Introductory Chemistry,2nd Edition Nivaldo Tro：化学导论第二版尼瓦尔多周转率

Btec,Biologydept,GuangdonginstituteofEducationChemistryforbiology

Chapter1MatterandEnergy2009,Bio-departmentArematter&energyrelatedMatterisanyparticlewithmassandvolumeEnergyissimplymatterthatismoving0KelvinisdefinedasthetemperaturewhenmatterdoesnotmovingSotemperatureisrelatedtomovingmassTherefore:temperatureandmassarerelatedtoenergyThat’swhyanychemistryorphysicsequationwithenergymustrelatemassandtemperature.23AroundyouEverythingyoucansee,touch,smellortasteinyourroomismadeofmatter.4WhatIsMatter?Matterisanythingwithmass.Typically,wethinkoftinylittlepiecesofmassasatomsandmoleculesbecausethose117elementsbehaveNewtonian.Thereareover200smallerparticlesthatbehaveQuantunian.5Energy:it’sjustMassandVelocityElectricalKineticenergyassociatedwiththeflowofelectricalcharge.HeatorThermalEnergyKineticenergyassociatedwithmolecularmotion.LightorRadiantEnergyKineticenergyassociatedwithenergytransitionsinanatom.NuclearPotentialenergyinthenucleusofatoms.ChemicalPotentialenergyintheattachmentofatomsorbecauseoftheirposition.6AtomsandMoleculesAtomsarethetinyparticlesthatmakeupallmatter.Inmostsubstances,theatomsarejoinedtogetherinunitscalledmolecules.Theatomsarejoinedinspecificgeometricarrangements.Anymattercanexistinoneof3StatesSolidLiquidGas78StructureDeterminesPropertiesTheatomsormoleculeshavedifferentstructuresinsolids,liquids,andgases−leadingtodifferentproperties.9SolidsTheparticlesinasolidarepackedclosetogetherandarefixedinposition.Althoughtheymayvibrate.Theclosepackingoftheparticlesresultsinsolidsbeingincompressible.Theinabilityoftheparticlestomovearoundresultsinsolidsretainingtheirshapeandvolumewhenplacedinanewcontainerandpreventstheparticlesfromflowing.10Solids,ContinuedSomesolidshavetheirparticlesarrangedinanorderlygeometricpattern—wecallthesecrystallinesolids.Saltanddiamonds.Othersolidshaveparticlesthatdonotshowaregulargeometricpatternoveralongrange—wecalltheseamorphoussolids.Plasticandglass.11LiquidsTheparticlesinaliquidarecloselypacked,buttheyhavesomeabilitytomovearound.Theclosepackingresultsinliquidsbeingincompressible.Theabilityoftheparticlestomoveallowsliquidstotaketheshapeoftheircontainerandtoflow.However,theydon’thaveenoughfreedomtoescapeandexpandtofillthecontainer.12GasesInthegasstate,theparticleshavecompletefreedomfromeachother.Theparticlesareconstantlyflyingaround,bumpingintoeachotherandthecontainer.Inthegasstate,thereisalotofemptyspacebetweentheparticles.Onaverage.13Gases,ContinuedBecausethereisalotofemptyspace,theparticlescanbesqueezedclosertogether.Therefore,gasesarecompressible.Becausetheparticlesarenotheldinclosecontactandaremovingfreely,gasesexpandtofillandtaketheshapeoftheircontainer,andwillflow.14Matter:isitpureorimpurePureSubstance=Allsamplesaremadeofthesamepiecesinthesamepercentages.SaltMixtures

