absolute zero

the temperature at which all molecular motion should cease(two words)

accelerator

a device that is used to accelerate charged particles to high speeds

accuracy

the relationship between the graduations on a measuring device and the actual standard for the quantity being measured

acid

a substance that produces hydrogen ions in water solution; a proton donor

acidic anhydride

a nonmetallic oxide that can react with water to form an acid(two words)

actinoid series

fourteen elements beginning with actinium in which the arrow diagram predicts the highest energy electrons to be in the 5f sublevel(two words)

activated complex

an assembly of atoms in an excited state between reactants and products in a chemical reaction(two words)

activation energy

the [energy] required to form the activated complex(two words)

activity

the effective concentration of a species

addition polymerization

the formation of a polymer through addition reactions(two words)

addition reaction

a [reaction]; the combining of two or more molecules through adding on at the double or triple bond of an unsaturated organic compound(two words)

adiabatic system

[system] in which heat neither leaves nor enters(two words)

adsorption

the process of one substance being attracted and held to the surface of another substance

alcohol

one of a class of organic compounds characterized by the presence of the hydroxyl group, -OH

aldehyde

one of the class of organic compounds characterized by the presence of the carbonyl group (>C = 0) on the end of the carbon chain(RCHO)

aliphatic

hydrocarbons consisting of chains or nonaromatic rings

alkali metal

an element in Group 1(IA)(two words)

alkaline earth metal

an element in Group 2(IIA)(three words)

alkane

an aliphatic hydrocarbon having only single carbon-carbon bonds

alkene

an aliphatic hydrocarbon having one or more double bonds

alkyne

an aliphatic hydrocarbon having one or more triple bonds

allotrope

form of an element differing in crystal or molecular structure

alloy

a mixture of a metal and one or more other elements, usually metals

alpha particle

a helium nucleus(two words)

amide

an organic compound containing the -CO-NH2 group; an inorganic compound containing NH2

amine

an organic compound derived from ammonia by replacement of one or more hydrogen atoms by hydrocarbon radicals

amino acid

an organic compound characterized by the presence of an amino group and a carboxyl group on the same carbon atom(two words)

amorphous

a non-crystalline material that appears solid but without long-range order; supercooled liquid

ampere

the unit of electric current equal to one coulomb per second

amphoteric

having the ability to act as either an acid or a base

amplitude

the maximum value attained by a wave

anhydrous

without water

anion

a negative ion

anode

the positive electrode (general); the electrode at which oxidation occurs (electrochemical)

antiparticle

a particle identical to a second particle in all respects except for opposite charge and magnetic moment

aromatic compound

an organic ring [compound] containing one or more benzene rings(two words)

arrow diagram

a system for predicting the order of filling energy sublevels with electrons(two words)

atom

the smallest particle of an element

atomic mass

the [mass] of an atom in atomic mass units; the average mass of the atoms of an element(two words)

atomic mass unit

one-twelfth the mass of the carbon-12 atom(three words)

atomic number

the [number] of protons in the nucleus of an atom(two words)

atomic radius

the distance from the center of an atom to the 90% probability surface of the electron cloud(two words)

atomic theory

the body of knowledge concerning the existence of atoms and their characteristic structure(two words)

Avogadro constant

the number of objects in a mole; 6.022 136 7 x 10^23(two words)

Avogadro's principle

The [principle] that equal volumes of gases at the same temperature and pressure contain the same number of molecules.(two words, possessive)

balance

an instrument used to measure mass

barometer

a manometer used to measure atmospheric pressure

baryon

a subatomic particle classified as a heavy hadron

base

a substance that produces hydroxide ions in water solution; a proton acceptor

basic anhydride

a metallic oxide that will react with water to form a base(two words)

beta particle

an electron (-) or positron (+)(two words)

binary acid

an [acid] containing only hydrogen and one other element(two words)

binary compound

a [compound] composed of only two elements(two words)

binding energy

the [energy] required to split the nucleus into separate nucleons(two words)

biochemistry

the study of the substances and reactions involved in life processes

body-centered cubic

having a unit cell with a particle at each vertex of a cube and a particle in the center of the cube(three words, hyphenated)

Bohr atom

planetary [atom] model(two words)

boiling point

the temperature at which the vapor pressure of a liquid equals the atmospheric pressure(two words)

bond

the force holding atoms together in a compound or molecule

bond angle

the [angle] between two bond axes extending from the same atom(two words)

bond axis

the imaginary line connecting the nuclei of two bonded atoms(two words)

bond character

the relative ionic or covalent nature of a chemical bond(two words)

bond length

the distance between the nuclei of bonded atoms (two words)

bond strength

the energy required to break a bond(two words)

Boyle's law

The volume of a specific amount of gas varies inversely as the pressure if the temperature remains constant.(two words, possessive)

branch

a carbon group, named as a radical, that is attached to the main carbon chain in an organic compound

Brownian motion

the random [motion] of colloidal particles due to their bombardment by the molecules of the dispersing medium(two words)

buffer system

a solution that can receive moderate amounts of either acid or base without significant change in its pH.(two words)

calorimeter

a device for measuring the transfer of heat during a chemical or physical change

capillary rise

the tendency of a liquid to [rise] in a tube of small diameter due to the surface tension of the liquid(two words)

carbide ion

a carbon atom that has gained four electrons; C^4-(two words)

carbohydrate

compounds of carbon, hydrogen, and oxygen that are mostly simple sugars or condensation polymers of sugars

carboxylic acid

the class of organic compounds characterized by the carboxyl group (-COOH)(two words)

catalysis

the speeding up of chemical reactions by the presence of a substance that is unchanged after the reaction

catalyst

a substance that speeds a chemical reaction without being permanently changed itself

catenation

the joining of like atoms in chains.

