting the shape does not break metallic links.

Ductile

A characteristic of metals that allows them to be pulled into wires without crumbling or breaking.