=Differentsamplesmayhavethesamepiecesindifferentpercentages.SaltwaterPureSubstanceConstantCompositionHomogeneousMixtureVariableCompositionMatterHeterogeneousTro's"IntroductoryChemistry",Chapter315Mixtures1. Madeofmultiplesubstances,butappearstobeonesubstance.2. Allportionsofasamplehavethesamecompositionandproperties.1. Madeofmultiplesubstances,whosepresencecanbeseen.2. Portionsofasamplehavedifferentcompositionandproperties.HeterogeneousHomogeneous16MatterSummary17MatterhasPropertiesPhysicalPropertiesarethecharacteristicsofmatterthatcanbechangedwithoutchangingitscomposition.Characteristicsthataredirectlyobservable.ChemicalPropertiesarethecharacteristicsthatdeterminehowthecompositionofmatterchangesasaresultofcontactwithothermatterortheinfluenceofenergy.Characteristicsthatdescribethebehaviorofmatter.ChapterOne18H2OPhysicalversesH2OChemicalTro's"IntroductoryChemistry",Chapter319PhysicalPropertiesMeltingPointBoilingPointElectricalConductivityThermalConductivityMagnetismMalleabilityDuctilitySpecificHeatColorOrderTasteSolidLiquidGas20SomePhysicalPropertiesofIronIronisasilverysolidatroomtemperaturewithametallictasteandsmoothtexture.Ironmeltsat1538°Candboilsat4428°C.Iron’sdensityis7.87g/cm3.Ironcanbemagnetized.Ironconductselectricity,butnotaswellasmostothercommonmetals.Iron’sductilityandthermalconductivityareaboutaverageforametal.Itrequires0.45Jofheatenergytoraisethetemperatureofonegramofironby1°C.Tro's"IntroductoryChemistry",Chapter321ChemicalPropertiesAcidityBasicityInertnessExplosivenessInflammableFlammableOxidizingReducing22SomeChemicalPropertiesofIronIroniseasilyoxidizedinmoistairtoformrust.Whenironisaddedtohydrochloricacid(盐酸),itproducesasolutionofferricchlorideandhydrogengas.Ironismorereactivethansilver,butlessreactivethanmagnesium.Quiz:isitaPhysicalorChemicalPropertySaltisawhite,granularsolid=physical.Saltmeltsat801°C=physical.Saltisstableatroomtemperature,itdoesnotdecompose=chemical.36gofsaltwilldissolvein100gofwater=physical.Whenaclear,colorlesssolutionofsilvernitrateisaddedtoasaltsolution,awhitesolidforms=chemical.2324MatterhasProperties,MattercanalsogothroughChangesChangesthatalterthestateorappearanceofthematterwithoutalteringthecompositionarecalledphysicalchanges.Changesthatalterthecompositionofthematterarecalledchemicalchanges.Duringthechemicalchange,theatomsthatarepresentrearrangeintonewmolecules,butalloftheoriginalatomsarestillpresent.25IsitaPhysicalorChemicalChange?Aphysicalchangeresultsinadifferentformofthesamesubstance.Thekindsofmoleculesdon’tchange.Achemicalchangeresultsinoneormorecompletelynewsubstances.Alsocalledchemicalreactions.Thenewsubstanceshavedifferentmoleculesthantheoriginalsubstances.Youwillobservedifferentphysicalpropertiesbecausethenewsubstanceshavetheirownphysicalproperties.26PhaseChangesAre

PhysicalChangesBoiling=liquidtogas.Melting=solidtoliquid.Subliming=solidtogas.Freezing=liquidtosolid.Condensing=gastoliquid.Deposition=gastosolid.Statechangesrequireheatingorcoolingthesubstance.Evaporationisnotasimplephasechange,itisasolutionprocess.Evaporationofrubbingalcohol=physical.Sugarturningblackwhenheated=chemical.Aneggsplittingopenandspillingout=physical.Sugarfermentingintoalcohol=chemical.Bubblesescapingfromsoda=physical.

Bubblesthatformwhenhydrogenperoxide（过氧化氢）

ismixedwithblood=chemical.27Quiz:isitaPhysicalorChemicalchange28SeparationofMixturesSeparatemixturesbasedondifferentphysicalpropertiesofthecomponents.Physicalchange.Centrifugationanddecanting(离心和滗析)DensityEvaporation(蒸发)VolatilityChromatography(色谱)AdherencetoasurfaceFiltration(过滤)Stateofmatter(solid/liquid/gas)Distillation(蒸馏)BoilingpointTechniqueDifferentPhysicalProperty29Distillation:differentboilingpoints30Filtration:differentsolubility'sSummaryMovingMatterhasEnergy.Motionisrelatedtotemperature.AllenergyformulasarerelationsbetweenmassandtemperatureMatterhas3statesMatterhaspropertiesMattercanchange31States/Properties/Changeareallrelatedtotemperatureandhowmuchyouhave32LawofConservationofMassAntoineLavoisier“Matterisneithercreatednordestroyedinachemicalreaction.”Thetotalamountofmatterpresentbeforeachemicalreactionisalwaysthesameasthetotalamountafter.Butane(丁烷)+oxygencarbondioxide+water

58grams+208grams176grams+90grams 266grams=266grams33LawofConservationofEnergy“Energycanneitherbecreatednordestroyed.”

