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)