氢、碱金属和碱土金属课件

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氢、碱金属和碱土金属Hydrogen,AlkaliandAlkali-earthmetals氢、碱金属和碱土金属Hydrogen,Alkali1氢及其化合物(Hydrogenantitscompounds)氢在周期表中排A,又能排A,这是由于第一周期的稀有气体电了构型为1s2。一、单质氢(Simplesubstanceofhydrogen)1、氢的同位素(isotope)(1)PP+nP+2nProtiumDeuteriumTritium氕氘氚1氢及其化合物(Hydrogenantitscomp(2)存在:H:D=6800:1(原子个数)H:T=1e10:1HeatCool(2)存在:H:D=6800:1(原子个数)H:T=(4)氢同位素形成的单质H2、D2、T2,在化学性质上完全相同,但物理性质(熔沸点)上有差别。2.Properties:(1)Physicalproperties:H2:极难溶于水和有机溶剂,可以贮存在金属(Pt、Pd)和合金(LaNi5)中固态氢(黑色)又称为金属氢:在晶格质点上为质子,而电子为整个晶体享,所以这样的晶体具有导电性,固态氢可能为立方或六方分子晶格。(4)氢同位素形成的单质H2、D2、T2,在化学性质上(2)Chemicalproperties:a.成键特点:电子构型为1s,可以放在A类,但第一电离势高于碱金属的第一电离势;也可放在A类。b.化合反应:与金属:2Na+H2=2NaHCa+H2=CaH2与非金属:H2+F2=2HFc.还原反应:CuO+H2=Cu+H2OWO3+3H2=W+3H2O(2)Chemicalproperties:3.Preparation(1)实验室:(2)工业上:二、氢化物(Hydride)放在以后各章元素中讲解http:/www.chemsys.t.u-tokyo.ac.jp/laboratory_domen-kubota_e.htmlSi(s)+Ca(OH)2(s)+2NaOH(s)=Na2SiO3(s)+CaO(?)+2H2(g)3.Preparation二、氢化物(Hydride)放在2碱金属元素及其化合物碱金属元素及其化合物AlkalimetalsandtheircompoundsLithiumSodiumPotassiumLiNaKRubidiumCesiumFranciumRbCsFr2碱金属元素及其化合物forstructuralandmechanisticstudiesofionchannelsRoderickMacKinnonTheNobelPrizeinChemistry2003PeterAgre,RoderickMacKinnonK+channelforstructuralandmechanistic氢、碱金属和碱土金属课件氢、碱金属和碱土金属课件氢、碱金属和碱土金属课件IwasbornonFebruary19,1956inthemiddleofasnowstorm.Itremainsoneofthosehumorousfamilystoriesthatmymotherlikestotell.Myfathertheplannerhadrehearsedthewaytothehospitalbutapparentlythingslookedalotdifferentatnightinablizzard.EventuallytheymadeitandsodidI,thefourthofsevenchildren.MyfatherwasapostalworkerwhenIwasveryyoungbutstudiedcomputersand became a programmer on the big IBM main frames.My mother worked as a part timeschoolteacher,butmostlytookcareofthechildrenathome.ThinkingbackonitnowIknowwedidnothavemuchmoneybutIneverknewthatgrowingup.Myparentsprovidedahappyenvironmentandmadetheirexpectationscleartous.Televisionisbadforyou,readingisgoodforyou,andyoubettergetanAforeffortinschool.Whatyouendupdoinginlifeisuptoyou.Justmakesureyouenjoywhatyoudobecause thenyouwilldoitwell.Weallpursued completely different walksoflife.Ibecame thescientist.Isupposethereweresomeearlyindicationsofmytendencytoalifeofcuriosity.ApparentlyfromaveryyoungageIhadahabitofaskinglotsofquestions:whatwouldhappenif.?wasafavorite.AndIlikedhavingfactsstraightandknowinghowthingsworkanddidnothesitatetogiveexplanationstothosearoundme,apparentlytoanannoyingdegreesometimes.Irememberonedaymyfather,attheendofhispatience,commentingthatIwasacompendiumofuselessinformation.Icertainlycanunderstandhisplightwithoneofthesevenhavingwaytoomanyquestionsandanswersallthetime.Onthepositiveside,IlearnedanewwordthatdaywhenIlookedupcompendiuminthedictionary.Therewereprobablyevenindicationsthatmycuriositymightbescientific.BurlingtonMassachusettswasruralwhenIwasyoungandIlovedtoroamandexplore.Ihadrockcollectionsandreadchildrensbooksongeologyandthehistoryoftheearth.Imadelittlevolcanoesoutofplasterofparisandaddedbakingsodaandvinegartothecraterstosimulatevolcaniceruptions.Ihadanaccidentonedaythatmademymotherlaughtomyutterfrustration:atthatyoungageIfailedtoappreciatethehumorinalittleboytellinghismotherhehaddroppedavolcanoonhistoe!InthesummerIcollectedbutterflies,turtles,snakesandotherlivingthings.OnesummermymotherenrolledmeinascienceenrichmentclassforelementaryschoolstudentsandIwasallowedtotakehomeamicroscope.IusedittolookateverythingIcouldfind:microorganismsfromthenearbypond,leavesandbladesofgrass.Ispenthourafterhouralone,mesmerizedbythetinylittlethingsthatIcouldsee.IwasbornonFebruary19,195Myscientificcuriositytookabackseattoathleticsthroughjuniorhighandhighschool.Gymnasticswasagoodmatchtomysmallbuildandtomysolitarynature.Iwasamemberofateambutgymnasticsisanindividualsport.Youlearnatechnique,thenamove,andthenaroutine.Andthenyouperfectitthroughpractice,workingmostlyalone.Ihadaverygoodnononsenseteacher,coachHayes,whoreallyinstilledinmetheideaofperfectionthroughpractice.Iwasactuallynotallthatbad,particularlyatfloorexerciseandhighbar.Ievenconsideredpursuinggymnasticsincollege,butduringmyfinalyearofhighschoolIbegantowonderwhatIshouldpursueforacareer.I attended the University of Massachusetts