Thetotalamountofenergyintheuniverseisconstant.Thereisnoprocessthatcanincreaseordecreasethatamount.Note:neitherMassnorEnergyareeverdestroyed34EnergyTheFundamentalPrincipleoftheUniverseisEnergyFromtheGreekstoNewtontoQuantumMechanicsEnergyisknownasthecapacitytodoworkandissimplycalculatedbyknowingthemassandvelocityofaparticle.Theharderyouswinganaxthefasteryoucanfallatree.Guesswhathappenswhenyouwalkintoawall.005mphor500mph35Energy:it’sjustMassandVelocityElectricalKineticenergyassociatedwiththeflowofelectricalcharge.HeatorThermalEnergyKineticenergyassociatedwithmolecularmotion.LightorRadiantEnergyKineticenergyassociatedwithenergytransitionsinanatom.NuclearPotentialenergyinthenucleusofatoms.ChemicalPotentialenergyintheattachmentofatomsorbecauseoftheirposition.Youtakeslowmovingparticlesandmakethemmovefaster36TogetEnergy(electrical,thermal,light,nuclear,chemical)Asslowmovingwaterfalls,gravitypullsitfaster.Thewaterfallsontopofaturbine,whichmovesacoilinamagnettogenerateelectricity.Youtakeslowmovingparticlesandmakethemmovefaster37TogetEnergy(electrical,thermal,light,nuclear,chemical)Youtakeslowmovingparticlesandmakethemmovefaster38TogetEnergy(electrical,thermal,light,nuclear,chemical)Bindingenergyissimplytheamountofenergy(andmass)released,whenfreenucleonsjointoforma

