chemical bond
a mutual electrical attraction between the nuclei and valence electrons of different atoms that binds the atoms together
ionic bonding
chemical bonding that results from the electrical attraction between large numbers of cations and anions
covalent bonding
results from the sharing of electron pairs between two atoms
nonpolar-covalent bond
a covalent bond in which the bonding electrons are shared equally by the bonded atoms, resulting in a balanced distribution of electrical charge
polar
bonds that have an uneven distribution of charge
polar-covalent bond
a covalent bond in which the bonded atoms have an unequal attraction for the shared electrons
molecule
a neutral group of atoms that are held together by covalent bonds
molecular compound
a chemical compound whose simplest units are molecules
chemical formula
the relative numbers of atoms of each kind in a chemical compound by using atomic symbols and numerical subscripts
molecular formula
shows the types and numbers of atoms combined in a single molecule of a molecular compound
diatomic molecule
a molecule containing only two atoms
bond length
the average distance between two bonded atoms
bond energy
the energy required to break a chemical bond and form neutral isolated atoms
octet rule
chemical compounds tend to form so that each atom, by gaining, losing, or sharing electrons, has an octet of electrons in its highest occupied energy level
electron-dot notation
an electron-configuration notation in which only the valence electrons of an atom of a particular element are shown, indicated by dots placed around the element's symbol
unshared pair (lone pair)
a pair of electrons that is not involved in bonding and that belongs exclusively to one atom
lewis structures
formulas in which atomic symbols represent nuclei and inner-shell electrons, dot-pairs or dashes between two atomic symbols represent electron pairs in covalent bods, and dots adjacent to only one atomic symbol represent unshared electrons
structural formula
indicates the kind, number, arrangement, and bonds but not the unshared pairs of the atoms in a molecule
single bond
a covalent bond produced by the sharing of one pair of electrons between two atoms
double bond
a covalent bond produced by the sharing of two pairs of electrons between two atoms
triple bond
a covalent bond produced by the sharing of three pairs of electrons between two atoms
multiple bonds
double and triple bonds
resonance
bonding in molecules or ions that cannot be correctly represented by a single Lewis structure
ionic compound
composed of positive and negative ions that are combined so that the numbers of positive and negative charges are equal
formula unit
the simplest collection of atoms from which an ionic compound's formula can be established
lattice energy
the energy released when one mole of an ionic crystalline compound is formed from gaseous ions
polyatomic ion
a charged group of covalently bonded atoms
metallic bonding
the chemical bonding that results from the attraction between metal atoms and the surrounding sea of electrons
malleability
the ability of a substance to be hammered or beaten into thin sheets
ductility
the ability of a substance to be drawn, pulled, or extruded through a small opening to produce a wire.
molecular polarity
the uneven distribution of molecular charge
VSEPR theory
the repulsion between the sets of valence-level electrons surrounding an atom causes these sets to be oriented as far apart as possible
hybridization
the mixing of two or more atomic orbitals of similar energies on the same atom to produce new orbitals of equal energies
hybrid orbitals
orbitals of equal energy produced by the combination of two or more orbitals on the same atom
intermolecular forces
the forces of attraction between molecules
dipole
created by equal but opposite charges that are separated by a short distance
dipole-dipole forces
the forces of attraction between polar molecules
hydrogen bonding
the intermolecular force in which a hydrogen atom that is bonded to a highly electronegative atom is attracted to an unshared pair of electrons of an electronegative atom in a nearby molecule
london dispersion forces
the intermolecular attractions resulting from the constant motion of electrons and the creation of instantaneous dipoles