cathode

the negative electrode (general); the electrode at which reduction occurs (electrochemical)

cathode rays

the beam of electrons in a gas discharge tube(two words, plural)

cation

a positive ion

cell potential

the voltage obtained from a voltaic cell(two words)

cellulose

a woody polymer of glucose

Celsius scale

the temperature scale based on the boiling point of water as 100 degrees and the freezing point of water as 0 degrees(two words)

chain reaction

a [reaction] in which the product from each step acts as a reactant for the next step(two words)

chalcogen

an element in Group 16(VIA)

Charles's law

The volume of a specific amount of gas varies directly as the absolute temperature if the pressure remains constant.(two words, possessive)

chemical change

a [change]; a rearrangement of atoms and/or molecules to produce one or more new substances with new properties(two words)

chemical formula

the notation using symbols and numerals to represent the composition of substances(two words)

chemical property

a [property] characteristic of a substance when it is involved in a chemical change(two words)

chemical reaction

a [reaction] in which one or more substances are changed into one or more new substances(two words)

chemical symbol

a notation using one to three letters to represent an element(two words)

chemistry

the study of the structure and properties of matter

chromatography

the separation of a mixture using a technique based upon differential adsorption between a stationary phase and a mobile phase

closest packing

the crystal structure in which space between particles is minimized(two words)

coefficient

a numeral, representing the number of formula units of the substance, placed before a formula

colligative properties

the [properties] of solutions that depend only on the number of particles present without regard to type(two words, plural)

colloid

a dispersion of particles from 1 nm to 100 nm in at least one dimension in a continuous medium

colloid chemistry

the study of colloids, especially of surfaces(two words)

column chromatography

[chromatography] in which the stationary phase is held in a column(two words)

combustion

burning, or reaction with oxygen producing heat and usually light

common ion effect

an equilibrium phenomenon in which an ion common to two or more substances in a solution shifts the point of equilibrium away from itself(three words)

complex ion

a central positive [ion] surrounded by bonded ligands(two words)

compound

a substance composed of atoms of two or more elements linked by chemical bonds

concentrated solution

a solution with a high ratio of solute to solvent(two words)

concentration

the ratio of the amount of solute to the amount of solvent or solution

condensation polymerization

the formation of a polymer and a small molecule, usually water, from monomers(two words)

condensed state

solid or liquid(two words)

conductivity

the relative ability to conduct heat and electricity

conjugate acid

the particle obtained after a base has gained a proton(two words)

conjugate base

the particle remaining after an acid has donated a proton(two words)

conjugated system

a group of four or more adjacent atoms in a molecule with an extended pi-bonding system(two words)

consumer product

an item for sale to the general public(two words)

contact catalyst

a [catalyst] that functions by adsorbing one of the reactants on its surface; a heterogeneous catalyst(two words)

containment vessel

a reinforced concrete and steel structure designed to contain any leakage from a nuclear reactor(two words)

continuous phase

the dispersing medium in a colloid(two words)

control rod

the neutron-absorbing substance used to control the rate of reaction in a nuclear reactor(two words)

coordinate covalent bond

a covalent [bond] in which both electrons of the shared pair come from the same atom(three words)

coordination number

the [number] of points at which ligands are attached to the central atom or ion in a complex ion or coordination compound(two words)

corrosion

the chemical interaction of a metal with its environment

coulomb

the quantity of electrical charge equal to the flow of one ampere for one second

counting number

natural [number]; any cardinal number except zero(two words)

covalent bond

a [bond] characterized by the sharing of one or more pairs of electrons between two atoms(two words)

covalent radius

the [radius] of an atom along the bond axis(two words)

critical pressure

the [pressure] needed to liquefy a gas at its critical temperature(two words)

critical temperature

the highest [temperature] at which the vapor and liquid states of a substance can exist in equilibrium(two words)

crystal

a solid in which the particles are arranged in a regular, repeating pattern; a lattice

crystal defect

an imperfection in a crystal lattice(two words)

crystallization

the forming of crystals by evaporation or cooling

crystalloid

a substance that can penetrate a semipermeable membrane

cubic closest packing

face-centered cubic(three words)

cyclic

consisting of atoms bonded in a closed ring

cycloalkanes

hydrocarbons in which the carbon atoms are bonded in a ring and all bonds are single bonds(plural)

Dalton's law

In a mixture of gases, the total pressure of the mixture is the sum of the partial pressures of each component gas.(two words, possessive)

de Broglie's hypothesis

the [hypothesis] that particles may have the properties of waves.(two words, possessive)

decomposition

a reaction in which a compound breaks into two or more simpler substances

degenerate

having the same energy

dehydrating agent

a substance that can absorb water from other substances(two words)

deliquescent

the property of a solid to absorb sufficient water from the air to form a liquid solution

delocalization

the concept in which bonding electrons are not confined to the region between two atoms, but may be spread over several atoms or a whole piece of metal

density

mass per unit volume

desiccant

a drying agent

didentate

a ligand that attaches to the central ion in a complex in two places

diffusion

the spontaneous spreading of particles throughout a given volume until they are uniformly distributed

dilute solution

a [solution] with a low ratio of solute to solvent(two words)

dipeptide

two amino acids joined by an amide link

dipole

a polar molecule

dipole-dipole force

an attraction between dipoles; component of van der Waals forces(three words, hyphenated)

dipole-induced dipole force

an attraction between a dipole and a nonpolar molecule that has been induced to become a dipole; component of van der Waals forces(four words, hyphenated)

dipole moment

the strength of a dipole expressed as charge multiplied by distance(two words)

dislocation

a crystal defect

dispersed phase

colloidal particles distributed throughout the continuous phase(two words)

dispersion forces

the [forces] between particles that are not permanent dipoles; component of van der Waals forces(two words, plural)

dissociation

the separation of ions in solution

distillation

a separation method based on the evaporation of a liquid and the condensation of its vapor

