普通化學(xué)英漢術(shù)語

普通化學(xué)英漢術(shù)（GeneralChemistryIntroduction:Matterand Atoms,Molecules,and Stoichiometry:CalculationswithChemicalFormulasand AqueousReactionsand ElectronicStructureof PeriodicPropertiesofthe BasicConceptsofChemical MolecularGeometryandBonding IntermolecularForces,Liquids,andSolids

Modern Propertiesof Chemical Chemical Acid-Base AdditionalAspectsofAqueous Chemistryofthe Chemical Chemistryofthe Metalsand ChemistryofCoordination thecompositionpropertiesandtransformationsofmassthephysicalmaterialoftheuniverse.atommoreatoms.mattercanassume:solid,liquid,andgas.specificshape.adefinitevolume.mixture（混合物）Acombinationoftwoormorechemicalidentity.heterogeneous（不均勻的）Havingdiversecompositionanddistinctproperties.

moreelementsunitedchemicallyindefinitethatstatesthattheelementalcompositionofapurealsocalledthelawofdefiniteproportions.statesthattheelementalcompositionofapurealsocalledthelawofconstantcomposition.thepassageofcurrentunderasufficientexternalreactionsoccurarecalledelectrolyticcells.substanceforexamplecolorandfreezingpoint.howthesubstancereacts,orchangesintoothertheamountofmaterialconsidered;forexample,anobject.Itmeasuresthe ofanobjecttobeingmoved.InSIunits,massismeasuredinoneormoresubstancesareconvertedintoothersubstancesalsocalledchemicalreactions.oneormoresubstancesareconvertedintoothersubstancesalsocalledchemicalchanges.fromagastoaliquid.inscience.amongseveralmeasurementsofthesamety;thereproducibilityofameasurement.（準(zhǔn)確度）Ameasureofhowcloselyindividualthelastdigitwhichisuncertain. ysis（因次分析）Amethodoffinalanswerofacalculationhasthedesiredunits.converttheunitsofmeasurement.

compoundisalwaysthesame,regardlessofitsscientificlawstatingthatthetotalmassoftheproductsofachemicalreactionisthesameasthetotalmassofthereactants,sothatmassremainsconstantduringthereaction.thatiftwoelementsAandBcombinetoformmorethanonecompound,themassesofBthatcancombinewithagivenmassofAarerelatedbyfactorsofsmallwholenumbers.neutrons,andelectronsthataresmallerthananthatareproducedwhenahighvoltageisappliedtoelectrodesinanevacuatedtube.electron（）:Anegativelychargeditisapartofallatoms.Anelectronhasamass1/1836timesthatofaproton.electroniccharge（）:Thenegativechargecarriedbyanelectron;ithasamagnitudeof1.602×10-19C.TheModernViewofAtomicStructurenucleus（原子核）Theverysmallverydense,ofprotonsandproton（質(zhì)子）:Apositivelychargedsubatomicparticlefoundinthenucleusofanatom.samemassasaproton.angstrom（埃）Acommonnon-SIunitoflength,denotedm.atomicmassunit(amu)（原子質(zhì)量單位）:Aunitbasedonthevalueofexactly12amuforthemassoftheisotopeofcarbonthathassixprotonsandsixneutronsinhenucleusofanatomofanelement.isotopes（）Atomsofthesameandthereforehavingdifferentmasses.ofprotonsandneutronsintheatom.

theperiodictableelementswithinthesamegrouporfamilyexhibitsimilaritiesintheirchemicalbehavior.

