periodic table of the elements-元素周期律.ppt

PeriodicTableoftheelements,2015.12.21,WhatisthePeriodicTableofTheElements?,DmitriMendeleevwasthefirstscientisttocreateaperiodictableoftheelementssimilartotheoneweusetoday.YoucanseeMendeleevsoriginaltable(1869).Thistableshowedthatwhentheelementswereorderedbyincreasingatomicweight,apatternappearedwherepropertiesoftheelementsrepeatedperiodically.Thisperiodictableisachartthatgroupstheelementsaccordingtotheirsimilarproperties.,Thehistoryofthedevelopmentoftheperiodictableofelements,1.TheBeginningsofthePeriodicTableBeforewrittenhistory,peoplewereawareofsomeoftheelementsintheperiodictable.Elementssuchasgold(Au),silver(Ag),copper(Cu),lead(Pb),tin(Sn),andmercury(Hg).Itwasntuntil1649,however,untilthefirstelementwasdiscoveredthroughscientificinquirybyHennigBrand.Thatelementwasphosphorous(P).,By1869,63elementshadbeendiscovered.,Between1817-1829,JohannDobereinerbegantogroupelementswithsimilarpropertiesintogroupsofthreeortriads.,Thehistoryofthedevelopmentoftheperiodictableofelements,2.PrecursorstothePeriodicTableIn1862,A.E.BeguyerdeChancourtoiswasthefirstpersontomakeuseofatomicweightstorevealthattheelementswerearrangedaccordingtotheiratomicweightswithsimilarelementsoccurringatregularintervals.In1863,JohnNewlands,anEnglishchemist,proposedtheLawofOctaveswhichstatedthatelementsrepeatedtheirchemicalpropertieseveryeighthelement.,Thehistoryofthedevelopmentoftheperiodictableofelements,TheFathersofthePeriodicTableLotharMeyerandDmitriIvanovichMendeleevindependentlyproducedremarkablysimilarversionsoftheperiodictableofelementsattheessentiallythesametime.MendeleevperiodictableappearedinhisworkOntheRelationshipofthePropertiesoftheElementstotheirAtomicWeightsin1869.,Thethinkingofgiant,whenelementsarelistedaccordingtotheatomicmass,somepropertiesoccurperiodicallyActualversion:listedaccordingtotheatomicnumberIntuition:someelementwerestilltobediscovered!,Thethinkingofgiant,Valence:olddefinition,replacedbyotherslikeoxidationnumberHere:thenumberofHatomslinkedtotheelement:H=1(H2);He=0;Li=1(LiH);Be=2(BeH2);B=3(BH3);C=4(CH4);N=3(NH3);O=2(H2O);F=1(HF),etc.,Thehistoryofthedevelopmentoftheperiodictableofelements,3.TheModernPeriodicTableGlennSeaborgdiscoveredthetransuraniumelements,atomicnumbers94to102.Dr.Seaborgandhiscolleaguesarealsoresponsiblefortheidentificationofmorethan100isotopesofelements.,Thehistoryofthedevelopmentoftheperiodictableofelements,Listtheelementshorizontally,gotoanewlinewhenanoble(rare)gasisfound,placeelementswithsimilarbehaviourincolumns!,Thehistoryofthedevelopmentoftheperiodictableofelements,BlockshavedimensionLL=2,6,10,14=2x(2l+1)l=0,1,2,3Why?QuantumMechanicsexplainthisfundamentalfindingThefactor2arisesfromtwopossibleorientationsoftheelectronspin(duplicity)Theterm2l+1arisesfromthemultiplicityoftheangularquantumnumberl,goingfromlto+l(Magneticquantumnumber),thebasictrendsofthePeriodicTable,atomicradiusoftheisolatedatommetallic/non-metalliccharacteroftheelementtendencytogivemoleculesintheelementalstateelectronaffinityoftheisolatedatomionizationpotentialoftheisolatedatomelectronegativity(definedforanatominabond:seebelow)chemicalreactivityoftheelement,WhatisontheElementKey?,Eachsquareontheperiodictablegivesinformationaboutanelement.Onmanyprintedperiodictablesyoucanfindanelementssymbol,atomicnumber,andatomicweight.,PeriodsandGroups,Elementsintheperiodictablearrangedinperiods(rows)andgroups(columns).Atomicnumberincreasesasyoumoveacrossaroworperiod.,Rowsofelementsarecalledperiods.Theperiodnumberofanelementsignifiesthehighestunexcitedenergylevelforanelectroninthatelement.Thenumberofelementsinaperiodincreasesasyoumovedowntheperiodictablebecausetherearemoresublevelsperlevelastheenergyleveloftheatomincreases.,Periods,Groups,Columnsofelementshelpdefineelementgroups.Elementswithinagroupshareseveralcommonproperties.Groupsareelementshavethesameouterelectronarrangement.Theouterelectronsarecalledvalenceelectrons.Becausetheyhavethesamenumberofvalenceelectrons,elementsinagroupsharesimilarchemicalproperties.TheRomannumeralslistedaboveeachgrouparetheusualnumberofvalenceelectrons.Forexample,agroupVAelementwillhave5valenceelectrons.,Theatomicradiusisdefinedfortheisolatedatom(notalwayseasytoisolate!),describesthesizeofthesphericalelectroniccloudaroundthenucleusdependsonZ,Alsodefinedforions(ionicradii)Decreaseforlossofelectrons,increaseforgain,Firstionizationenergy(I.E.)istheenergyrequiredtoextractoneelectronfromtheisolatedatom.Successiveionizationenergiesarealsopossible.MeasuresthetendencyofanisolatedatomtolooseelectronsI.E.decreaseswithincreasingZ,Variationofthefirstionizationenergyalonggroupsandperiodsoftheperiodictable,ElectronaffinityAistheenergyreleasedwhenanisolatedatomcapturesoneelectron(someasuringthetendencytheisolatedatomhastoattractelectrons),Variationoftheelectronicaffinityalongthegroupsandperiodsoftheperiodictable,Electronegativity:propertyofanatominamoleculetoattractelectronsofanotheratomitbindstoAtypicalatomicproperty!Isameasurepossible?Mullikendefinition:theaveragebetweenfirstI.P.andElectronAffinity.Compromisebetweentendencytodonateandtendencytoacquireelectrons!Paulingdefinition:consideringtwoatomsXandY,thedifferenceinbondenergybetweenX-YandtheaverageofX-XandY-Ygivesanotherestimateofelectronegativity.ThetwoscalesmostlyCOINCIDE!Remarkablefact!ENcanbeconsideredasameasurablequantity,ofthepotentialtype(onereferencevaluemustbefixed).,Electronegativityandperiodictable,RegulartrendofENalongthetable:-mostelectronegative:F(fluorine)-nextmost:O,N,Cl-leastelectronegative:Cs,Rb,ConsideradiatomicmoleculeX-Y:bondelectronswillbedisplacedtowardsthemoreelectronegativeatom.IfthedifferenceinENislarge(say2),themoleculeisverypolarandbecomesunstable(ionicinfinitestructuresarepreferred!):solidNaFisconstitutedbyNa+cationsandF-anions.,Electronegativityisfundamentaltodefineoxidationnumbers!Entirelyionicstructuresarehelpfulfordeterminingoxidationnumbers,veryusefulinbalancingequationsandindicativeofredoxprocesses,Oxidationnumberisthecharge(realorapparent)giventoanatominatotallyionicstructureSimpleionshaveONequaltothechargetheycarry:e.g.Cl-,Ca2+Incompounds,ONisthechargeeachelementwouldassumeifelectronswereonthemoreelectronegativeatominabond.,Arrowindicatesthemoreelectronegativeatom,RulesforON,1.ElementshaveON=02.Fluorine,themostelectronegativeelementshasalwaysON=-1(ifnotelement)3.InmostcompoundsOxygen(thesecondmostelectronegativeelement)hasON=-2.Exceptions:i)peroxides,whereOxygenhasON=-1;ii)OF2,whereOxygenhasON+2.4.Inmostcompounds,HydrogenhasON=+1.Exception:metalhydrideswhereHydrogenhasON=-15.Incompounds,alkalimetalshavealwaysON=+16.Incompounds,alkali-earthmetals(metallialcalino-terrosi)havealwaysON=+27.ThealgebraicsumofONs:i)inanionisequaltothetotalchargeoftheion;ii)inamoleculeiszero.,Fundamentalcompoundsininorganicchemistry,PeriodicTable,Hhydrogen,Lilithium,Nasodium,Kpotassium,Rbrubidium,Cscaesium,Frfrancium,Beberyllium,Mgmagnesium,Cacalcium,Srstrontium,Babarium,Raradium,Scscandium,Yyttrium,Tititanium,Zrzirconium,Hfhafnium,Vvanadium,Nbniobium,Crchromium,Momolybdenum,Mnmanganese,Tctechnetium,Feiron,Ruruthenium,Cocobalt,Rhrhodium,Ninickel,Pdpalladium,Cucopper,Agsilver,Znzinc,Cdcadminium,Tatantalum,Wtungsten,Rerhenium,Ososminium,Iriridium,Ptplatinum,Augold,Hgmercury,Bboron,Sisilicon,Gegeramanium,Asarsenic,Sbantimoney,Tetellurium,Popolonium,Ccarbon,Pphosphorous,Nnitrogen,Ooxygen,Ssulphur,Seselenium,Alaluminium,Gagalium,Inindium,Tlthallium,Sntin,Pblead,Bibismuth,Ffluorine,Clchlorine,Brbromine,Iiodine,Atastatine,Hehelium,Neneon,Arargon,Krkrypton,Xexenon,Rnradon,LanthanideSeries(rareearth),ActiniumSeries,1,2,3,11,19,37,55,LaLanthanum,Cecerium,Prpraseodymium,Pmpromethium,Smsamarium,Eueuropium,Gdgadolinium,Tbterbium,Dydysprosium,Hoholmium,Reerbium,Tmthulium,Ybytterbium,Lulutetium,Ndneodymium,Acactinium,Paprotactinium,Uuranium,Npneptunium,Puplutonium,Amamericium,Cmcurium,Bkberkelium,Cfcalifornium,Eseinsteinium,Fmfermium,Mdmendelevium,Ththorium,Nonobelium,Lrlawrencium,87,4,12,20,38,56,88,39,22,21,40,72,23,41,73,24,42,74,25,43,74,26,44,76,27,45,77,28,46,78,29,47,79,30,48,80,31,49,81,5,13,32,50,82,6,14,33,51,83,7,15,34,52,84,8,16,35,53,85,9,17,36,54,86,10,18,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,Representativevs.TransitionElements,Therearetwosetsofgroups.ThegroupAelementsarecalledtherepresentativeelements.ThegroupBelementsarethenonrepresentativeelements.,ClassifyingElements,Nonmetals,Thenonmetalsarepoorconductorsofheatandelectricity.Solidnonmetalsarebrittleandlackmetallicluster.Mostnonmetalsgainelectronseasily.Thenonmetalsarelocatedontheupperrightsideoftheperiodictable,separatedfrommetalsbyalinethatcutsdiagonallythroughtheperiodictable.Thenonmetalscanbedividedintoclassesofelementsthathavesimilarproperties.Thehalogensandthenoblegasesaretwogroupsofnonmetals.,Metalloids,Mostelem