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梓桢国际内部教学资料报班电话15001212231www.
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(HCO3-盐一定可溶)常见强酸:HCl、H2SO4、HNO3、H3PO4.
(强酸和中强酸)常见强碱:NaOH、KOH、Ba(OH)2、Ca(OH)2.
(强碱和中强碱)Chapter1MolesandEquationsContentIRelativemassesofatomsandmoleculesIIThemole,theAvogadroconstantIIIThedeterminationofrelativeatomicmasses,Ar,andrelativemolecularmasses,Mr,frommassspectraIVThecalculationofempiricalandmolecularformulaeVReactingmassesandvolumes(ofsolutionsandgases)LearningoutcomesThetermrelativeformulamassorMrwillbeusedforioniccompoundsCandidatesshouldbeableto:(a)definethetermsrelativeatomic,isotopic,molecularandformulamasses,basedonthe12Cscale(b)definethetermmoleintermsoftheAvogadroconstant(c)*analysemassspectraintermsofisotopicabundancesandmolecularfragments[knowledgeoftheworkingofthemassspectrometerisnotrequired](d)calculatetherelativeatomicmassofanelementgiventherelativeabundancesofitsisotopes,oritsmassspectrum(e)definethetermsempiricalandmolecularformulae(f)calculateempiricalandmolecularformulae,usingcombustiondataorcompositionbymass(g)*writeand/orconstructbalancedequations(h)performcalculations,includinguseofthemoleconcept,involving:(i)reactingmasses(fromformulaeandequations)(ii)volumesofgases(e.
g.
intheburningofhydrocarbons)(iii)volumesandconcentrationsofsolutionsWhenperformingcalculations,candidates'answersshouldreflectthenumberofsignificantfiguresgivenoraskedforinthequestion.
Whenroundingupordown,candidatesshouldensurethatsignificant梓桢国际内部教学资料报班电话15001212231www.
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1definitions1)relativeatomicmass,Ar,ofanelementistheweightedaveragemassofanatomoftheelementrelativetothemassofanatomofcarbon-12,whichhasamassofexactly12.
是比值无单位unit2)relativeformulamasstheweightedaveragemassoftheformulaofacompoundrelativetoanatomofcarbon-12,whichhasamassofexactly12.
3)relativemolecularmasstheweightedaveragemassofamoleculeofacompoundrelativetoanatomofcarbon-12,whichhasamassofexactly12.
=4)relativeisotopicmassthemassofanisotopeofanatomofanelementrelativetoanatomofcarbon-12,whichhasamassofexactly12.
1.
2FindingrelativeAtomicmass1.
3DeterminationofArfrommassspectra从质谱仪中测Ar(1)Abundanceandpeaks梓桢国际内部教学资料报班电话15001212231www.
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B:Abeamofthesepositiveionsisacceleratedbyusingapositivelychargedelectrodetorepelit.
C:Thebeamofpositiveionspassesthroughamagneticfieldwhereionsaredeflectedaccordingtotheirmasses.
D:thelighterionsdefleetmoreE.
Adetectormeasurestherelativeabundanceofeachisotopepresent.
1.
4Countingchemicalsubstancesinbulk----ThemoleandAvogadro'sconstant(1)definition:onemoleofasubstanceistheamountofthatsubstancewhichhasthesamenumberofspecificparticlesasthereareatomsinexactly12gofthecarbon-12isotope.
≈6*10231万→104个1million→106个1mol→6*1023个molarmass:Weoftenrefertothemassofamoleofsubstanceasitsmolarmass(abbreviationM).
Theunitsofmolarmassareg.
mol-1.
(2)常见基本公式及基本计算n=n物质的量amountofsubstance(mole)m:物质的实际质量(g)M:摩尔质量molarmass(g.
mol-1)n=(N:粒子个数L:Avogadro'sconstant6*1023)(适合于固、液、气态)Volumeof1molgas≈24dm3n==(室温,室压下,只适合于气体)GasVolume(气体体积):V(dm3),atroomtemperature,andpressure(3)Concentrationofsolution(溶液浓度)梓桢国际内部教学资料报班电话15001212231www.
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dm-3)=(n的单位为molv的单位为dm-3)mol.
dm-3→M3mol.
dm-3→3M(4)Chemicalequations化学方程式含义C(s)+O2(g)=CO2(g)ratioofamountofsubstance1:1:1massofreactant12:32:442H2(g)+O2(g)=2H2O(l)物质量比2:1:2(2*21*3218*2)质量比4:32:361.