nonmetalsdifferfrommetalsintheirphysicaland(metal) nonmetalsdifferfrommetalsintheirphysicalandchemicalproperties.thediagonallineseparatingthemetalsfromthenonmetalsintheperiodictablethepropertiesofandnonmetals.groups1-8A. twoormoreatoms.therelativeproportionsofatomsofthedifferentelementsinasubstance.inonemoleculeofasubstance.andtheirrelativenumbersinasubstance. charged,dependingonwhetherelectronsarelost(positive)orgained(negative)bytheatoms.lostorgainedoneormoreelectronsto electricallycharged.groupoftwoormoreatoms.:

containsoneormoreoxygenatoms.ofthereactantsandproductsabalancedchemicalequationcontainsequalnumbersofatomsofeachelementonbothsidesofthereactant（應(yīng)物）Astartingsubstanceinachemicalreactionitappearstotheleftofthearrowinachemicalequation.arrowinachemicalequation.Thislaw eachtypeofatomonbothsidesofthearrow.Compound（化合物）: arrowreactantsandtherightsideofthearrowoftheperiodictableelementswithinthesameamatch.statesofcertainatomschange.theperiodictable.positionreaction（分解反應(yīng)）Areactstogivetwoormoreproducts.inonemoleculeofasubstance.andtheirrelativenumbersinasubstance.dictatedbythebalancedequation.(experimental)yieldofaproducttoitstheoretical(calculatedyieldmultipliedby100.AqueousReactionsandSolutionpositionahomogeneousmixture.greateramount.formasolution;itisnormallythecomponentofasolutionpresentinthesmalleramount.isthesolvent.ionizeinwaterandconsequentlygivesapleyionizedinsolutionforexamplestrongacidsstrongbasesandmostsalts.partlyionizesinsolution.Usedforioniccompoundsthatcomeapartwhen

theproductsisinsoluble.in,andseparatesfromasolution.inwhichtheformulaforeachsubstanceiswrittenwithoutregardforwhetheritisanelectrolyteorapredominantlyasionsareseparatedandwrittenasseparateions.thecompleteionicequation.forasolutionreactioninwhichsolublestrongpartlyionizesinsolution.Acid-Base:proton)andhenceincreasestheconcentrationofH+(aqwhenitdissolvesinwater.anexcessofOH-(aqionswhenitdissolvesinwater.salt（鹽）AnioniccompoundformedbyreplacingoneormoreHofanacidbyothercations.whichanacidandabasereactinstoichiometricallyequivalentamounts;theneutralizationreactionbetweenanacidandametalhydroxideproduceswaterandasalt.chemicalreactioninwhichtheoxidationstatesofcertainatomschange.losesoneormoreelectrons.gainsoneormoreelectrons.negativecharacterofthatatom.ofdecreasingeaseofoxidation.:agiventyofsolventorsolution.molarityexpressedasmolesofsoluteperliterofsolution;abbreviatedM.unknownconcentrationwithoneofknownconcentrationastandardsolution).reactscompleywiththesolutepresentinthesolutehasjustreactedwithallthesolutepresentinheat（熱）Theflowofenergyfromabodyathigherplacedinthermalcontact.jouleJ)（焦耳）TheSIunitofenergyoutsideofthesystemofinterest.possessesbyvirtueofitsmotion.withrespecttoanotherobject.changeininternalenergyEofasysteminany

surroundings:E=q+ernalenergy（內(nèi)能:Thetotalenergypossessedbyasystem.thatisdeterminedbythestateorconditionofthesystemandnotbyhowitgottothatstateor=E+PV;theenthalpychange, thatoccursatconstantpressureistheheatevolvedorsystemandnotbyhowitgottothatstateorforexample,density.mattercanassumesolidliquidandgas.heatofsolution（溶解熱）Theenthalpyofheatproducedinchemicalandphysicalofmatterbyonedegree(CelsiusorKelvin).Theheatcapacityof1gofasubstancetheheatrequiredtoraisethetemperatureof1gofasubstancebyonedegreeCelsiusorKelvin).onedegree(CelsiusorKelvin).calorimetrevolutionofheat.

universethatwesingleoutforstudy.thatliesoutsidethesystemofinterest.changeininternalenergy,E,ofasysteminanyplusthework,w,doneonthesystembyits E=q+w.bombcalorimeter（彈式量熱計(jì)）Adeviceforsubstanceunderconstant-volumeconditions.ofinterest.