doping

the addition of impurities to a semiconductor to increase electrical conductivity

double bond

a covalent [bond] in which two atoms share two pairs of electrons(two words)

double displacement

a chemical reaction in which the positive part of one compound combines with the negative part of another compound, and vice versa(two words)

drift tube

an uncharged [tube] through which particles being accelerated travel while the decelerating part of an electromagnetic wave passes(two words)

ductility

noun--the ability of a substance to be drawn out into a thin wire

dynamic equilibrium

the state in which two opposite changes take place simultaneously and at the same rate so that there is no overall change in the system(two words)

edge dislocation

crystal defect in which an extra layer of atoms is found between unit cells(two words)

effusion

the movement of gas through a small opening

elastic

describing collisions in which kinetic energy is conserved

elastomer

a substance that can be deformed under the influence of an outside force but will return to its original shape once the force is removed

electric current

the flow of charged particles(two words)

electrochemistry

the study of the interaction of electric current and chemical reactions

electrode potential

the [potential] of a reduction half-cell compared to that of the standard hydrogen half-cell(two words)

electrolysis

a chemical change caused by an electric current

electrolyte

a substance whose aqueous solution conducts electricity

electrolytic cell

an electric [cell] in which passage of an electric current causes a chemical reaction(two words)

electrolytic conduction

the migration of ions in solution(two words)

electromagnetic energy

radiant [energy]; energy transferred by electromagnetic waves(two words)

electron

an elementary particle with unit negative charge

electron affinity

the attraction of an atom for an electron(two words)

electron cloud

the space effectively occupied by an electron in an atom(two words)

electron configuration

a description of the arrangement of the electrons in an atom(two words)

electronegativity

the relative attraction of an atom for a shared pair of electrons

electronic conduction

the flow of electrons in a metal(two words)

electrophoresis

the migration of colloidal particles in an electric field

element

a substance whose atoms all have the same number of protons in the nucleus

elimination reaction

an organic [reaction] in which a small molecule is removed from a larger molecule leaving a double bond in the larger molecule(two words)

empirical formula

the [formula] giving the simplest ratio between the atoms of the elements present in a compound(two words)

endergonic

a process having an increase in Gibbs free energy

endothermic

a change that takes place with the absorption of heat

endpoint

the point in a titration where equivalent amounts of reactants are present

energy

a property of matter that can be converted to work under the proper circumstances

energy level

a specific energy or group of energies that may be possessed by electrons in an atom(two words)

energy sublevel

a specific energy that may be possessed by electrons within an energy level in an atom(two words)

enthalpy

that part of the energy of a substance that is due to the motion of its particles added to the product of its volume and pressure

enthalpy of formation

the net amount of energy produced or consumed when a mole of a compound is formed from its elements(three words)

enthalpy of fusion

the energy required to change 1 gram of a substance from solid to liquid(three words)

enthalpy of reaction

the change in enthalpy accompanying a chemical [reaction](three words)

enthalpy of solution

the change in enthalpy when one substance is dissolved in another(three words)

enthalpy of vaporization

the energy needed to change 1 gram of a substance from liquid to gas(three words)

entropy

the degree of disorder in a system

enzyme

a biological catalyst

equation

a symbolic expression representing a chemical change

equilibrium

a state in which no net change takes place in a system

equilibrium constant

a mathematical expression giving the ratio of the product of the concentrations of the products to the product of the concentrations of reactants in a chemical reaction(two words)

ester

an organic compound characterized by the functional group R-CO-O-R'

esterification

the production of an ester by the reaction of an alcohol with a carboxylic acid

ether

an organic compound characterized by the functional group R-0-R'

evaporation

the process by which surface particles of liquids escape into the vapor state

excess reactant

reactant remaining when all of some other reactant has been consumed

exergonic

a process having a decrease in Gibbs free energy

exothermic

a change that produces heat

experiment

a test of a hypothesis under controlled conditions

extensive property

a [property] dependent on the amount of matter present(two words)

face-centered cubic

having a [cubic] unit cell with the addition of a particle in the center of each face(three words, hyphenated)

factor-label method

a problem-solving [method] in which units (labels) are treated as factors(three words, hyphenated)

family

the elements composing a vertical column of the periodic table; a group

fat

a biological ester of glycerol and a fatty acid

first ionization energy

the [energy] required to remove the most loosely held electron from an atom(three words)

fission

the splitting of an atomic nucleus into two approximately equal parts

fluid

a material that flows (liquid or gas)

formula

the symbolic representation of a chemical compound

formula mass

the sum of the atomic masses of the atoms in a formula(two words)

formula unit

the amount of a substance represented by its formula(two words)

fractional crystallization

a separation method based on the difference in the solubility of substances(two words)

fractional distillation

a separation method based on the difference in the boiling points of substances(two words)

fractionation

separating a whole into its parts, a mixture into its components

free electrons

the delocalized electrons that are in a metal(two words)

freezing point

the temperature equal to the melting [point] of a pure substance(two words)

frequency

the number of complete wave cycles per unit of time

functional group

an atom other than hydrogen or carbon introduced into an organic molecule(two words)

functional isomers

organic compounds with the same formula, but with the non-hydrocarbon part of the molecule bonded in different ways(two words, plural)

fusion reaction

nuclear [reaction] in which small nuclei are combined to make a larger nucleus(two words)

galvanizing

the coating of iron with a protective layer of zinc

galvanometer

an instrument used to detect an electric current

gamma ray

a quantum of energy of very high frequency and very short wavelength(two words)

gas

the state of matter in which particles are far apart and moving randomly

gas chromatography

a chromatographic method in which a carrier gas (inert) distributes the vapor being analyzed in a packed column(two words)

geometric isomers

compounds with the same formula but different arrangement of substituents around a double bond(two words, plural)