5Writingchemicalformula(书写化学式)(1)常见的元素及其化合价→oxidationstateH+,Li+Na+K+Mg2+,Ca2+→GroupIIAl3+F-1Cl-Br-1I-,NO3-O2-,S2-,CO32-,SO42-,SO32-PO43-(2)书写writing→物质内所有元素和为零+5-2P2O5命名规则:①metalsdonotusuallychangetheirnames,(金属通常在化合物中不变名称)②non-metalschangetheirnamebybecoming–ide(非金属通常在后面加-ide后缀)③非金属与非金属的化合物egCO2,NO2,SO3,SO2④底标数字1-mono2-di3-tri4-tetra5-penta6-hexa7-hepta8-octa(3)命名总结:①:金属+非金属(离子化合物),非金属+非金属(其他化合物)Xm化合物为正的元素名称不变Yn化合物为负的后缀-ideegCO2→CarbondioxideNaCl→Sodiumchloride梓桢国际内部教学资料报班电话15001212231www.
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FeOFe3O4Fe2O3FeO:iron(II)oxideFe2O3:iron(III)oxideFe3O4:tri-inntetraoxide碱:OH-hydroxideeg:NaOHsodiumhydroxide变价:Fe(OH)3iron(III)hydroxideFe(OH)2亚铁iron(II)hydroxide或ferroushydroxide酸:acidH2SO4硫酸sulphuricacidH3PO4磷酸phosphoricacidHCl盐酸(非含氧酸)hydrochloricacidHNO3硝酸NitricacidH2S氢硫酸hydrosulpharicacid1.
6WritingandBalancingchemicalequation梓桢国际内部教学资料报班电话15001212231www.
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2Na++2OH-+2H++SO42-→2Na++SO42-+2H2O2OH-+2H+→2H2O→离子反应式反应了化学变化中真正参加反应的物OH-+H+→H2O(l)总结:能拆的物质(强电解质)强酸:H2SO4HClHNO3HBrHI强碱:NaOHKOHCa(OH)2Ba(OH)2可溶性盐(溶解度口诀)钾钠铵硝酸溶,硫酸去铅钡,盐酸去银汞,其他都不溶(HCO3-的盐都溶)1.
7Combustionanalysis氧化燃烧的分析法一般适合于含CHO等有机物eg:0.
500gofanorganiccompoundX(含CHO)produces0.
733gofCO2and0.
300gofH2Ooncompletecombustion,又知Mris60.
1.
CxHyOz+O2→XCO2+H2O1Xn==x=2=y=4梓桢国际内部教学资料报班电话15001212231www.
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Chapter2AtomicStructureContentThenucleusoftheatom:neutronsandprotons,isotopes,protonandnucleonnumbersLearningoutcomesCandidatesshouldbeableto:(a)*identifyanddescribeprotons,neutronsandelectronsintermsoftheirrelativechargesandrelativemasses(b)*deducethebehaviourofbeamsofprotons,neutronsandelectronsinelectricfields(c)describethedistributionofmassandchargeswithinanatom(d)deducethenumbersofprotons,neutronsandelectronspresentinbothatomsandionsgivenprotonandnucleonnumbers(andcharge)(e)(i)describethecontributionofprotonsandneutronstoatomicnucleiintermsofprotonnumberandnucleonnumber(ii)distinguishbetweenisotopesonthebasisofdifferentnumbersofneutronspresent梓桢国际内部教学资料报班电话15001212231www.
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Thenucleusismadeupofparticlescallednucleons.
Therearetwotypesofnucleon:protonsandneutrons.
Atomsofdifferentelementshavedifferentnumbersofprotons.
Outsidethenucleus,particlescalledelectronsmovearoundinregionsofspacecalledorbitals.
Chemistsoftenfinditconvenienttouseamodeloftheatominwhichelectronsmovearoundthenucleusinelectronshells.
Eachshellisacertaindistancefromthenucleusatitsownparticularenergylevel.
Inaneutralatom,thenumberofelectronsisequaltothenumberofprotons.
AsimplemodelofacarbonatomisshowninFigure2.
3.
Thismodelisnotveryaccuratebutitisusefulforunderstandingwhathappenstotheelectronsduringchemicalreactions.
梓桢国际内部教学资料报班电话15001212231www.
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3Amodelofacarbonatom.
2、Massesandchargesofelectrons,protonsandneutrons质子\中子\电子的相对电荷与质量carriesachargeof+1.
6*10-19Cprotonrelativemassis1withoutcharge,carries(has)nochargeneutronrelativemassis1carriesachargeof-1.
6*10-19Celectronmassoftheelectronis1/1836ofthatofneutron/proton,negligible.