speedof3.00×108m/s.energythatmaybeabsorbedoremitted;themagnitudeofradiantenergyishv.blackbodyradiation（）:Theelectromagneticradiantemittedbyahotobject.anenergyequaltohv.byanradiationatonlycertainspecificwavelengths. fenthalpythat theirstandardstates.whicharepresentlyourmajorsourcesofenergy.:compoundscarbondioxideandwater.by1度from14.5?Cto15.5度。Arelatedunitisthejoule:1cal=4.184J.asubstanceiscombusted.gaseoushydrocarboncompoundscomposedofhydrogenandcarbon.liquidcomposedofhundredsofhydrocarbonsandotherorganiccompounds.coal（煤）Anaturallyoccurringsolidcontaininghydrocarbonsofhighmolecularweightaswellas

stable,thegroundstate.thewavecharacteristicsofaparticle.momentum（動(dòng)量）Theproductofthemassm,andvelocity,v,ofaparticle.statingthereisaninherentuncertaintyinthethepositionandmomentumofaparticle.Thisuncertaintyissignificantonlyforextremelysmallparticlessuchaselectrons.ofanallowedenergystate(anorbital)foratom;itisusuallysymbolizedbytheGreek.representstheprobabilitythatanelectronwillbefoundatagivenpointinspace.electrondensity（電子密度）:Theprobabilityoffindinganelectronatanyparticularpointinanatom;thisprobabilityisequalto,thesquareofthewavefunction.electroninthequantummechanicalmodelofthenode（節(jié)點(diǎn)）AlocusofpointsinanatomatwhichtheorbitalFigure6.19isasphericalsurface.effectivenuclearcharge（有效核電荷）Thenetpositivechargeexperiencedbyanelectroninabytheotherelectronsintheatom.electronspiniszed.2spinitmayhavevaluesofor1.2samefourquantumnumbersnlmlandmsAsathantwoelectronsinanyoneatomicorbital.thedorbitalsarepartiallyoccupied;alsocalledtransitionmetals.inwhichthe4?/i>subs isonlypartiallyoccupied.5?/i>orbitalsareonlypartiallyoccupied.7.3Ionizationremoveanelectronfromagaseousatomwhentheatomisinitsgroundstate.7.4Electronthatoccurswhenanelectronisaddedtoagaseousatomorion.7.6GroupTrendsfortheActiveperiodictable.2Aintheperiodictable.7.7GroupTrendsforSelected

periodictable.BasicConceptsofChemicalOctetRulechargedions.Theionsareformedfromatomsbytransferofoneormoreelectrons.ormoreatomsbyasharingofelectrons.bondingelectronsarerelativelyfreetomovethroughoutthethree-dimensionalstructure.symblanelementwithadotforeachvalenceelectron.symbolforanelementwithadotforeachvalencemoleculeshavingthesamenumberofelectrons.atomstendtopossessorshareatotalofeight latticeenergy（晶格能）Theenergyrequiredtoseparatedcompleytheionsinanionicsolid.othermeasurableproperties.covalentbondinginamoleculethatisdrawnusingofdots.Onlythevalence-s electronsareshown.electronpair.moreelectronpairs.electronpairs.bondinwhichtheelectronsaresharedequally.inwhichtheelectronsarenotsharedequally.toitself.thedipolemoment（偶極矩）:Ameasureoftheinpolarmolecules.dipole（偶極子）Amoleculewithoneendhavingaslightnegativecharge;apolarmoleculeDrawingLewiselectronsinanisolatedatomminusthenumberofresonancestructuresinsuchaninstanceare"averaged"togiveacorrectdescriptionofthereal8.9StrengthsofCovalentbondenthalpy（鍵能）Theenthalpychange,H,isinthegasphase.oftwobondedatoms.valence-selectron-pairrepulsion(VSEPR)model（價(jià)層電子對(duì)互斥模型）:Amodelthataccountsforthegeometricarrangementsofsharedandoftherepulsionsbetweenelectronpairs.irofelectronsthatissharedbytwoatoms.alsocalledalonepair. existingdefinition.

