Chapter 11-13 Flashcards
alloy
A substance that has the characteristic properties of a metal and contains more than one element. Often there is one principal metallic component, with other elements present in smaller amounts. Alloys may be homogeneous or heterogeneous. (Section 12.3)
addition polymerization
Polymerization that occurs through coupling of monomers with one another, with no other products formed in the reaction. (Section 12.8)
amorphous solid
A solid whose molecular arrangement lacks the regularly repeating long-range pattern of a crystal. (Section 12.2)
band
An array of closely spaced molecular orbitals occupying a discrete range of energy. (Section 12.4)
Band gap
The energy gap between a fully occupied band called a valence band and an empty band called the conduction band. (Section 12.7)
band structure
The electronic structure of a solid, defining the allowed ranges of energy for electrons in a solid. (Section 12.7)
body-centered lattice
A crystal lattice in which the lattice points are located at the center and corners of each unit cell. (Section 12.2)
capillary action
The process by which a liquid rises in a tube because of a combination of adhesion to the walls of the tube and cohesion between liquid particles. (Section 11.3)
colligative property
A property of a solvent (vapor-pressure lowering, freezing-point lowering, boiling-point elevation, osmotic pressure) that depends on the total concentration of solute particles present. (Section 13.5)
colloids (colloidal dispersions)
Mixtures containing particles larger than normal solutes but small enough to remain suspended in the dispersing medium. (Section 13.6)
condensation polymerization
Polymerization in which molecules are joined together through condensation reactions. (Section 12.8)
condensation reaction
A chemical reaction in which a small molecule (such as a molecule of water) is split out from between two reacting molecules. (Sections 12.6 and 22.8)
conduction band
A band of molecular orbitals lying higher in energy than the occupied valence band and distinctly separated from it. (Section 12.7)
coordination number
The number of adjacent atoms to which an atom is directly bonded. In a complex the coordination number of the metal ion is the number of donor atoms to which it is bonded. (Sections 12.37 and 24.2)
copolymer
A complex polymer resulting from the polymerization of two or more chemically different monomers. (Section 12.8)
covalent-network solids
Solids in which the units that make up the three-dimensional network are joined by covalent bonds. (Section 12.1)
critical pressure
The pressure at which a gas at its critical temperature is converted to a liquid state. (Section 11.4)
critical temperature
The highest temperature at which it is possible to convert the gaseous form of a substance to a liquid. The critical temperature increases with an increase in the magnitude of intermolecular forces. (Section 11.4)
crystal lattice
An imaginary network of points on which the repeating motif of a solid may be imagined to be laid down so that the structure of the crystal is obtained. The motif may be a single atom or a group of atoms. Each lattice point represents an identical environment in the crystal. (Section 12.2)
crystalline solid (crystal)
A solid whose internal arrangement of atoms, molecules, or ions possesses a regularly repeating pattern in any direction through the solid. (Section 12.2)
crystallization
The process in which molecules, ions, or atoms come together to form a crystalline solid. (Section 13.2)
cubic close packing
A crystal structure where the atoms are packed together as close as possible, and the close-packed layers of atoms adopt a three-layer repeating pattern that leads to a face-centered cubic unit cell. (Section 12.3)
dipole–dipole force
A force that becomes significant when polar molecules come in close contact with one another. The force is attractive when the positive end of one polar molecule approaches the negative end of another. (Section 11.2)
dispersion forces
Intermolecular forces resulting from attractions between induced dipoles. Also called London dispersion forces. (Section 11.2)
doping
Incorporation of a hetero atom into a solid to change its electrical properties. For example, incorporation of P into Si. (Section 12.7)
dynamic equilibrium
A state of balance in which opposing processes occur at the same rate. (Section 11.5)
elastomer
A material that can undergo a substantial change in shape via stretching, bending, or compression and return to its original shape upon release of the distorting force. (Section 12.6)
electron-sea model
A model for the behavior of electrons in metals. (Section 12.4)
elemental semiconductor
A semiconducting material composed of just one element. (Section 12.7)
face-centered lattice
A crystal lattice in which the lattice points are located at the faces and corners of each unit cell. (Section 12.2)
heat of fusion
The enthalpy change, ΔH, for melting a solid. (Section 11.4)
heat of sublimation
The enthalpy change, ΔH, for vaporization of a solid. (Section 11.4)
heat of vaporization
The enthalpy change, ΔH, for vaporization of a liquid. (Section 11.4)
Henry’s law
A law stating that the concentration of a gas in a solution, Sg, is proportional to the pressure of gas over the solution: Sg
heterogeneous alloy
An alloy in which the components are not distributed uniformly; instead, two or more distinct phases with characteristic compositions are present. (Section 12.3)
hexagonal close packing
A crystal structure where the atoms are packed together as closely as possible. The close-packed layers adopt a two-layer repeating pattern, which leads to a primitive hexagonal unit cell. (Section 12.3)
hole
A vacancy in the valence band of a semiconductor, created by doping. (Section 12.7)
hydration
Solvation when the solvent is water. (Section 13.1)
hydrogen bonding
Bonding that results from intermolecular attractions between molecules containing hydrogen bonded to an electronegative element. The most important examples involve OH, NH, and HF. (Section 11.2)
hydrophilic
Water attracting. The term is often used to describe a type of colloid. (Section 13.6
hydrophobic
Water repelling. The term is often used to describe a type of colloid. (Section 13.6)
