Covalent bond
a chemical bond in which atoms share a pair of valence electrons.
Diatomic molecule
a molecule that consists of two atoms.
Lewis diagram
a diagram that shows the element symbol surrounded by dots representing valence electrons and dashes that represent pairs of shared electrons.
Molecule
a group of two or more atoms joined by chemical bonds.
Noble gases
a group of chemical elements that do not readily form chemical bonds.
Nonmetal
an element that is generally a poor conductor of heat and electricity.
Octet rule
a rule of thumb that states that atoms are most stable when surrounded by eight valence electrons.
Shell
a particular region where electrons can orbit the nucleus of an atom.
Valence
the number of chemical bonds an element is capable of forming.
Valence electron
an electron in the outermost shell of an atom.