thereisnoexistingdefinition.inspaceoftheatomsofamolecule.thetwoatomsofacovalentbond.:bondinginwhichanelectron-pairbondistwogroundstate.sigmabond（σ鍵）:Acovalentbondinwhichdensityisconcentratedaboveandbelowthelinejoiningthebondedatoms.advancingscientificknowledgebymakinghypothesesandtheories.thataccountsfortheallowedstatesforelectronsininanatomAmolecularorbitalmaybeclassifiedaswithrespecttotheinternuclearaxis.bondingmolecularorbital（成鍵分子軌道）Amolecularorbitalinwhichtheelectrondensityistheseparateatomicorbitalsfromwhichitforms.molecularorbitalinwhichelectrondensityisarelessstable(ofhigherenergy)thanbondingmolecularorbitals.orbitalsfromwhichtheyarederived.Alsocalledamolecularorbitaldiagram.possessesifitcontainsoneormoreunpairedAparamagneticsubstanceisdrawnintoaweaklyrepelledfromamagneticfield.SIunitspressureisexpressedinpascalsPa).as760torrorinSIunits101.325kPa.to760torr;1atm101.325kPa.Boyle'slaw（Boyle定律）Alawstatingthatatpressureofagivenamountofgasisaconstant.gasisproportionaltoabsolutetemperature.thevolumeofagasmaintainedatconstanttyofthegas.

proportionalityintheideal-gasequation.idealgas（理想氣體）Ahypotheticalgaswhosepressurevolumeandtemperaturebehavioriscompleydescribedbytheideal-gasequation.況—標(biāo)準(zhǔn)溫度和壓力）Definedas0°Cand1atmAlawstatingthatthetotalpressureofamixtureofexertifitwerepresentalone.particulargasinamixture.identifythecomponent.assumptionsaboutthenatureofgasesTheseyieldtheideal-gasequation.squarerootoftheaverageofthesquaredspeedsofthegasmoleculesinagassample.throughanother.orificeorhole.squarerootofedbyagasmoleculebetweencollisions.attractionandforthevolumesoccupiedbythegasmoleculesthemselves.lowtemperaturesandhighpressures.ion-dipoleforce（誘導(dǎo)力）Theforcethatexistsbetweenanionandaneutralpolarmoleculethatpossessesapermanentdipolemoment.betweenpolarmolecules.Londondispersionforce色散力或倫敦力):Thetemporarydipoleononeatomcaninduceasimilarattractedtoeachother.ThisattractiveinteractioniscalledLondondispersionforce.ermolecularattractionsbetweenmoleculescontaininghydrogenbondedtoanelectronegativenitrogenorfluorine.viscosity（粘度）:Ameasureofthe toflow.surfacearea.aliquidrisesinatubebecauseofacombinationofadhesiontothewallsofthetubeandcohesionbetweenliquidparticles.phasechanges（相變）:TheconversionofasubstancefromonestateofmattertoanotherTheandvaporizationandcondensationliquidgas).

