Chapter 11: Intermolecular Forces and Liquids and Solids Flashcards
Adhesion
Attraction between unlike molecules
Amorphous Solid
A solid that lacks a regular 3-D arrangement of atoms or molecules
Boiling Point
the temp at which the vapor pressure of a liquid is equal to the external atmospheric pressure
Closest Packing
the most efficient arrangements for packing atoms, molecules, or ions in a crystal
Cohesion
the intermolecular attraction between like molecules
Condensation
the phenomenon of going from the gaseous state to the liquid state
Coordination Number
In a crystal lattice it is defined as the number of atoms (or ions) surrounding an atom (or ion). In coordination compounds it is defined as the number of donor atoms surrounding the central metal atom in a complex.
Critical Pressure
the minimum pressure necessary to bring about liquefaction at the critical temperature.
Critical Temperature
the temperature at which a gas will not liquefy
Crystalline Solid
a solid that possesses rigid and long-range order; its atoms, molecules, or ions occupy specific positions
Deposition
the process in which the molecules go directly from the vapor into the solid phase
Dipole-dipole forces
forces that act between polar molecules
Dispersion forces
the attractive forces that arise as a result of temporary dipoles induced in the atoms or molecules; also called London forces
Dynamic equilibrium
the condition in which the rate of a forward process is exactly balanced by the rate of a reverse process
Equilibrium Vapor pressure
the vapor pressure measured under dynamic equilibrium of condensation and evaporation at some temperature
Evaporation
the process in which a liquid is transformed into a gas; also called vaporization
Freezing Point
the temperature at which the solid and liquid phases of a substance coexist at equilibrium
Glass
the optically transparent fusion product of inorganic materials that has cooled to a rigid state without crystallizing
Hydrogen Bond
A special type of dipole-dipole interaction between the hydrogen atom bonded to an atom of a very electronegative element (F,N,O) and another atom of one of the three electronegative elements
Induced dipole
The separation of positive and negative charges in a neutral atom (or a non polar molecule) caused by the proximity of an ion or a polar molecule
Intermolecular forces
Attractive forces that exist among molecules
Intramolecular forces
Forces that hold atoms together in a molecule
Ion-dipole forces
Forces that operate between an ion and a dipole
Melting Point
The temperature at which solid and liquid phases coexist in equilibrium
Molar heat of sublimation
The energy (in kilojoules) required to sublime one mole of a solid
Molar heat of vaporization
the energy (in kilojoules) required to vaporize one mole of a liquid
Phase
A homogenous part of a system in contact with other parts of the system but separated from them by a well-defined boundary.
Phase changes
transformation from one phase to another
Phase diagram
a diagram showing the conditions at which a substance exists as a solid, liquid, or vapor
Sublimation
The process in which molecules go directly from the solid into the vapor phase
Supercooling
cooling of a liquid below its freezing point without forming the solid
Surface Tension
the amount of energy required to stretch or increase the surface of a liquid by a unit area
Triple Point
the point at which the vapor, liquid, and solid states of a substance are in equilibrium
Unit Cell
The basic repeating unit of the arrangement of atoms, molecules, or ions in a crystalline solid
Van der Waals forces
the dipole-dipole, dipole-induced dipole, and dispersion forces
Vaporization
the escape of molecules from the surface of a liquid, also called evaporation
Viscosity
a measure of a fluids resistance to flow
X-ray diffraction
the scattering of X rays by the units of a regular crystalline solid