Gibbs free energy

the chemical reaction potential of a substance or system(three words)

gluon

a theoretical massless particle exchanged by quarks

glycogen

a biological (specifically animal) polymer of glucose

Graham's law

The ratio of the relative rates of diffusion of gases is equal to the square root of the inverse ratio of their molecular masses.(two words, possessive)

gray

the unit of absorbed dose of radiation equivalent to 1 J/kg of living tissue

ground state

the [state] of lowest energy of a system(two words)

group

the elements of a vertical column in the periodic table; a family

hadrons

a class of heavy subatomic particles; leptons and _____.(plural)

half-cell

the part of an electrochemical cell in which either the oxidation or reduction reaction is taking place; single electrode in contact with the solution of an electrolyte(two words, hyphenated)

half-life

the length of time necessary for one-half an amount of a radioactive nuclide to disintegrate(two words, hyphenated)

half-reaction

either the oxidation or the reduction part of a redox reaction(two words, hyphenated)

halogen

an element in Group 17(VIIA)

heat

energy transferred due to differences in temperature

Heisenberg uncertainty principle

It is impossible to know exactly both the position and momentum of an electron at the same instant.(three words)

Henry's law

The mass of gas that will dissolve in a specific amount of a liquid varies directly with the pressure.(two words, possessive)

hertz

the unit of frequency equal to one cycle per second

Hess's law

The enthalpy change for an overall reaction is equal to the sum of the enthalpy changes for all steps of the reaction.(two words, possessive)

heterogeneous

composed of more than one phase

heterogeneous catalyst

a [catalyst] in a phase different from that of the reactants(two words)

heterogeneous mixture

a combination of two or more substances that are not uniformly dispersed(two words)

heterogeneous reaction

a [reaction] in which not all reactants are in the same phase(two words)

hexagonal closest packing

having a crystal structure in which space between particles is minimized; found in most metals(three words)

high performance liquid chromatography

a type of column chromatography in which the surface area of the particles in the stationary phase is increased(four words)

homogeneous

uniform throughout

homogeneous catalyst

a [catalyst] in the same phase as the reactants(two words)

homogeneous reaction

a [reaction] in which the reactants are in the same phase(two words)

homologous series

compounds that differ from each other by a specific structural unit(two words)

hybrid orbitals

equivalent [orbitals] formed from orbitals of different energies(two words, plural)

hybridization

the merging of two or more unlike orbitals to form an equal number of identical orbitals in an atom

hydrate

a compound (crystalline) in which the ions are attached to one or more water molecules

hydrated ion

complex ion in which the ligands are water molecules(two words)

hydration

the adhering of water molecules to dissolved ions

hydride ion

a hydrogen atom that has gained an electron; H^-(two words)

hydrocarbon

compound containing only the elements hydrogen and carbon

hydrogen bonding

a very strong dipole-dipole interaction involving molecules in which hydrogen is bonded to a highly electronegative element (N, 0, F)(two words)

hydrogen ion

a hydrogen atom that has lost its electron; H^+; a proton(two words)

hydrolysis

the reaction of a salt with water to form a weak acid or weak base, or both

hydronium ion

H30^+(two words)

hygroscopic

absorbing water from the air

hypothesize

to propose an explanation based on observations

ideal gas

a model in which [gas] particles are mass points and exert no attraction for each other(two words)

ideal gas equation

PV = nRT(three words)

ideal solution

a [solution] in which all intermolecular forces are roughly equal(two words)

immiscible

a property of two liquids that will not dissolve in each other at all

indicator

a weak organic acid whose color differs from that of its conjugate; used to indicate the pH of a solution

induced dipole

a nonpolar molecule that is transformed into a [dipole] by an electric field(two words)

inductive effect

the influence of one functional group on another(two words)

inertia

the tendency of an object to resist any change in its velocity

infrared spectroscopy

the study of the behavior of matter when it is exposed to infrared radiation(two words)

inhibitor

a substance that stops or retards a chemical reaction by forming a complex with a reactant

inner transition elements

those [elements] that fall between numbers 57 and 70 (the lanthanoids) and between numbers 89 and 102 (the actinoids) of the periodic table(three words, plural)

inorganic compound

a molecular [compound] that does not contain carbon(two words)

inorganic substance

a [substance] that is not a hydrocarbon or a derivative of a hydrocarbon(two words)

insulator

a material that does not conduct heat or electricity

intensive property

a [property] of a substance that is independent of the amount of matter present(two words)

interface

the area of contact between two phases

intermediate

the material that is produced from raw materials and processed further to produce some consumer products

intermolecular force

the [force] holding molecules to each other(two words)

internal energy

that [energy] of a system that is altered by the absorption or release of heat and by doing work or having work done on it; energy of a system due to the energy of its constituent particles, but excluding the kinetic and potential energy of the system as a whole(two words)

internuclear distance

the [distance] between the nuclei of two atoms or ions(two words)

intramolecular force

the [force] holding atoms together in a molecule(two words)

ion

an atom or molecule that has gained or lost one or more electrons

ion chromatography

a type of column [chromatography] in which the column is packed with an ion exchange resin(two words)

ion product constant of water

the product of the hydronium and hydroxide ion concentrations in [water] solutions, equal to 1.00 X 10^-14 at 250C(five words)

ionic bond

the electrostatic attraction between ions of opposite charge(two words)

ionic compound

a [compound] that is formed by ionic bonds(two words)

ionic radius

the [radius] of an ion(two words)

ionization constant

the equilibrium [constant] for the ionization of a weak electrolyte(two words)

ionization energy

the [energy] required to remove an electron from an atom(two words)

irreversible thermodynamic change

[change] in volume or pressure in which some energy is lost to an entropy change(three words)

isobaric process

a [process] taking place at constant pressure(two words)

isomer

a substance that has the same molecular formula as another substance, but differs in structure; a substance that exhibits isomerism with another substance

isomerism

the property of having more than one structure for the same formula

isomorphism

condition of two or more compounds having the same crystalline structure

isothermal process

a [process] taking place at constant temperature(two words)

isotope

one of two or more atoms having the same number of protons but different numbers of neutrons

joule

the SI unit of energy; 1 kg-m^2/s^2

Joule-Thomson effect

the cooling [effect] observed when a compressed gas is allowed to expand rapidly through a small opening(three words, hyphenated)

kelvin

the SI unit of temperature; 1/273.16 of the interval between absolute zero and the triple point of water

