Chapter_5_Heating_and_Changes_of_State_A_Story_of_Polarity_and_Intermolecular_Forces_released

VSEPR theory

Valence-shell electron-pair repulsion theory; used to predict molecular shapes based on the repulsion between electron pairs.

Electronegativity

A measure of the tendency of an atom to attract electrons.

Polarity

The distribution of electrical charge between atoms bonded together.

Nonpolar covalent bond

A covalent bond in which the bonding pair of electrons is shared equally by the bonded atoms.

Polar covalent bond

A covalent bond that shows bond polarization; the bonding electrons are shared unequally.

Exothermic process

A process that liberates heat.

Endothermic process

A process that absorbs heat.

Kinetic energy

The energy a particle has as a result of its motion.

Potential energy

The energy that is stored in particles due to their position, composition, or arrangement.

Intermolecular forces

The attractive forces that exist between molecules.

Ion-dipole interaction

The attraction between a charged ion and a polar molecule.

Hydrogen bonding

The attraction between a hydrogen atom bonded to F, N, or O and any F, N, or O atom on another molecule.

Dipole-dipole interaction

The attractive force between the positive end of one polar molecule and the negative end of another.

London dispersion forces

Very weak attractive forces acting between particles of all matter, resulting from momentary nonsymmetric electron distributions.

Boiling point

The temperature at which the vapor pressure of a liquid is equal to the prevailing atmospheric pressure.

Heat of fusion

The amount of heat energy required to melt exactly 1 g of a solid substance at constant temperature.

Heat of vaporization

The amount of heat energy required to vaporize exactly 1 g of a liquid substance at constant temperature.

Specific heat

The amount of heat energy required to raise the temperature of exactly 1 g of a substance by exactly 1°C.

Condensation

An exothermic process in which a gas or vapor is changed to a liquid.

Sublimation

The endothermic process in which a solid is changed directly to a gas without first becoming a liquid.

Deposition

The exothermic process in which a gas is changed directly to a solid without first becoming a liquid.

Compressibility

The change in volume of a sample resulting from a pressure change acting on the sample.

Physical properties of solids

High density, definite shape, low compressibility, strong particle interactions, little molecule movement.

Physical properties of liquids

High density, indefinite shape, low compressibility, intermediate particle interactions, substantial molecule movement.

Physical properties of gases

Low density, indefinite shape, high compressibility, weak particle interactions, extreme molecule movement.