formeltingasolid.heatofvaporization（蒸發(fā)熱）:Theenthalpychange,Hforvaporizingaliquid.heatofsublimation（升華熱）Theenthalpycriticaltemperature（界溫度）ThehighesttemperatureatwhichitispossibletoconvertthegaseousformofasubstancetoaliquidThecriticaltemperatureincreaseswithanincreaseinthemagnitudeofintermolecularforces.vaporinequilibriumwithitsliquidorsolidphase.whichopposingprocessesoccuratthesamerate.1atmpressure.ofasubstanceasafunctionoftemperatureandliquidandgasphasescoexistinequilibrium.point1atmpressure.1atmpressure.arrangementlacksaregularlong-rangepattern.inanydirectionthroughthesolid.reproducesthestructureoftheentirecrystalwhenrepeatedindifferentdirectionsinspace.Itisthehexagonalclosepacking（六方最密堆積）:cubicclosepacking（心立方最密堆積）:Afirstlayer.coordinationnumber（配位數(shù)）Thenumberofthenumberofdonoratomstowhichitisbonded.pointofthesolidform.Bycontrast,innonliquidmeltingiscompleyunordered.whichtheendsofthemoleculesarenotaligned.Aliquidcrystalinwhichthemoleculesarealignedendsofthemoleculesaligned.Thereareseveraldifferentkindsofsmeticphases.thatalignthroughastackingofthemoleculardiscs.Theindividualmoleculesformingthepolymerarecalledmonomers.formapolymer.inwhichonereactioninitiatesthenext.molecularmassformedbythejoiningtogetherorpolymerarecalledmonomers.

:reactioninwhichasmallmolecule(suchasamoleculeofwater)issplitoutfrombetweentworeactingmolecules,asforexamplebetweenanorganicacidandanaminefunction. polymerization（縮聚）:Polymerizationinwhichmoleculesarejoinedtogetherthroughcondensationreactions.plasticizers（增塑增韌劑）:Organicmoleculesaddedtoapolymertoreducemorepliable.betweenpolymerchains.chemicalstepsfollowedbycontrolledheating.presentinmuchgreatertythantheothersandactsastheprimaryhostmatrixfortheother"frictionless"flowofelectronsthatoccurswhenasubstancelosesall totheflowofbelowwhichasubstanceexhibitsTc（臨界溫度）:Thetemperaturebelowwhichasubstanceexhibitssuperconductivity.piezoelectricmaterial（壓電材料）:Apotentialalongitslengthwhensubjectedtoamechanicalstress.Quartzisawell-knownpiezoelectricmaterial.thinfilm（）:Afilmdepositedonanunderlyingsubstratetoprovidedecorationorprotectionfromchemicalattackortoenhanceadesirableproperty,suchasreflectivityelectricalconductivity,color,orhardness.vacuumdeposition（真空沉積）:Amethodofformingthinfi inwhichasubstanceis positionandthendepositedontheobjecttobe

thecathodeinahigh-voltagegaseousdischargeofaninertgas.chemical-vapordeposition（化學(xué)蒸汽沉積）Aofchemicalreactiontoformthefilm.positionahomogeneousmixture.greateramount.formasolution;itisnormallythecomponentofasolutionpresentinthesmalleramount.solvation（溶劑化）Theclusteringofsolventmoleculesaroundasoluteparticle.soluteanddissolvedsoluteareinequilibrium.dissolvesinagiventyofsolventatagiventemperaturetoformasaturatedsolution.containinglesssolutethanasaturatedsolution.containingmoresolutethanasaturatedsolution.miscible（混溶的）LiquidsthatmixinallHenry'slaw（Henry定律）AlawstatingthatthetothepressureofgasoverthesolutionCgkPg.partspermillion（ppm百萬分之一）:Theperliterofsolutionforaqueoussolutions.solution;equalsmicrogramsofsoluteperliterofsolutionforaqueoussolutions.solvent(vapor-pressurelowering,freezing-pointRaoult'slaw（Raoult定律）Alawstatingthat