Summary:Sub-atomicparticleSymbolRelativemassRelativechargeelectrone1/1836-1neutronn10protonp1+1Table2.
2Comparingelectrons,neutronsandprotons.
3、behaviorofprotons,electronsandneutronsinelectricfield.
Whenabeamofelectrons,neutronsandprotonswiththesamespeed,areincidentintoanelectricfield,wewillobservesuchbehavior:1.
directionofthedeviation:electronsdeviatetothepositivepole,protonsdeviatetothenegativepole,andneutronsdonotdeviate,becauseelectronscarrynegativecharge,neutronsnocharge,andprotonspositivecharge.
2.
extentofthedeviation:electronsdeviatemorethanprotonsbecauseitsmassisfarsmaller(1/1836)thanthatofproton.
梓桢国际内部教学资料报班电话15001212231www.
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Almostthetotalmassofanatomrestsonthenucleus,becausemassofelectronsisverysmallrelativetothatofprotonandneutron.
Inanatom,therearesamenumberofprotonsandelectrons,andprotonandelectroncarrythesameamountofbutoppositecharge,sotheatomisneutral.
Foranatom:numberofelectron=numberofproton=AtomicnumberNucleonnumber(massnumber)=protonnumber+neutronnumber(B:nucleonnumber,A:protonnumber/atomicnumber)neutronnumber=B–Aeg、5、isotopes同位素Definition:Atomswhichhavethesamenumberofprotonsbutdifferentnumberofneutrons.
Becauseelectronsholdthekeytoalmostthewholeofchemistry,soisotopeshavethesamechemistry(chemicalproperties)因为电子几乎决定了原子的所有化学性质,所以同位素的化学性质相同.
Homework:ALLtheWorkedExamples,End-of-chapterquestionsandCheck-up!
Chapter3ElectronsinAtomsContentElectrons:electronicenergylevels,ionisationenergies,atomicorbitals,extranuclearstructureLearningoutcomesCandidatesshouldbeableto:(f)*describethenumberandrelativeenergiesofthes,panddorbitalsfortheprincipalquantumnumbers1,2and3andalsothe4sand4porbitals.
梓桢国际内部教学资料报班电话15001212231www.
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1SimpleelectronicstructureThearrangementofelectronsinanatomiscalleditselectronicstructureorelectronicconfiguration.
SomeelectronicconfigurationsareshowninFigure3.
2Figure3.
2Thesimpleelectronicstructuresoflithium,neonandchlorine.
Thenudeioftheatomsarenotshown.
3.
2Evidenceforelectronicstructure:ionisationenergyionisationenergy电离能(1)Definition:thefirstionisationenergyofanelementistheamountofenergyneededtoremoveoneelectronfromeachatominamoleofatomsofanelementinthe梓桢国际内部教学资料报班电话15001212231www.
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(2)SymbolHi1Hi2Hi3.
.
.
.
.
.
.
.
.
.
.
.
(3)Equationofionisationenergy:eg.
ForCa:Hi1Hi2Hi3(4)factorsaffectingionisationenergy(影响电离能的因素)因素(i):Thesizeofthenuclearcharge核电荷的大小Asthepositivenuclearchargeincreases.
theattractiveforcebetweenthenucleusandtheelectronsincreases.
So,moreenergyisneededtoovercometheseattractiveforcestoremovedtheelectron.
Thenuclearchargeincreases,ionisationenergyincrease因素(ii):DistanceofouterelectronsfromthenucleusAsthedistancebetweenthemincreases,theattractionbetweentheelectronsandnucleusdecreases,sotheionisationenergydecreasestoo.
因素(iii):ShieldingeffectofinnerelectronsAboutShieldingeffect:Sinceallelectronsarenegativelycharged,theyrepeleachother.
Electronsininnershellsrepelelectronsinoutershells.
Fullinnershellsofelectronspreventthefullnuclearchargebeingfeltbytheouterelectrons.
Thisiscalledshielding.
Sinceelectronsareallnegativelycharged,Electronsininnershellsrepelelectronsinoutershells,asthenumberofelectronsininnershellsincreases,theshieldingincreases,theionisationenergydecreases.
Hits:比较不同的粒子(原子,离子)半径的方法:先看电子层(shells)数目,电层数↑半径↑,当电子层相同,看质子数,质子数↑半径↓.
(5)Successiveionisationenergy连续电离能Wecancontinuetoremoveelectronsfromanatomuntilonlythenucleusisleft.
Wecallthissequenceofionisationenergies,successiveionisationenergies.
ThedatainTable3.