nucleus;agluonisreleasedorabsorbedEinstein's

mass-energyequivalence

formula

E

=

mc²canbeusedtocomputethebindingenergy39KindsofEnergy

KineticandPotentialPotentialenergyisenergythatisstored;slowmovingWaterflowsbecausegravitypullsitdownstream.However,thedamwon’tallowittomove,soithastostorethatenergy.Kineticenergyisenergyofmotion,orenergythatisbeingtransferredfromoneobjecttoanother;fastmoving.Whenthewaterflowsoverthedam,someofitspotentialenergyisconvertedtokineticenergyofmotion.40MatterPossessesEnergyWhenapieceofmatterpossessesenergy,itcangivesomeorallofittoanotherobject.Allchemicalandphysicalchangesresultinthematterchangingenergy.Tro's"IntroductoryChemistry",Chapter341There’sNoSuchThingasaFreeRideWhenatomscontacteachother,frictionsisproduced.Youwilloftennoticefrictionassoundorheat.Soinsteadofusefulenergy,“anti-energy”frictionslowsyourcardown.42UnitsofEnergyCalorie(cal)istheamountofenergyneededtoraiseonegramofwaterby1°C.kcal=energyneededtoraise1000gofwater1°C.foodcalories=kcals.EnergyConversionFactors1calorie(cal)=4.184joules(J)1Kcalorie(Kcal)=1000calories(cal)1kilowatt-hour(kWh)=3.60x106joules(J)Tro's"IntroductoryChemistry",Chapter343EnergyUse2009UnitEnergyRequiredtoRaiseTemperatureof1gofWaterby1°CEnergyRequiredtoLight100-WBulbfor1HourEnergyUsedbyAverageU.S.Citizenin1Dayjoule(J)4.183.6x1059.0x108calorie(cal)1.008.60x1042.2x108Kcalorie(Kcal)1.00x10-386.02.2x105kWh1.1x10-60.1002.50x102Ex1.5,Acandybarhas225Kcal,converttoJoulesUnitsandmagnitudearecorrect.Check:Check.225Kcal=9.41x105JRound:Significantfiguresandround.Solution:FollowthesolutionmaptoSolvetheproblem.SolutionMap:WriteaSolutionMap.1Kcal=1000cal1cal=4.184JConversionFactors:WritedowntheappropriateConversionFactors.?JFind:WritedownthequantityyouwanttoFindandunit.225KcalGiven:WritedowntheGivenquantityanditsunit.CalcalJ3sigfigs3significantfigures45ChemicalPotentialEnergyTheamountofenergystoredinamaterialisitschemicalpotentialenergy.Thestoredenergyarisesmainlyfromtheattachmentsbetweenatomsinthemoleculestheattractiveforcesbetweenmolecules.46ExothermicProcessesWhenachangeresultsinthereleaseofenergyitiscalledanexothermicprocess.Anexothermicchemicalreactionoccurswhenthereactantshavemorechemicalpotentialenergythantheproducts.Theexcessenergyisreleasedintothesurroundingmaterials,addingenergytothem.Oftenthesurroundingmaterialsgethotterfromtheenergyreleasedbythereaction.47AnExothermicReactionPotentialenergyReactantsProductsSurroundingsreactionAmountofenergyreleased48EndothermicProcessesWhenachangerequirestheabsorptionofenergyitiscalledanendothermicprocess.Anendothermicchemicalreactionoccurswhentheproductshavemorechemicalpotentialenergythanthereactants.Therequiredenergyisabsorbedfromthesurroundingmaterials,takingenergyfromthem.Oftenthesurroundingmaterialsgetcolderduetotheenergybeingremovedbythereaction.49AnEndothermicReactionPotentialenergyProductsReactantsSurroundingsreactionAmountofenergyabsorbedTemperatureScalesCelsiusKelvinFahrenheit-273°C-269°C-183°C-38.9°C0°C100°C0K4K90K234.1K273K373K-459°F-452°F-297°F-38°F32°F212°FAbsolutezeroBPheliumBoilingpointoxygenBoilingpointmercuryMeltingpointiceBoilingpointwater0R7R162R421R459R671RRankineRoomtemp25°C298K75°F534R51Fahrenheitvs.CelsiusACelsiusdegreeis1.8timeslargerthanaFahrenheitdegree.Thestandardusedfor0°ontheFahrenheitscaleisalowertemperaturethanthestandardusedfor0°ontheCelsiusscale.52TheKelvinTemperatureScaleBoththeCelsiusandFahrenheitscaleshavenegativenumbers.Yet,realphysicalthingsarealwayspositiveamounts!TheKelvinscaleisanabsolutescale,meaningitmeasurestheactualtemperatureofanobject.0Kiscalledabsolutezero,allmolecularmotionstops.0K=-273°C=-459°F.Absolutezeroisatheoreticalvalueobtainedbyfollowingpatternsmathematically.53Kelvinvs.CelsiusThesizeofa“degree”ontheKelvinscaleisthesameasontheCelsiusscale.Althoughtechnically,wedon’tcallthedivisionsontheKelvinscaledegrees;wecallthemkelvins!Thatmakes1K1.8timeslargerthan1°F.The0standardontheKelvinscaleisamuchlowertemperaturethanontheCelsiusscale.Whenconvertingbetweenkelvinsand°C,rememberthatthekelvintemperatureisalwaysthelargernumberandalwayspositive!Example1.7—Convert–25°CtoKelvinsUnitsandmagnitudearecorrect.Check:Check.258KRound:Significantfiguresandround.Solution:FollowthesolutionmaptoSolvetheproblem.SolutionMap:WriteaSolutionMap.Equation:WritedowntheappropriateEquations.KFind:WritedownthequantityyouwanttoFindandunit.-25°CGiven:WritedowntheGivenquantityanditsunit.unitsplaceunitsplace°CKK=°C+273Example3.8—Convert55°FtoCelsiusUnitsandmagnitudearecorrect.Check:Check.12.778°C=13°CRound:Significantfiguresandround.Solution:FollowthesolutionmaptoSolvetheproblem.SolutionMap:WriteaSolutionMap.Equation:WritedowntheappropriateEquations.°CFind:WritedownthequantityyouwanttoFindandunit.55°FGiven:WritedowntheGivenquantityanditsunit.unitsplaceand2sigfigsunitsplaceand2sigfigs°F°CExample3.9—Convert310KtoFahrenheitUnitsandmagnitudearecorrect.Check:Check.98.6°F=99°FRound:Significantfiguresandround.Solution:FollowthesolutionmaptoSolvetheproblem.SolutionMap:WriteaSolutionMap.Equation:WritedowntheappropriateEquations.°FFind:WritedownthequantityyouwanttoFindandunit.310KGiven:WritedowntheGivenquantityanditsunit.unitsplaceand2sigfigsunitsplaceand2sigfigsK=°C+273°F°CK°C=K-27357Practice—Convert0°FintoKelvin58Practice—Convert0°FintoKelvin,Continued°C=0.556(°F-32)°C=0.556(0-32)°C=-18°CK=°C+273K=(-18)+273K=255K59HeatCapacityHeatcapacity(热容量)istheamountofheatasubstancemustabsorbtoraiseitstemperatureby1°C.cal/°CorJ/°C.Metalshavelowheatcapacities;insulators(绝缘/绝热)havehighheatcapacities.Specificheat(比热)

=heatcapacityof1gramofthesubstance.cal/g°CorJ/g°C.Water’sspecificheat=4.184J/g°Cforliquid.Or1.000cal/g°C.Itislessforiceandsteam.60SpecificHeat