P°,timesthemolefractionofasolventinthesolution,Xa:Pa=XaP°.idealsolution（理想溶液）AsolutionthatobeysRaoult'slaw.常數(shù)）:(Kb)Aconstantcharacteristicofaparticularsolventthatgivesthechangeinboilingpointasa降低常數(shù)）:(Kf)Aconstantcharacteristicofapointasaosmosis（）:Thenetmovementofsolventsolutionwithgreatersoluteconcentration.osmoticpressure（滲透壓）Thepressurethatmustbeappliedtoasolutiontostoposmosisfrompuresolventintothesolution.:largerthannormalsolutesbutsmallenoughtoremainsuspendedinthedispersingmedium.smallenoughtoremainsuspendedinthedispersingmediumhydrophilic（親水性）:Chemicalkinetics（化學(xué)動(dòng)力學(xué)）:Theareaofchemistryconcernedwiththespeedsorrates,atwhichchemicalreactionsoccur.reactionrate（反應(yīng)速率）:Thedecreaseinconcentrationofareactantortheincreaseinconcentrationofaproductwithtime.anintervaloftime.TheDependenceofRateonConcentrationrateconstant（）Aconstantofproportionalitybetweenthereactionrateandtheconcentrationsofreactantsthatappearintherateratelaw（速率定律）:Anequationthat

(andsometimesofproductsalso).concentrationofareactantisraisedinaratelaw.TheChangeofConcentrationwithTimehalf-life（半衰期）Thetimerequiredforthehalfitsinitialvalue;thetimerequiredforhalfofwhichtheoverallreactionorder(thesumoftheconcentration-termexponentsintheratelawis2.factorsinfluencingreactionratesintermsoftheenergiesexceedingtheactivationenergyandtheprobabilitythatthecollisionsoccurwithsuitableformationofproducts.Theparticulararrangementofreactantandproductmoleculesatthepointof umenergyintherate-determiningstepofareaction.)thepotential-energybarrierasareactionproceedsfromreactantstoproducts.forreaction.inrelativepositionsoftheatomsasthereactionsingleeventorstep.thatparticipateasreactantsinanelementarythatinvolvesasinglemolecule.bimoleculr:

reactionthatinvolvesthreemolecules.rate-determiningstep（控制步驟）:Theoneelementarystepofamultistepmechanismandconsumedinanother;itisneitherareactantnoranultimateproductoftheoverallreaction.catalystspeedofachemicalreactionwithoutitselfundergoingapermanentchemicalchangeinthecatalyt:speedofachemicalreactionwithoutitselfundergoingapermanentchemicalchangeinthe劑）:Acatalystthatisinadifferentphasefromthatofthereactantsubstances..undergoesareactionattheactivesiteinaninwhichthesubstratemoleculeispicturedasfittingratherspecificallyintotheactivesiteontheenzymeItisassumedthatinbeingboundtotheproductsofareactionfromthereactantsequalstherateofformationofthereactantsfromthereactantsandproductsremainconstant.andconditionsoftemperatureandpressureformationofNH3fromH2andN2.lawofmassaction（質(zhì)量作用定律）The

accordingtowhichtheequilibriumconstantisandproducts,inaccordancewiththebalancedchemicalequationforthereaction.equilibriumexpression（平衡表達(dá)式）TheobtainedbymultiplyingtheconcentrationsoftheequationThedenominatorsimilarlycontainstheoftheequation.valueoftheequilibriumexpressionforasystemat:moredifferentphasesforexamplebetweenagasandasolidorbetweenasolidandaliquid.ApplicationsofEquilibriumConstantsobtainedwhenconcentrationsofreactantsandK;otherwiseQstatingthatwhenwedisturbasystematchemicalAcid-Base16.2Br?nsted-LowryAcidsandsubstancethatactsasaprotonsubstancethatactsasaprotonacceptor.anacidorabase.lossofaprotonfromaBr?nsted-Lowryacid.