Kelvin scale

the temperature [scale] with 0 equal to absolute zero and 273.16 equal to the triple point of water(two words)

ketone

an organic compound characterized by the functional group R-CO-R'

kilogram

the SI unit of mass

kinetic energy

the [energy] of an object due to its motion(two words)

kinetic theory

the group of ideas explaining the interaction of matter and energy due to particle motion(two words)

kinetically stable

property of a compound for which the activation energy for decomposition is so high that reaction proceeds too slowly for a change to be detected(two words)

lanthanoid series

fourteen elements beginning with lanthanum in which the arrow diagram predicts the highest energy electrons to be in the 4f sublevel(two words)

law of conservation of energy

[Energy] is conserved in all nonnuclear changes; it cannot be created or destroyed.(five words)

law of conservation of mass

[Mass] is conserved in all nonnuclear changes; it cannot be created or destroyed.(five words)

law of conservation of mass-energy

Although they can be interconverted, the total amount of mass and energy in the universe is constant.(six words, hyphenated)

law of definite proportions

The elements composing a compound are always found in the same ratio by mass.(four words, plural)

law of multiple proportions

The masses of one element that combine with a fixed amount of another element to form more that one compound are in the ratio of small whole numbers.(four words, plural)

law of octaves

The same properties appear every eighth element when the elements are listed in order of their atomic masses.(three words)

Le Chatelier's principle

The [principle] that if a system at equilibrium is subjected to a stress, the system will adjust so as to relieve the stress.(two words, possessive)

length

the distance between two points

leptons

light subatomic particles(plural)

Lewis electron dot diagram

the representation of an atom, ion, or molecule in which an element symbol stands for the nucleus and all inner level electrons while dots stand for outer level electrons(four words)

ligand

a negative ion or polar molecule attached to a central ion in a complex

limiting reactant

the [reactant] that is consumed completely in a chemical reaction(two words)

linear accelerator

a device for accelerating particles in a straight line(two words)

lipid

a biological molecule that is soluble in nonpolar solvents

liquefaction

condensing a gas to a liquid

liquid

the state of matter characterized by its constituent particles appearing to vibrate about moving points

liquid crystal

a substance that has order in the arrangement of its particles in only one or two dimensions(two words)

liter

one cubic decimeter

London forces

another name for dispersion [forces](two words, plural)

macromolecule

a crystal composed of a single molecule with all atoms covalently bonded in a network fashion

magnetohydrodynamics

the study of the behavior of plasmas in magnetic fields

malleability

noun--the property of a substance that allows it to be beaten into thin sheets

manometer

a device for measuring gas pressure

mass

measure of the amount of matter

mass defect

the difference between the mass of an atom and the sum of the masses of the particles composing it(two words)

mass-energy stoichiometry

a problem in which the amount of energy absorbed or released during a reaction can be calculated from the mass of materials(three words, hyphenated)

mass-mass stoichiometry

a problem in which the mass of one substance is provided and the mass of another substance must be calculated(three words, hyphenated)

mass number

the total [number] of protons and neutrons in an atom(two words)

mass spectrometry

an analysis of substances on the basis of the behavior of their ionized forms in magnetic and electric fields(two words)

material

a specific kind of matter

matter

anything that exhibits the property of inertia

mean free path

the average distance a particle travels between collisions(three words)

melting point

the temperature at which the vapor pressures of the solid and liquid phases of a substance are equal(two words)

meson

a subatomic particle classified as a hadron; made of a quark-antiquark pair

metal

an element that tends to lose electrons in chemical reactions

metallic bond

a force holding metal atoms together and characterized by free or delocalized electrons(two words)

metallic conduction

electronic [conduction] within a metal; flow of electrons in a metal(two words)

metalloid

an element that has properties characteristic of a metal and a nonmetal

metastable

the state in which no change will occur unless acted upon by an outside force, but not the most stable state

meter

the SI unit of length

miscibility

the ability of two liquids to dissolve in each other in all proportions

mixture

a material consisting of two or more substances

mobile phase

the fluid containing the mixture to be fractionated in chromatography(two words)

model

an arrangement analogous to, and useful for, understanding a system in nature, but existing only in one's mind

moderator

a substance used to slow neutrons in a nuclear reactor

molal boiling point constant

the change of the boiling point of a solvent in a one-molal solution(four words)

molal freezing point constant

the change of the freezing point of a solvent in a one-molal solution(four words)

molality

a unit of concentration equal to the number of moles of solute per kilogram of solvent

molar heat capacity

the energy necessary to raise the temperature of one mole of a substance by one Celsius degree(three words)

molar mass

the [mass] in grams of one mole of a substance(two words)

molar volume

the [volume] occupied by one mole of a substance; equal to 22.414 10 dm^3 for a gas at standard temperature and standard atmospheric pressure(two words)

molarity

a unit of concentration equal to the number of moles of solute in a cubic decimeter of solution

mole

the Avogadro constant number of objects

mole fraction

a unit of concentration equal to the number of moles of component per mole of solution(two words)

molecular formula

a [formula] indicating the actual number of atoms of each element making up a molecule(two words)

molecular mass

the [mass] found by adding the atomic masses of the atoms comprising the molecule(two words)

molecule

a neutral group of atoms held together by covalent bonds

momentum

the product of mass and velocity

nematic substance

a [substance] that is a liquid crystal with one dimension of order(two words)

