Chesnut Chem 1212k Ch 13 Vocabulary

adhesive force
Force of attraction between a liquid and another surface.
allotropes
Different forms of the same element in the same physical state.
amorphous solid
A noncrystalline solid with no well-defined, ordered structure.
band
A series of very closely spaced, nearly continuous molecular orbitals that belong to the material as a whole.
band gap
An energy separation between an insulator’s highest filled electron energy band and the next higher-energy vacant band.
band theory of metals
A theory that accounts for the bonding and properties of metallic solids.
boiling point
The temperature at which the vapor pressure of a liquid is equal to the external pressure; also the condensation point.
capillary action
The drawing of a liquid up the inside of a small-bore tube when adhesive forces exceed cohesive forces, or the depression of the surface of the liquid when cohesive forces exceed adhesive forces.
Clausius-Clapeyron equation
An equation that relates the change in vapor pressure of a liquid to the change in its temperature and its molar heat of vaporization.
cohesive forces
All the forces of attraction among particles of a liquid.
condensation
The process by which a gas or vapor becomes a liquid; liquefaction.
condensed phases
The liquid and solid phases; phases in which particles interact strongly.
conduction band
A partially filled band or a band of vacant energy levels just higher in energy than a filled band; a band within which, or into which, electrons must be promoted to allow electrical conduction to occur in a solid.
coordination number
In describing crystals, the number of nearest neighbors of an atom or ion.
critical point
The combination of critical temperature and critical pressure of a substance.
critical pressure
The pressure required to liquefy a gas (vapor) at its critical temperature.
critical temperature
The temperature above which a gas cannot be liquefied; the temperature above which a substance cannot exhibit distinct gas and liquid phases.
crystal lattice
The pattern of arrangement of particles in a crystal.
crystalline solid
A solid characterized by a regular, ordered arrangement of particles.
deposition
The direct solidification of a vapor by cooling; the reverse of sublimation.
dipole-dipole interactions
Interactions between polar molecules, that is, between molecules with permanent dipoles.
dipole-induced dipole interaction
See Dispersion forces.
dispersion forces aka London forces
Very weak and very short-range attractive forces between short-lived temporary (induced) dipoles; also called London forces.
distillation
The separation of a liquid mixture into its components on the basis of differences in boiling points.
dynamic equilibrium
A situation in which two (or more) processes occur at the same rate so that no net change occurs.
enthalpy of fusion aka heat of fusion
The amount of heat required to melt a specific amount of a solid at its melting point with no change in temperature; usually expressed in J/g or kJ/mol; in the latter case it is called the molar heat of fusion.
enthalpy of solidification aka heat of solidification
The amount of heat that must be removed from a specific amount of a liquid at its freezing point to freeze it with no change in temperature; usually expressed in J/g or kJ/mol; in the latter case it is called the molar heat of solidification.
evaporation aka vaporization
The process by which molecules on the surface of a liquid break away and go into the gas phase.
freezing point aka the melting point
The temperature at which liquid and solid coexist in equilibrium; also the freezing point.
heat of condensation
The amount of heat that must be removed from a specific amount of a vapor at its condensation point to condense the vapor with no change in temperature; usually expressed in J/g or kJ/mol; in the latter case it is called the molar heat of condensation.
heat of fusion aka enthalpy of fusion
The amount of heat required to melt a specific amount of a solid at its melting point with no change in temperature; usually expressed in J/g or kJ/mol; in the latter case it is called the molar heat of fusion.
heat of solidification aka enthalpy of fusion
The amount of heat that must be removed from a specific amount of a liquid at its freezing point to freeze it with no change in temperature; usually expressed in J/g or kJ/mol; in the latter case it is called the molar heat of solidification.
heat of vaporization
The amount of heat required to vaporize a specific amount of a liquid at its boiling point with no change in temperature; usually expressed in J/g or kJ/mol; in the latter case it is called the molar heat of vaporization.
hydrogen bond
A fairly strong dipole-dipole interaction (but still considerably weaker than covalent or ionic bonds) between molecules containing hydrogen directly bonded to a small, highly electronegative atom, such as N, O, or F.
insulator
A poor conductor of electricity and heat.
intermolecular forces
Forces between individual particles (atoms, molecules, ions) of a substance.
intramolecular forces
Forces between atoms (or ions) within molecules (or formula units).
isomorphous
Refers to crystals having the same atomic arrangement.
LeChatelier’s Principle
A system at equilibrium, or striving to attain equilibrium, responds in such a way as to counteract any stress placed upon it.
London forces aka dispersion forces
ery weak and very short-range attractive forces between short-lived temporary (induced) dipoles; also called London forces.
melting point aka the freezing point
The temperature at which liquid and solid coexist in equilibrium; also the freezing point.
meniscus
The upper surface of a liquid in a cylindrical container.
metallic bonding
Bonding within metals due to the electrical attraction of positively charged metal ions for mobile electrons that belong to the crystal as a whole.
molar enthalpy of vaporization aka molar heat of vaporization
The amount of heat required to vaporize one mole of a liquid at its boiling point with no change in temperature; usually expressed in kJ/mol. See Heat of vaporization.
molar heat capacity
The amount of heat necessary to raise the temperature of one mole of a substance one degree Celsius with no change in state; usually expressed in kJ/mol · °C. See Specific heat.
molar heat of condensation
The amount of heat that must be removed from one mole of a vapor at its condensation point to condense the vapor with no change in temperature; usually expressed in kJ/mol. See Heat of condensation.
molar heat of fusion
The amount of heat required to melt one mole of a solid at its melting point with no change in temperature; usually expressed in kJ/mol. See Heat of fusion.
molar heat of vaporization aka molar enthalpy of vaporization
The amount of heat required to vaporize one mole of a liquid at its boiling point with no change in temperature; usually expressed in kJ/mol. See Heat of vaporization.
normal boiling point
The temperature at which the vapor pressure of a liquid is equal to one atmosphere pressure.
normal melting point
The melting (freezing) point at one atmosphere pressure.
phase diagram
A diagram that shows equilibrium temperature-pressure relationships for different phases of a substance.
polymorphous
Refers to substances that crystallize in more than one crystalline arrangement.
semiconductor
A substance that does not conduct electricity well at low temperatures but that does at higher temperatures.
specific heat
The amount of heat necessary to raise the temperature of a specific amount of a substance one degree Celsius with no change in state; usually expressed in J/g · °C. See Molar heat capacity.
sublimation
The direct vaporization of a solid by heating without passing through the liquid state.
supercritical fluid
A substance at a temperature above its critical temperature. A supercritical fluid cannot be described as either a liquid or gas, but has the properties of both.
surface tension
The result of inward intermolecular forces of attraction among liquid particles that must be overcome to expand the surface area.
triple point
The point on a phase diagram that corresponds to the only pressure and temperature at which three phases (usually solid, liquid, and gas) of a substance can coexist at equilibrium.
unit cell
The smallest repeating unit showing all the structural characteristics of a crystal.
vapor pressure
The partial pressure of a vapor in equilibrium with its parent liquid or solid.
vaporization aka evaporation
The process by which molecules on the surface of a liquid break away and go into the gas phase.
viscosity
The tendency of a liquid to resist flow; the inverse of its fluidity.
volatility
The ease with which a liquid vaporizes.