abase,suchasH2Oand ,thatdifferonlyinthepresenceorabsenceofaproton.additionofaprotontoaBr?nsted-Lowrybase.16.3TheAutoionizationofwaterspontaneouslyformslowconcentrationsofwatermoleculetoanother.16.6Weakanacidtransfersaprotontosolventwater.16.7Weakamine（胺）Acompoundthathasthegeneralformulaandforming cationoranionreactswithwateritchangesthepH.bondedtoacentralatom.–COOHfunctionalgroup.AdditionalAspectsofAqueousTheCommon-Ionequilibriuminducedbyanioncommontothethesolubilityoftheslightlysolublesalt,or.smallamountofacidorbase..conjugatebaseinanaqueoussolution:pHpKlg changeappreciably.reactscompleywiththesolutepresentinthesolutehasjustreactedwithallthesolutepresentinofaddedtitrant.inachemicalequation.asolidsaltanditsionsinsolutionItprovidesatativemeasureofthesolubilityofaslightlysolublesalt.equilibriuminducedbyanioncommontothethesolubilityoftheslightlysolublesalt,or 17.7QualitativeysisforMetallicElements

tativeysis（定量分析）ThedeterminationEarth'sAtmospheretroposphere（對(duì)流層）TheregionofEarth'sdirectlyabovethetroposphere.photoionization（光致電離）TheremovalofanelectronfromanatomormoleculebyabsorptionOzoneintheUpperacidrain（酸雨）:Rainwaterthathas oxides,notablySO3,producedbyhumanactivities.mixtureofundesirablesubstancesproducedbytheolefinsandaldehydes.hemoglobin（血色素）Aniron-containingproteinresponsibleforoxygentransportintheblood.humanconsumption.bacteriaareabletooxidize.sourceofenergyAprocessmaybespontaneouseventhoughitisveryslow.canbereversedbyaninfinitesimalmodificationofavariablesuchastemperature.tothewayeventsoccurinnatureWhenaprocessoccursspontaneouslyinonedirectionitistostatethesecondlawinmanydifferentformsbutOneofthemostcommonstatementsfoundintheentropyoftheuniverseincreases.orspatialarrangementsinwhichasystemmaybefoundItisathermodynamicstatefunctionwhichmeansthatoncewespecifytheconditionsforasystem--thatisthetemperaturepressureandsoandnotbyhowitgottothatstateitsvalueisfixedwhentemperaturepressurecompositionandanentiremoleculemovesinadefinitedirection.atomswithinamoleculeinwhichtheymoveperiodicallytowardandawayfromoneanother.rotationalmotion（轉(zhuǎn)動(dòng)運(yùn)動(dòng)）Movementofamoleculeasthoughitisspinninglikeatop.absolutezerotemperatureiszeroS(0K0.

theformG=H–TS.Forachangeoccurringatenergyis G= H–TS.G=H–TS.funderstandardconditions.fcertainatomschange.chemicalreactions.reductionofsomeothersubstanceinanoxidation-reductionreaction.thatisreducedandtherebycausestheoxidationofsomeothersubstanceinanoxidation-reductionoxidationorareductionthatexplicitlyshowselectronsinvolved[forexample,Zn2+(aq)+2e-cellthepassageofelectronsthroughanexternalcircuit.cathode（陰極）Anelectrodeatwhichreduction(emf)1J/CAlsocalledelectromotiveforce.:

22.4Group7A:TheHalogensincludeIBrand22.7isoxidizedtoNO2HNO3isformedinadisproportionationreactionwhenNO2dissolvesin Thepotentialofareductionhalf-reactionunderalsocalledastandardelectrodepotential.electrodebasedonthehalf-reaction2(1M)+2totalchargeof1molofelectrons1F96,500C.20.8cathodicprotection（陰極保護(hù)）AmeansofcathodeinavoltaiccellThiscanbeachievedbyasananodetothemetaltobeprotected.20.9thepassageofcurrentunderasufficientexternalreactionsoccurarecalledelectrolyticcells.electrolyticcell（電解池）Adeviceinwhicha22.211H1nucleuscontainsaprotonandaneutron1:2H.

woodisheatedstronglyinadeficiencyofair.coalisheatedstronglyintheabsenceofair.andPb containsaprotonandtwoneutrons3H.1environmentconsistingofthesolidearth.whichoccursascalcite.mineral,usually othermaterialssuchassandandclay.ofchemicalandphysicalprocesses.Itisalsoc