2showsusthat:1H13102He237052503Li5197300118004Be900176014850210005B7992420366025000328006C1090235046201622037800473007N140028604580748094505330064400801310339053207450110001330071300841009F16803370604084101100015200179009200010600010Ne208039506150929012200152002000023000117000131400梓桢国际内部教学资料报班电话15001212231www.
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2Successiveionisationenergiesforthefirst11elementsinthePeriodicTable.
features特征:(a)Foreachelement,thesuccessiveionisationenergiesincreasewhenremovingelectronsfromthesameshell.
.
Thisisbecausethechargeontheiongetsgreateraseachelectronisremoved.
Aseachelectronisremovedthereisagreaterattractiveforcebetweenthepositivelychargedprotonsinthenucleusandtheremainingnegativelychargedelectrons.
Thereforemoreenergyisneededtoovercometheseattractiveforces.
(b)Thereisabigdifferencebetweensomesuccessiveionisationenergies.
Fornitrogenthisoccursbetweenthe5thand6thionisationenergies.
Forsodiumthefirstbigdifferenceoccursbetweenthe1stand2ndionisationenergies.
Theselargechangesindicatethatforthesecondofthesetwoionisationenergiestheelectronbeingremovedisfromaprincipalquantumshellclosertothenucleus.
(6)ApplicationforsuccessiveionisationenergyInterpretingsuccessiveionisationenergiesTakeAlforexample:Thesketchgraphshowsthe13successiveionisationenergiesofaluminium.
Numberofelectronsremoved3.
3Sub-shellsandatomicorbitals(1)Quantumsub-shellsn=1n=2n=3Theprincipalquantumshells,apartfromthefirst,aresplitintosub-shells(sub-levels).
Eachprincipalquantumshellcontainsadifferentnumberofsub-shells.
Thesubshellsaredistinguishedbytheletterss,pord.
Therearealsofsub-shellsforelementswithmorethan57electrons.
Figure3.
6showsthesub-shellsforthefirstfourprincipalquantumlevels.
Inanyprincipalquantumshell,theenergyoftheelectronsinthesub-shellsincreasesintheorders﹤p﹤d梓桢国际内部教学资料报班电话15001212231www.
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Summary:typesofsub-shells:n=1,s;n=2,s,p;n=3,s,p,d;n=4,s,p,d,f;(2)AtomicorbitalsEachsub-shellcontainsoneormoreatomicorbitals.
eachorbitalcanonlyholdamaximumoftwoelectrons.
(3)ShapesoftheorbitalsEachorbitalhasathree-dimensionalshape.
Withinthisshapethereisahighprobabilityoffindingtheelectronorelectronsintheorbital.
Figure3.
7showshowwerepresenttheirshapes.
(i)sorbitals:1sbeaware:2sorbitalislargerthan1s,butthesameshape(ii)porbitals(4)FillingtheshellsandorbitalsThemoststableelectronicconfiguration(electronicstructure)ofanatomistheonethathasthelowestamountofenergy.
Theorderinwhichthesub-shellsarefilleddependsontheirrelativeenergy,theorderofenergylevelsofthesub-shellsareshownbelow,inincreasingorder:1s2s2p3s3p4s3d4p4d4f(5)pauliexclusionprincipleandspin-paired同一轨道电子必须oppositespin,最稳定的electronconfiguration是两种:全充满(反旋)半充满梓桢国际内部教学资料报班电话15001212231www.
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4AmorecomplexmodelforelectronicconfigurationsRepresentingelectronicconfigurationsElementnumberSymbolElectronicconfiguration1HIs12HeIs23LiIs22s14BeIs22s25Bls22s22p'6Cls22s22p27Nls22s22p380ls22s22p49Fls22s22p510Nels22s22p611Nals22s22p63s!
Table3.
5Electronicconfigurationsforthefirst18elementsinthePeriodicTable.
ChromiumandcopperTheelectronicconfigurationsofchromiumandcopperdonotfollowtheexpectedpattern.
Chromiumhastheelectronicconfiguration[Ar]3d54s1(ratherthantheexpected[Ar]3d44s2).
Copperhastheelectronicconfiguration[Ar]3d104s1(ratherthantheexpected[Ar]3d94s2).
OrbitalsandthePeriodicTableThearrangementofelementsinthePeriodicTablereflecttheelectronicstructureoftheelements.
ThePeriodicTablecanbesplitintoblocksofelements(Figure3.
10).
