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Calorie the amount of energy requird to raise the temperature of one gram of water one degree Celsius, equal to 4.184 J
Calorimeter a devicie used to measure energy changes accompnying chemical and physical changes by observing temperature alterations
Capillary action the spontaneous rising of a liquid in a narrow tube
Carbohydrate a polyhydroxyl ketone or polyhydroxyl aldehyde or a polymer composed of these
Carbon steel an alloy of iron containing up to about 1.5% carbon
Carboxyhemoglobin a stable complex of hemoglobin and carbon omonxide that prevents normal oxygen update in the blood
Carboxyl group the -COOH group in an organic acid
Catalyst a substance that increases the rate of a chemical reaction without being consumed itself
Catalytic converter a system to catalyze teh combusion of carbon monoxide and unburned hydrocarbons in automobile exhaust gases
Cathode the electrode in a galvanic cell at which reduction occurs
Carhode rays streams of electrons emitted from the cathode of a discharge tube
Cathodic protection a method in which an active metal, such as magnesium, is connected to steel in order to protect it from corrosion
Cation a positive ion
Cell potental the driving force in a galvanic cell that pulls electrons from the reducing agent in one compartment to the oxidizing agent in the other
Ceramic a nonmetallic material made from clay and hardened by firing at high temperature; it contains minute silicate crystals suspended in a glassy cement
Chain mechanism a reaction mechanism in which an intermediate reactant consumed in an early step is regenerated in a later step
Chain reaction a self-sustaining fission process caused by the production of neutrons that proceed to split other nuclei
Chalcogens the elements of group 6A of the periodic table
Charge density the charge per unit volume of an ion
Charles' Law the volume of a given sample of gas at constant pressure is directly proportional to the temperature in kelvins
Chelate a coordination complex containing rings formed by polydentate ligands
Chemical adsorption the attachment of molecules to a surface by attractions of the strength of reactants and products are constant
Chemical bond the energy that holds two atoms together in a compound
Chemical change the change of substances into other substances through a reorganization of the atoms; a chemical reaction
Chemical equation a representation of a chemical reaction showing the relative numbers of reactant and product molecules
Chemical equilibrium a dynamic reaction system in which the concentrations of all reactants and products remain constant as a function of time
Chemical kinetics the area of chemistry that concerns reaction rates
Chemical property a preoperty observed when a substance undergoes a transformation into one or more new substances
Chemical stoichiometry the calculation of the quantities of material consumed and produced in chemical reactions
Chemiluminescence the emission of light from an excited state produced by chemical reaction rather than by irradiation
Chiral molecules molecules that are not superimposable on their mirror images
Chlor-alkali process the process for producing chlorine and sodium hydroxide by electrolyzing brine in a mercury cell
Chromatography the separation of a liquid or gaseous mixture by passage over an adsorbent so that each component becomes adsorbed separately
Chromophore the group of atoms in a molecule responsible for teh adsorption of radiation
Closed system a system that can exchange only energy with its surroundings
Coagulation the destruction of a colloid by causing particles to aggregate and settle out
Codons organic bases in sets of three that form the genetic ode
Colligative properties the properties of solutions - vapor pressure, boiling point, freezing point, and oxmotic pressure -- that are independent of the identity of the solute but are determined by the number of particles in the solution
Collision model a model based on the idea that molecules must collide to react; used to account for the observed characteristics of reaction rates
Colloid a suspension of particles in a dispering medium
Combustion reaction the vigorous and exothermic reaction that takes place between certain substances, particularly organic compounds and oxygen
Common ion the ion of a soluble salt that is the same as the ion formed by the dissociation of a weak acid or base or by the dissolution of a slightly soluble salt
Common ion effect the shift in an eqiulibrium position caused by the addition or presence of an ion involved in the equilibrium reaction
Complete ionic reaction an equation that shows all substances that are strong electrolytes as ions
Complex ion an ion resulting from the coordination of several Lewis-base ligands with a metal ion
Compound a substance with constant composition that can be broken down into elements by chemical processes
Compressible capable of being reduced in volume through exertion of external pressure
Concentration the ratio of the amount of solute to the amount of solvent or solution
Concentration cell a galvanic cell in which both compartments contain the same components, but at different concentrations
Condensation the process by which vapor molecules reform a liquid
Condensation polymerization a type of polymerization in which the formation of a small molecule, such as water, accompanies the extension of the polymer chain
Condensation reactions a reaction in which two molecules are joined, accompanied by the elimination of a water molecule
Condensed states liquids and solids
Conduction bands the band ofmolecular orbitals in a metal through which electrons are free to move
Conjugate Acid the acid formed by the addition of proton to a base
Conjugate Base the base formed by the removal of a proton to an acid
Continuous spectrum a spectrum containing radiation of all wavelengths
Contributing structures the different Lewis structures that can be written for a molecule exhibiting resonance
Control rods rods in a nuclear reactor composed of substances that absorb neutrons. These rods regulate the power level of the reactor
Coordinate covalent bond a metal-ligand bond resulting from the interaction of a Lewis base (the ligand) and a Lewis acid (the metal ion)
Coordinate compound a compound composed of a complex ion and counter ions sufficient to give no net charge
Coordination isomerism isomerism in a coordination compound in which the composition of the coordination sphere of the metal ion varies
Coordination number the number of bonds formed between the metal ion and ligands in a complex ion
Copolymer a polymer formed from the polymerization of more than one type of monomer
Core electron an inner electron in an atom; one not in the outermost (valence) principle quantum level
Corrosion the process by which metals are oxidized in the atmosphere
Coulomb the quantity of electricity transferred by a current of one amp in one second
Coulomb's Law the force acting between a pair of charged particles is directly proportional to the product of their charges and inversely proportional to the square of the distance between them
Coulometer an electrolysis cell used to measure the quantity of electricity flowing concurrently through a second electrolysis cell connected in series
Counter ions anions or cations that balance the charge on the complex ion in a coordination compound
Covalent bonding a type of bonding in which electrons are shared by atoms
Cracking a process whereby large molecules of petrolum components are broken down to smaller ones by breaking carbon-carbon bonds
Critical mass the mass of fissionable material required to produce a self-sustaining chain reaction
Critical point the temperature and pressure above which a liquid state cannot exist
Critical pressure the minimum pressure required to produce liquefaction of a substance at the critical temperature
Critical reaction a reaction in which exactly one neutron from each fission event causes another fission event, thus sustaining the chain reaction
Critical temperature the temperature above which vapor cannot be liquefied no matter what pressure is applied
Crosslinking the existence of bonds between adjacent chains in a polymer, thus adding strength to the material
Crust the outermost thin layer of the earth
Crystal field theory a bonding model for coordination complexes picturing ligands as charges that split the energy levels of the d orbitals of the metal atom or ion
Crystalline solid a solid with a regular arrangement of its components
Cubic closest packed structure a solid modeled by the closest packing of spheres with an abcabc arrangement of layers; the unit cell is face-centered cubic
Cyanidation a process in which crushed gold ore is treated with an aqueous cyanide solution in the presence of air to dissolve the gold. Pure gold is recovered by reduction of the ion to the metal
Cyclotron a circular device for accelerating ions for use in nuclear reactors
Cytochromes a series of ion-containing specis composed of heme and a protein. Cytochromes are the principle electron-transfer molecules in the respiratory chain
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