net ionic equation

a chemical [equation] with spectator ions eliminated(three words)

network crystal

a [crystal] in which each atom is covalently bonded to all its nearest neighbors, so that the entire crystal is one molecule(two words)

neutral

neither acidic nor basic (electrolytes); neither positive nor negative (electricity)

neutralization

combining equivalent amounts of acid and base

neutralization reaction

the double displacement [reaction] between an acid and a base to produce salt and water(two words)

neutrino

a neutral particle associated with leptons

neutron

a neutral subatomic particle; a hadron

Newtonian mechanics

the laws of [mechanics] applicable in the macroscopic world(two words)

nitrile

an organic compound characterized by the functional group -CN

nitro

the functional group -N02

noble gas

an element in Group 18(VIIIA)(two words)

noble gas configuration

a [configuration] of eight electrons in the outer energy level, except for helium with two electrons in the outer level(three words)

nonmetal

an element that tends to gain electrons in chemical reactions

nonvolatile

does not evaporate easily

normal boiling point

the temperature at which the vapor pressure of a liquid is equal to standard atmospheric pressure(three words)

nuclear force

the [force] holding nucleons together in a nucleus; strong _____.(two words)

nuclear magnetic resonance spectroscopy

the analysis of the structure of a substance by the behavior of its nuclei in a magnetic field(four words)

nuclear reactor

a device engineered to run a controlled nuclear reaction(two words)

nucleic acid

an organic compound containing nitrogenous bases, sugars, and phosphate groups; a compound that either transfers genetic information (DNA) or synthesizes biomolecules (RNA)(two words)

nucleon

a particle found in the nucleus of an atom; a proton or a neutron

nucleotide

a substance containing a nitrogenous base, a sugar, and a phosphate group

nuclide

an atom of a specific energy with a specified number of protons and a specified number of neutrons in its nucleus

observe

to note with the senses, aided or unaided

octahedral

the shape in which six objects are equally spaced about a central object

octane rating

a system of [rating] gasoline based upon the proportions of heptane and 2,2,4-trimethylpentane in the mixture(two words)

octet

an especially stable arrangement of four pairs of electrons in the outer energy level of an atom

octet rule

the tendency of atoms to gain or lose electrons so that they acquire eight electrons in their outer level(two words)

ohm

the SI unit of electrical resistance; one volt per ampere

olefin

an alkene; any hydrocarbon that contains one double bond per molecule; used to manufacture fibers in which the _____ is polermized into a long-chain synthetic polymer; ethylene or propylene are especially used as synethic units

optimum conditions

the [conditions] maximizing the product of an equilibrium reaction(two words, plural)

orbital

the space that can be occupied by 0, 1, or 2 electrons with the same energy level, energy sublevel, and spacial orientation

organic

pertaining to carbon compounds

organic chemistry

the [chemistry] of the compounds of carbon(two words)

organic compound

a [compound] containing carbon, with a very few exceptions(two words)

organic oxidation reaction

a [reaction]; the conversion of an organic compound to carbon dioxide, water, and other appropriate oxides(three words)

organic substance

a [substance] that is a compound that contains the element carbon; a few carbon compounds are considered inorganic(two words)

osmotic pressure

the [pressure] developed across a semipermeable membrane by differential diffusion through the membrane(two words)

oxidation

the loss of electrons

oxidation number

the apparent charge on an atom if the electrons in a compound are assigned according to established rules(two words)

oxidation-reduction reaction

a chemical [reaction] in which electrons are transferred(three words, hyphenated)

oxidizing agent

a substance that tends to gain electrons(two words)

packing

the adsorbent in a chromatographic column

pair repulsion

a model used to predict molecular shape based on the mutual repulsion of electron clouds(two words)

paper chromatography

a chromatographic method that uses paper as the stationary phase; the mobile phase moves by capillary action(two words)

parent chain

the longest continuous [chain] of carbon atoms in an organic compound(two words)

partially miscible

property of two liquids that dissolve in each other to some extent, but not completely(two words)

pascal

the SI unit of pressure; 1 N/m^2

Pauli exclusion principle

No two electrons in an atom can have the same set of quantum numbers.(three words)

peptide bond

an amide link; -CO-NH-(two words)

percent of ionization

the amount ionized divided by the original amount, multiplied by 100(three words)

percent composition

the mass of an element in a compound divided by the mass of the compound, multiplied by 100(two words)

percent yield

the mass of product actually obtained from a chemical reaction divided by the amount of product expected from a mass-mass calculation, multiplied by 100(two words)

period

a horizontal row of the periodic table

periodic law

The properties of the elements are a periodic function of their atomic numbers.(two words)

periodic property

a [property] of elements that appears periodically when the elements are arranged in order of their atomic numbers(two words)

periodic table

a pictorial arrangement ([table]) of the elements based upon their atomic numbers and electron configurations(two words)

petroleum

a raw material consisting chiefly of a complex mixture of hydrocarbons

pH

-log[H30^+]

pH meter

an electronic device for the determination of pH values in solutions(two words)

pH scale

a logarithmic [scale] expressing degree of acidity or basicity(two words)

phase

a physically distinct section of matter with uniform properties set off from the surrounding matter by physical boundaries

phase diagram

a graphical representation of the equilibrium relationships of the phases of a substance(two words)

phenol

C6H5OH; any compound having a hydroxyl group attached to a benzene ring

photoelectric effect

ejection of electrons from a surface exposed to light(two words)

photon

quantum of visible radiant energy

physical change

a [change] in which the same substance is present before and after the change(two words)

physical property

a [property] that can be observed without a change of substance(two words)

pi bond

a [bond] formed by the sideways overlap of p orbitals(two words)

planetary model

the [model] of the atom in which the sun represents the nucleus and the planets represent the electrons(two words)