ElementnumberName(Symbol)Electronicconfiguration19Potassium(K)[Ar]4s120Calcium(Ca)[Ar]4s221Scandium(Sc)[Ar]3d14s224Chromium(Cr)[Ar]3d54s'25Manganese(Mn)[Ar]3d54s229Copper(Cu)[Ar]3d104s'30Zinc(Zn)[Ar]3d104s231Gallium(Ga)[Ar]3d,04s24p135Bromine(Br)[Ar]3d'°4s24p536Krypton(Kr)[Ar]3d104s24p6Table3.
6Electronicconfigurationsforsomeoftheelements19to36,where[Ar]istheelectronicstructureofargonls22's22p63s23p6.
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ElementsinGroupsIIIto0(apartfromHe)haveouterelectronsinapsub-shell.
Elementsthataddelectronstothedsub-shellsarecalledthed-blockelements.
Mostofthesearetransitionelements.
FillingtheorbitalsAusefi.
ilwayofrepresentingelectronicconfigurationsisadiagramwhichplaceselectronsinboxes(Figure3.
11).
Eachboxrepresentsanatomicorbital.
Theboxes(orbitals)canbearrangedinorderofincreasingenergyfrombottomtotop.
Anelectronisrepresentedbyanarrow.
Thedirectionofthearrowrepresentsthe'spinoftheelectron.
(WeimagineanelectronrotatingarounditsownaxiseitherinaclockwiseoranticlockwiseElectronicconfigurationofions:easy!
!
3.
5PatternsinionisationenergiesinthePeriodicTablePatternsacrossaperiodFigure3.
13showshowthefirstionisationenergy,Achangesacrossthefirsttwoperiods.
Wecanexplaintheformofthegraphmainlybyreferringtothethreethingsthatinfluenceionisationenergies.
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ThisappliestoPeriod1(hydrogenandhelium),Period2(lithiumtoneon)andalsotootherperiods.
Asyougoacrossaperiodthenuclearchargeincreases.
Buttheelectronremovedcomesfromthesameshell.
So,theforceofattractionbetweenthepositivenucleusandtheouternegativeelectronsincreasesacrosstheperiodbecause:ithenuclearchargeincreasesiithedistancebetweenthenucleusandtheouterelectronremainsreasonablyconstantiiitheshieldingbyinnershellsremainsreasonablyconstant.
2)Thereisarapiddecreaseinionisationenergybetweenthelastelementinoneperiodandthefirstelementinthenextperiod.
ithedistancebetweenthenucleusandtheouterelectronincreasesiitheshieldingbyinnershellsincreasesiiithesetwofactorsoutweightheincreasednuclearcharge.
3)Althoughboronhasonemoreprotonthanberyllium,thereisaslightdecreaseinHi1onremovaloftheouterelection.
BerylliumhastheelectronicstructureIs22s2andboronhastheelectronicstructure1s22s22p1.
Theelectronremovedinboronisinthe2psub-shell,whichisslightlyfurtherawayfromthenucleusthanthe2ssub-shell.
Thereislessattractionbetweentheelectroninboronandthenucleusbecause:ithedistancebetweenthenucleusandtheouterelectronincreasesslightlyiitheshieldingbyinnershellsincreasesslightlyiiithesetwofactorsoutweightheincreasednuclearcharge.
4)ThereisaslightdecreaseinHi1nbetweennitrogenandoxygen.
Oxygenhasonemoreprotonthannitrogenandtheelectronremovedisinthesame2psubshell.
However,thespin-pairingoftheelectronsplaysaparthere.
IfyoulookbackatFigure3.
12,youwillseethattheelectronremovedfromthenitrogenisfromanorbitalwhichcontainsanunpairedelectron.
Theelectronremovedfromtheoxygenisfromtheorbitalwhichcontainsapairofelectrons.
Theextrarepulsionbetweenthepairofelectronsinthisorbitalresultsinlessenergybeingneededtoremoveanelectron.
SoHi1foroxygenislower,becauseofspin-pairrepulsion.
Note:Thesepatternsrepeatthemselvesacrossthethirdperiod.
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Forexample,inGroupIthevaluesofHi1are:Li=519kjmol-1Na=494kjmol-1K=418kjmol-1Rb=403kjmol-1Asyougodownthegroup,theouterelectronremovedisfromasuccessivelyhigherprincipalquantumlevel-2sfromlithium,3sforsodiumand4sforpotassium.
Althoughthenuclearchargeisincreasingdownthegroupthereislessattractionbetweentheouterelectronandthenucleusbecauseithedistancebetweenthenucleusandtheouterelectronincreasesiitheshieldingbycompleteinnershellsincreasesiiithesetwofactorsoutweightheincreasednuclearcharge.
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