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1、IntroductionChapter 1CopyrightTheMcGraw-HillCompanies,Inc.Permissionrequiredforreproductionordisplay.2021/6/71MatterAnythingthathasmassandtakesupspace.2021/6/72AtomsbuildingblocksofmatterAtoms are similar to LEGO pieces2021/6/73MatterAtomsarethebuildingblocksofmatter.Elementsarethesimplestformofmatt
2、erandcannotbebrokendownchemicallyintosimplersubstances.Eachelementismadeofthesamekindofatom.Acompoundismadeoftwoormoredifferentkindsofelementswithadefinitecomposition.2021/6/74TheStudyofChemistryMacroscopicMicroscopic2021/6/75ScientificMethod(Asystematicapproachtosolvingproblems)ObservationExperimen
3、tsTheoryYesNoLawExamplesofhypothesis:Ahypothesis isatentativeexplanationforasetofobservationsIfskincancerisrelatedtoultravioletlight,thenpeoplewithahighexposuretoUVlightwillhaveahigherfrequencyofskincancer.Ifleafcolorchangeisrelatedtotemperature,thenexposingplantstolowtemperatureswillresultinchanges
4、inleafcolor.Atheoryisaunifyingprinciplethatexplainsabodyoffactsand/orthoselawsthatarebasedonthem.Alawisaconcisestatementofarelationshipbetweenphenomenathatisalwaysthesameunderthesameconditions.AtomicTheoryForce=massxacceleration2021/6/78Matterisanythingthatoccupiesspaceandhasmass.Asubstanceisaformof
5、matterthathasadefinitecompositionanddistinctproperties.Chemistryisthestudyofmatterandthechangesitundergoesliquidnitrogengoldingotssiliconcrystals2021/6/79Amixtureisacombinationoftwoormoresubstancesinwhichthesubstancesretaintheirdistinctidentities.1.Homogenous mixturecompositionofthemixtureisthesamet
6、hroughout.2.Heterogeneous mixturecompositionisnotuniformthroughout.softdrink,milk,soldercement,ironfilingsinsand2021/6/710Physical meanscanbeusedtoseparateamixtureintoitspurecomponents.magnetdistillation2021/6/711Anelementisasubstancethatcannotbeseparatedintosimplersubstancesbychemical means.117elem
7、entshavebeenidentified82elementsoccurnaturallyonEarthgold,aluminum,lead,oxygen,carbon,sulfur35elementshavebeencreatedbyscientiststechnetium,americium,seaborgium2021/6/7122021/6/713A compoundisasubstancecomposedofatomsoftwoormoreelementschemicallyunitedinfixedproportions.Compoundscanonlybeseparatedin
8、totheirpurecomponents(elements)bychemicalmeans.lithiumfluoridequartzdryicecarbondioxide2021/6/714ClassificationofMatter2021/6/715AComparison:TheThreeStatesofMatter2021/6/716TheThreeStatesofMatter:EffectofaHotPokeronaBlockofIcesolidliquidgas2021/6/717Aphysical changedoesnotalterthecompositionoridenti
9、tyofasubstance.Achemical changealtersthecompositionoridentityofthesubstance(s)involved.icemeltingsugardissolvinginwaterhydrogenburnsinairtoformwaterTypesofChanges2021/6/718BoilingorEvaporationPhysicalChange2021/6/719ChemicalReaction2021/6/720RustingChemicalChange2021/6/721Anextensive property ofamat
10、erialdependsuponhowmuchmatterisisbeingconsidered.Anintensive property ofamaterialdoesnotdependuponhowmuchmatterisbeingconsidered.masslengthvolumedensitytemperaturecolorExtensiveandIntensiveProperties2021/6/722Matter-anythingthatoccupiesspaceandhasmass.massmeasureofthequantityofmatterSIunitofmassisth
11、ekilogram(kg)1kg=1000g=1x103gweightforcethatgravityexertsonanobject2021/6/723InternationalSystemofUnits(SI)2021/6/7242021/6/725MeasuringMass,Length,andVolumeThemeteristhestandardmeasureoflength,ordistance,intheSIandmetricsystems.Volumeistheamountofspaceoccupiedbyanobject.TheSIunitforvolumethecubicme
12、ter,m3issolargethattheliter(1L=0.001m3=1dm3)ismuchmorecommonlyused.2021/6/726Themetricsystemisbasedonfactorsof10andismucheasiertousethancommonU.S.units.2021/6/727DensitySIderivedunitfordensityiskg/m31g/cm3=1g/mL=1000kg/m3density=massvolumed=mVApieceofplatinummetalwithadensityof21.5g/cm3hasavolumeof4
13、.49cm3.Whatisitsmass?d=mVm=dxV =21.5g/cm3x4.49cm3=96.5g2021/6/7282021/6/729Whichisheavier,akilogramoffeathersorakilogramofbricks?Whichislarger?Iftwoobjectshavethesamemass,theonewiththehigherdensitywillbesmaller.2021/6/730K=C+273.15F=xC+3295273K=0C373K=100C320F=0C2120F=100CAComparisonofTemperatureSca
14、les2021/6/731Convert172.9FtodegreesCelsius.F=xC+3295F32=xC95x(F32)=C95C=x(F32)95C=x(172.932)=78.3952021/6/732Temperature,Heat,andEnergyThekelvinandtheCelsiusdegreearethesamesize.Thus,achangeintemperatureof1Cisequaltoachangeof1K.TheCelsiusscaleassignsavalueof0Ctothefreezingpointofwater.TheKelvinscale