plasma

a state composed of electrons and positive ions that have been knocked apart by collisions at very high temperatures

pOH

-log[OH^-]

point mass

an ideal gas particle with [mass] but no dimensions(two words)

polar covalent

a bond formed by a shared pair of electrons that are more strongly attracted to one atom than to the other(two words)

polarity

property of a molecule caused by an unsymmetrical charge distribution

polyatomic ion

a group of atoms covalently bonded but possessing an overall charge(two words)

polymer

a very large molecule made from the same simple units repeated many times

polymerization

the formation of a polymer from monomers

polymorphism

the property of a substance whereby it exists in more than one crystalline form

polyprotic acid

an [acid] with more than one ionizable hydrogen atom(two words)

positional isomers

two or more molecules having the same formula but having a functional group in different positions on the parent chain(two words, plural)

positron

the antiparticle of the electron

potential difference

the [difference] in electric potential(two words)

potential energy

the [energy] of an object due to its position(two words)

precipitate

a solid, produced by a reaction, that separates from a solution

precision

the measure of the reproducibility of measurements within a set

pressure

force per unit area

principal quantum number

the [quantum number] designating energy level and electron cloud size(three words)

probability

mathematical expression of "chance" or "odds"

product

a substance produced as the result of a chemical change

protein

a biological polymer of amino acids linked by amide groups

proton

positive nucleon

qualitative

adj.--concerning the kinds of matter present

quantitative

adj.--concerning the amounts of matter present

quantum

a discrete "packet" of energy

quantum mechanics

the laws of [mechanics] concerning the interaction of matter and radiation at the atomic and subatomic level(two words)

quantum number

a [number] describing a property of an electron in an atom(two words)

quantum theory

the [theory] that energy is transferred in discrete units(two words)

quark

a theoretical particle believed to be elementary and a constituent of a hadron

rad

0.01 gray

radiant energy

[energy] being transferred between objects by electromagnetic waves(two words)

radical

a fragment of a molecule; neutral, yet at least one atom lacking its octet of electrons

radioactivity

spontaneous nuclear decay

Raoult's law

The law stating that the vapor pressure of a solution of a nonvolatile solute is the product of the vapor pressure of the pure solvent and the mole fraction of the solvent.(two words, possessive)

rate determining step

the slowest [step] in a reaction mechanism(three words)

raw material

a crude, unprocessed [material] found in nature and used to make intermediates or consumer products(two words)

reactant

a starting substance in a chemical reaction

reaction mechanism

the series of steps through which the reactants pass in being converted to the products in a chemical reaction(two words)

reaction rate

the [rate] of disappearance of a reactant or the rate of appearance of a product(two words)

real gas

a [gas] with particles of finite volume and van der Waals forces between particles(two words)

redox reaction

an oxidation-reduction [reaction](two words)

reducing agent

a substance that tends to give up electrons(two words)

reduction

the gain of electrons

rem

0.01 sievert

reversible change

a [change] that can also go in the opposite direction(two words)

reversible reaction

a [reaction] in which the products may react to produce the original reactants(two words)

reversible thermodynamic change

an ideal [change] in which the difference in pressure is infinitesimal(three words)

Rutherford-Bohr atom

the planetary [atom] model(three words, hyphenated)

salt

a compound formed from a positive ion other than hydrogen and a negative ion other than hydroxide

salt bridge

an ionic solution used to complete an electric circuit in a voltaic cell(two words)

saponification

the reaction of an ester with a strong aqueous base to form a soap and glycerol

saturated

the gaseous phase of a system with equilibrium between a substance and its vapor

saturated compound

a [compound] having only single bonds between carbon atoms(two words)

saturated hydrocarbon

a [hydrocarbon] in which all carbon-carbon bonds are single bonds(two words)

saturated solution

a [solution] in which undissolved solute is in equilibrium with dissolved solute(two words)

science

the systematic investigation of nature

screw dislocation

a crystal defect due to improperly aligned unit cells(two words)

second

the SI unit of time

semiconductor

a substance that conducts electricity, but poorly

semipermeable membrane

a barrier allowing the passage of small ions and molecules but blocking passage of large particles(two words)

shared pair

a [pair] of electrons bonding two atoms together by being shared by the two atoms(two words)

shielding effect

the decrease in the attraction between outer electrons and the nucleus due to the presence of other electrons between them; electron _____.(two words)

SI units

the internationally accepted set of standards for measurements(two words, plural)

side chain

a branch on the parent [chain] of an organic molecule(two words)

sievert

the SI unit used to measure the absorbed dose of radiation; ionizing radiation equal to 100 rem

sigma bond

a [bond] formed by the direct or end-to-end overlap of atomic orbitals(two words)

significant digits

the reliable [digits] in a measurement based on the accuracy of the measuring instrument(two words, plural)

silicates

compounds containing silicon and oxygen(plural)

simple cubic

having a unit cell with one particle centered on each vertex of a cube(two words)

single displacement

a reaction in which one element replaces another in a compound(two words)

smectic substance

a [substance] that is a liquid crystal having two dimensions of order(two words)

solid

the state of matter characterized by particles that appear to vibrate about fixed points

solubility

the quantity of solute that will dissolve in a specified amount of solvent at a specific temperature

solubility product constant

the equilibrium [constant] for the dissolving of a slightly soluble salt(three words)

solute

the substance present in lesser quantity in a solution

solution

a homogeneous mixture composed of solute and solvent

solution equilibrium

the state in which solute is dissolving at the same rate that solute is coming out of solution(two words)

solvation

the attaching of solvent particles to solute particles

solvent

the substance present in the greater amount in a solution

space lattice

the arrangement pattern of the unit cells in a crystal(two words)

specific heat

the amount of energy required to raise the temperature of one gram of a substance by one Celsius degree(two words)

specific rate constant

a [constant] relating the rate of a reaction to reactant concentrations(three words)