ideal solution
A solution that obeys Raoult’s law. (Section 13.5)
immiscible liquids
Liquids that do not dissolve in one another to a significant extent. (Section 13.3)
intermetallic compound
A homogeneous alloy with definite properties and a fixed composition. Intermetallic compounds are stoichiometric compounds that form between metallic elements. (Section 12.3)
intermolecular forces
The short-range attractive forces operating between the particles that make up the units of a liquid or solid substance. These same forces also cause gases to liquefy or solidify at low temperatures and high pressures. (Chapter 11: Introduction)
interstitial alloy
An alloy in which smaller atoms fit into spaces between larger atoms. The larger atoms are metallic elements and the smaller atoms are typically nonmetallic elements. (Section 12.3)
ion–dipole force
The force that exists between an ion and a neutral polar molecule that possesses a permanent dipole moment. (Section 11.2)
ionic solids
Solids that are composed of ions. (Section 12.1)
lattice points
Points in a crystal all of which have identical environments. (Section 12.2)
lattice vectors
The vectors a, b, and c that define a crystal lattice. The position of any lattice point in a crystal can be represented by summing integer multiples of the lattice vectors. (Section 12.2)
mass percentage
The number of grams of solute in each 100 g of solution. (Section 13.4)
metallic solids
Solids that are composed of metal atoms. (Section 12.1)
miscible liquids
Liquids that mix in all proportions. (Section 13.3)
molal boiling-point-elevation constant (Kb)
A constant characteristic of a particular solvent that gives the increase in boiling point as a function of solution molality: ΔTb
molal freezing-point-depression constant (Kf)
A constant characteristic of a particular solvent that gives the decrease in freezing point as a function of solution molality: ΔTf
molality
The concentration of a solution expressed as moles of solute per kilogram of solvent; abbreviated m. (Section 13.4)
molecular solids
Solids that are composed of molecules. (Sections 12.1 and 12.6)
monomers
Molecules with low molecular weights, which can be joined together (polymerized) to form a polymer. (Section 12.8)
nanomaterial
A solid whose dimensions range from 1 to 100 nm and whose properties differ from those of a bulk material with the same composition. (Section 12.1)
normal boiling point
The boiling point at 1 atm pressure. (Section 11.5)
normal melting point
The melting point at 1 atm pressure. (Section 11.6)
osmosis
The net movement of solvent through a semipermeable membrane toward the solution with greater solute concentration. (Section 13.5)
osmotic pressure
The pressure that must be applied to a solution to stop osmosis from pure solvent into the solution. (Section 13.5)
parts per billion (ppb)
The concentration of a solution in grams of solute per 10^9 (billion) grams of solution; equals micrograms of solute per liter of solution for aqueous solutions. (Section 13.4)
parts per million (ppm)
The concentration of a solution in grams of solute per 10^6 (million) grams of solution; equals milligrams of solute per liter of solution for aqueous solutions. (Section 13.4)
phase diagram
A graphic representation of the equilibria among the solid, liquid, and gaseous phases of a substance as a function of temperature and pressure. (Section 11.6)
plastic
A material that can be formed into particular shapes by application of heat and pressure. (Section 12.8)
polarizability
The ease with which the electron cloud of an atom or a molecule is distorted by an outside influence, thereby inducing a dipole moment. (Section 11.2)
polymer
A large molecule of high molecular mass, formed by the joining together, or polymerization, of a large number of molecules of low molecular mass. The individual molecules forming the polymer are called monomers. (Sections 12.1 and 12.8
primitive lattice
A crystal lattice in which the lattice points are located only at the corners of each unit cell. (Section 12.2)
saturated solution
A solution in which undissolved solute and dissolved solute are in equilibrium. (Section 13.2)
solubility
The amount of a substance that dissolves in a given quantity of solvent at a given temperature to form a saturated solution. (Sections 4.2 and 13.2)
solution alloy
A homogeneous alloy, where two or more elements are distributed randomly and uniformly throughout the solid. (Section 12.3)
solvation
The clustering of solvent molecules around a solute particle. (Section 13.1)
substitutional alloy
A homogeneous (solution) alloy in which atoms of different elements randomly occupy sites in the lattice. (Section 23.6)
supersaturated solution
A solution containing more solute than an equivalent saturated solution. (Section 13.2)
surface tension
The intermolecular, cohesive attraction that causes a liquid to minimize its surface area. (Section 11.3)
thermoplastic
A polymeric material that can be readily reshaped by application of heat and pressure. (Section 12.8)
thermosetting plastic
A plastic that, once formed in a particular mold, is not readily reshaped by application of heat and pressure. (Section 12.8)
triple point
The temperature at which solid, liquid, and gas phases coexist in equilibrium. (Section 11.6)
Tyndall effect
The scattering of a beam of visible light by the particles in a colloidal dispersion. (Section 13.6)
unit cell
The smallest portion of a crystal that reproduces the structure of the entire crystal when repeated in different directions in space. It is the repeating unit or building block of the crystal lattice. (Section 12.2)
unsaturated solution
A solution containing less solute than a saturated solution. (Section 13.2)
valence band
A band of closely spaced molecular orbitals that is essentially fully occupied by electrons. (Section 12.7)
vapor pressure
The pressure exerted by a vapor in equilibrium with its liquid or solid phase. (Section 11.5)
viscosity
A measure of the resistance of fluids to flow. (Section 11.3)
volatile
Tending to evaporate readily. (Section 11.5)
vulcanization
The process of cross-linking polymer chains in rubber. (Section 12.6)
entropy
randomness or disorder