15、assignsavalueof0Ktothecoldestpossibletemperature,absolute zero,whichisequalto273.15C.Thus,0K=273.15C,and+273.15K=0C.2021/6/733Temperature,Heat,andEnergyTemperatureconversions:K=C+273.15C=K273.152021/6/734ScientificNotationThenumberofatomsin12gofcarbon:602,200,000,000,000,000,000,0006.022x1023Themass
16、ofasinglecarbonatomingrams:0.00000000000000000000001991.99x10-23Nx10nNisanumberbetween1and10nisapositiveornegativeinteger2021/6/735ScientificNotation568.762n 0568.762=5.68762x102movedecimalleft0.00000772n 00.00000772=7.72x10-6movedecimalrightAdditionorSubtraction1.Writeeachquantitywiththesameexponen
17、tn2.CombineN1andN23.Theexponent,n,remainsthesame4.31x104+3.9x103=4.31x104+0.39x104=4.70x1042021/6/736ScientificNotationMultiplication1.MultiplyN1andN22.Addexponentsn1 andn2(4.0x10-5)x(7.0x103)=(4.0x7.0)x(10-5+3)=28x10-2=2.8x10-1Division1.DivideN1andN22.Subtractexponentsn1 andn28.5x1045.0x109=(8.55.0
18、)x1049=1.7x10-52021/6/737MeasurementandSignificantFiguresEveryexperimentalmeasurementhasadegreeofuncertainty.Thevolume,V,atrightiscertaininthe10splace,10mLV20mLThe1sdigitisalsocertain,17mLV18mLAbestguessisneededforthetenthsplace.2021/6/738Belowaretwomeasurementsofthemassofthesameobject.Thesamequanti
19、tyisbeingdescribedattwodifferentlevelsofprecisionorcertainty.2021/6/739SignificantFiguresAnydigitthatisnotzeroissignificant1.234kg4significantfiguresZerosbetweennonzerodigitsaresignificant606m3significantfiguresZerostotheleftofthefirstnonzerodigitarenotsignificant0.08L1significantfigureIfanumberisgr
20、eaterthan1,thenallzerostotherightofthedecimalpointaresignificant2.0mg2significantfiguresIfanumberislessthan1,thenonlythezerosthatareattheendandinthemiddleofthenumberaresignificant0.00420g3significantfigures2021/6/740Howmanysignificantfiguresareineachofthefollowingmeasurements?24mL2significantfigures
21、3001g4significantfigures0.0320m33significantfigures6.4x104molecules2significantfigures560kgambiguous2021/6/741Onceyoudecidehowmanydigitstoretain,therulesforroundingoffnumbersarestraightforward:RULE 1. Ifthefirstdigityouremoveis4orless,dropitandallfollowingdigits.2.4271becomes2.4whenroundedofftotwosi
22、gnificantfiguresbecausethefirstdroppeddigit(a2)is4orless.RULE 2. Ifthefirstdigitremovedis5orgreater,roundupbyadding1tothelastdigitkept.4.5832is4.6whenroundedoffto2significantfiguressincethefirstdroppeddigit(an8)is5orgreater.Ifacalculationhasseveralsteps,itisbesttoroundoffattheend.2021/6/742Significa
23、ntFiguresAdditionorSubtractionTheanswercannothavemoredigitstotherightofthedecimalpointthananyoftheoriginalnumbers.89.3321.1+90.432roundoffto90.4onesignificantfigureafterdecimalpoint3.70-2.91330.7867twosignificantfiguresafterdecimalpointroundoffto0.792021/6/743SignificantFiguresMultiplicationorDivisi
24、onThenumberofsignificantfiguresintheresultissetbytheoriginalnumberthathasthesmallestnumberofsignificantfigures4.51x3.6666=16.536366 =16.53sigfigsroundto3sigfigs6.8112.04=0.06069262sigfigsroundto2sigfigs=0.0612021/6/744MeasurementandSignificantFiguresSomenumbersareexactandeffectivelyhaveanunlimitednu
25、mberofsignificantfigures.Aclassmighthaveexactly32students(not31.9,32.0,or32.1).1footisdefinedtohaveexactly12inches.2021/6/745SignificantFiguresExactNumbersNumbersfromdefinitionsornumbersofobjectsareconsideredtohaveaninfinitenumberofsignificantfiguresTheaverageofthreemeasuredlengths:6.64,6.68and6.70?
26、6.64+6.68+6.703=6.67333=6.67Because3isanexact number=72021/6/746RoundingError5721(12.76012.20+1)=?RoundingateverystepRoundingonlyatthelaststep5721(1.560)=5721(2)5721(1.560)=8924.76=11442=9x103=1x1042021/6/747AccuracyhowcloseameasurementistothetruevaluePrecisionhowcloseasetofmeasurementsaretoeachothe
27、raccurate&preciseprecisebutnotaccuratenotaccurate¬precise2021/6/748DimensionalAnalysisMethodofSolvingProblems1.Determinewhichunitconversionfactor(s)areneeded2.Carryunitsthroughcalculation3.Ifallunitscancelexceptforthedesired unit(s),thentheproblemwassolvedcorrectly.givenquantityxconversionfactor=
28、desiredquantitygivenunitx=desiredunitdesiredunitgivenunit2021/6/749DimensionalAnalysisMethodofSolvingProblemsConversionUnit1L=1000mL1L1000mL1.63Lx=1630mL1L1000mL1.63Lx=0.001630L2mLHowmanymLarein1.63L?2021/6/750Thespeedofsoundinairisabout343m/s.Whatisthisspeedinmilesperhour?1mi=1609m1min=60s1hour=60min343msx1mi1609m60s1minx60min1hourx=767mihourmeterstomilessecondstohoursconversion units2021/6/751部分资料从网络收集整理而来，供大家参考，感谢您的关注！