spectator ion

an [ion] present in a solution but not taking part in a chemical reaction(two words)

spectroscopy

the study of the interaction of matter and radiant energy

spectrum

a unique set of wavelengths absorbed or emitted by a substance

spin

a property of subatomic particles corresponding to rotation on an axis

spontaneous

occurring without outside influence

square planar

the arrangement in which four objects are at the corners of a square around a fifth object in the center(two words)

stability

the ability of a substance to remain undecomposed

standard atmospheric pressure

101.325 kPa(three words)

standard solution

a [solution] whose concentration is known with a high degree of accuracy(two words)

standard state

thermodynamic reference conditions, 25.0 C, 101.3 kPa, 1M(two words)

standard temperature

0 degrees C for gases; 25 degrees C for thermodynamics(two words)

starch

a biological (specifically plants) polymer of glucose

state

the particle arrangement in a phase as solid, liquid, gas, or plasma

state function

a thermodynamic quantity that is determined solely by the conditions, not the method of arriving at those conditions(two words)

stationary phase

the adsorbent in chromatography(two words)

stoichiometry

mass and volume relationships in chemical changes

STP

standard temperature and atmospheric pressure (273 K and 101.325 kPa)

strong acid

a completely ionized acidic electrolyte(two words)

strong base

a completely ionized basic electrolyte(two words)

structural isomers

two or more compounds with the same formula but differing arrangements of the parent carbon chain(two words, plural)

subatomic particle

a [particle] smaller than an atom(two words)

sublevel

energy subdivision of an energy level

sublimation

the change directly from solid to gas

substance

a material with a constant composition

substituent

a hydrocarbon branch or functional group attached to the parent chain of an organic compound

substitution reaction

a [reaction] of organic compounds in which a hydrogen atom or functional group is replaced by another functional group(two words)

supercooled liquid

a [liquid] cooled below its normal freezing point without having changed state to the solid form(two words)

supersaturated solution

a [solution] containing more solute than would a saturated solution at the same temperature(two words)

surface tension

the apparent "skin" effect on the surface of a liquid or solid due to unbalanced forces on the surface particles(two words)

suspension

a dispersion of particles > 100 nm in a continuous medium

synchrotron

a device for accelerating particles in a circular path

synthesis

the formation of a compound from two or more substances

synthetic element

an [element] not occurring in nature(two words)

system

that part of the universe under consideration

technology

the practical applications of scientific discoveries

temperature

a measure of the average kinetic energy of the particles composing a material

temporary dipole

a [dipole] formed from a nonpolar molecule for a brief period due to the presence of an electric field(two words)

ternary

composed of three elements

ternary acid

an [acid] containing hydrogen, usually oxygen, and one other element(two words)

tetradentate

describing a ligand that attaches to the central ion in four locations

tetrahedral

adj.--four objects equally spaced in three dimensions around a fifth object

theory

an explanation of a phenomenon

thermodynamic stability

the [stability] of a substance due to a positive change in the Gibbs free energy for the decomposition of the substance(two words)

thermodynamics

the study of the flow of energy in systems

thermometer

a device for measuring temperature

thin layer chromatography

a method of [chromatography] utilizing an adsorbent spread over a flat surface in a thin layer(three words)

time

the interval between two occurrences

titration

a laboratory technique for measuring the relative concentrations of solutions

tracer

a radioactive nuclide used to follow the progress of a reaction or a process

transistor

an electronic device made from a doped semiconductor

transition element

an [element] whose highest energy electron is in a d sublevel(two words)

transmutation

the conversion of one element into another

transuranium element

an [element] with an atomic number greater than that of uranium(two words)

triad

a group of three elements with similar properties

tridentate

a ligand that attaches to the central ion in three locations

tripeptide

three amino acids joined by amide links

triple bond

a [bond] in which two atoms share three pairs of electrons(two words)

triple point

the temperature and pressure at which all three states of a substance are in equilibrium(two words)

Tyndall effect

the scattering of light by colloidal or suspended particles(two words)

ultraviolet spectroscopy

the study of the interaction of matter and ultraviolet radiation(two words)

unit cell

the simplest unit of repetition in a crystal(two words)

unsaturated compound

an organic [compound] containing one or more multiple bonds(two words)

unsaturated hydrocarbon

[hydrocarbon] containing one or more multiple bonds(two words)

unsaturated solution

a [solution] containing less than the saturated amount of solute(two words)

unshared pair

a [pair] of electrons in an orbital belonging to one atom(two words)

van der Waals forces

weak [forces] of attraction between molecules(two words, plural)

van der Waals radius

[radius] of closest approach of a nonbonded atom(two words)

vapor

the gaseous state of a substance that is liquid or solid at room temperature and pressure

vapor equilibrium

the [equilibrium] state between a liquid and its vapor(two words)

vapor pressure

the [pressure] exerted by a vapor in equilibrium with its liquid(two words)

velocity

the speed and direction of motion

viscosity

the resistance of a liquid to flow

visible spectroscopy

the study of the interaction of matter with visible radiation(two words)

vitamin

a group of biochemicals that are necessary for some enzymatic reactions to take place

volatile

an easily evaporated liquid

volt

the SI unit of electric potential difference

voltaic cell

a [cell] in which a chemical reaction generates an electric current (two words)

wave

a periodic disturbance in a medium

wave equation

the [equation] describing the behavior of the electron as a wave(two words)

wavelength

the distance between two successive crests of a wave

wave-particle duality of nature

All particles have wave properties and all waves have particle properties.(five words, hyphenated)

weak acid

a slightly ionized acidic electrolyte(two words)

weak base

a slightly ionized basic electrolyte(two words)

weak forces

an attraction of molecules for each other through the action of dipoles(two words, plural)

weight

the gravitational attraction of Earth or a celestial body for matter

work

a force moving through a distance