in Boston for one year and then transferred to BrandeisUniversity.Brandeis was an eye opening experience for me.For the first time in my life I was in aseriouslyintellectualenvironment.Theclassestendedtobesmall,intense,andstimulating.IdiscoveredthatIhadapassionforscience,andthatIwasverygoodatit.IchoseBiochemistryasamajorandanewly arrived assistant professor named Chris Miller for my honors thesis advisor.He had a littlelaboratorywithbigwindowsandlotsoflightshiningin.Istudiedcalciumtransportandlearnedaboutthecellmembraneasanelectrode.IcouldseethatChrisMillerwasamanhavinglotsoffuninhisdailylife and it was inspiring to me,and the memory of this stayed with me.But the biggest influenceBrandeishadonmylifehappenedinPhysicsclass.ThereImetmyfuturewifeAliceLee,whosesparklingeyesandsharpmindcaughtmyattention.AgainstChrisMillersadviceIwenttomedicalschoolafterBrandeis.IstudiedatTuftsUniversitySchoolofMedicineandthenatBethIsraelHospitalBostonforhouseofficertraininginInternalMedicine.IlearnedalotbutintheendIshouldhavetakenChrisadvicetopursuescience.Medicinerequiredalotofmemorizationandlittleanalyticalproblemsolving.TokeepacertainpartofmybrainactiveIbegantostudymathematics,andcontinuethiseventoday,learningnewmethodsandsolvingproblemswiththesamedisciplinedapproachIhadlearnedingymnastics.IstartedbacktoscienceneartheendofhouseofficertrainingworkingwithJimMorganstudyingcalciumincardiacmusclecontractility,whichwasveryenjoyableandkeptmeconnectedtomedicine.ButIhadayearningtoworkonaverybasicscienceproblem,whichmeantIwouldhavetobreakmymedicalties.ThiswasadifficultdecisionbecauseIhadinvestedsomanyyearsinmedicaleducation;toabandonitwastoadmittomyselfthatIhadmisspentabig piece of my life.And there were practical considerations as well.It was time finally to get apermanentjob;afterall,mywifeAlicehadsupportedmethroughyearsoftraining.NottomentionIwasnearly30yearsoldwithnorealbasicsciencetrainingbeyondmyBrandeisundergraduateeducation:wouldIevenbeabletomakeitasascientist?MyscientificcuriositytookaTwofactorshadthegreatestinfluenceonmydecision.BackinmyfirstyearofmedicalschoolIlostmysisterElley,anartistonlytwoyearsmysenior.DiagnosedwithleukemiaduringmyhematologyclerkshipasIlearnedaboutthedreadeddisease,shelastedonlytwomonths.Thishorrifyingeventimpresseduponmehowfragileandpreciouslifeis,andhowimportantitistoseizethemomentandenjoywhatyoudowhileyoucan.IrememberthinkingwhenIlookbackuponmylifeattheageofseventy,thirtywillseemyoung:justgoforit.AndthesecondfactorwasAlice.Shehadcompletefaithinmyabilitytosucceed.Nevermindthatpostdoctoralstudiesmeantareductionofmyalreadypiddlinghouseofficersalary.Shesimplysaidyouhavenochoice;wewillmanagesomehow.MemoriesofChrisMillerslaboratorybeckonedsoIreturnedforpostdoctoralstudies.OfcourseIwillneveroutlivehisremindingmethatIshouldhavelistenedtohiminthefirstplace.FeelingfarbehindinmyknowledgeIapproachedmypostdoctoralstudieswithintensity,learningtechniquesandtheory.IfeltIshouldbeanexpertinelectrochemistry,stochasticprocesses,linearsystemstheory,andmanymoresubjects.Ireadbooks,solvedtheproblemsets,masteredthesubjects,andcarriedoutexperiments.IhadtheverygoodfortuneofacoworkerJacquesNeyton,apostdoctoralscientistfromFrance.Jacquesisaverycriticalthinkerwhowouldbroodonaproblem.Weexchangedideasoften.WhenIwouldtellhimoneofmyideashehadatendencyjusttolistenquietly.Then,afterawhile,ifhisresponsestartedwithHeyRoddy,theressomethingIdontunderstandIknewIwasintrouble-myideawasprobablynogood!AfterIcompletedaseriesofbiophysicalstudiesonK+channelsitcametimetoapplyforanacademicposition.Duringthelate1980sphysiologydepartmentsweremoreinterestedinhiringchannelgeneclonersthanbio-physicists.ButPeterHessconvincedhiscolleaguesatHarvardthatmyworkshowedpromiseandIwasofferedanassistantprofessorshipthere.MylaboratorymadegoodprogressonK+channels.ItwasexcitingforawhilebutinjustafewyearsIbegantofeelthatthereturnonwhatwecouldlearnfromstudyingthefunctionaleffectsofmutationswasdiminishing.WehadidentifiedtheK+channelsignaturesequence,butwithoutknowingitsstructureweneverwouldunderstandthechemicalprinciples of ion selectivity in K+channels.I decided at that point to learn X-ray crystallography tosomedayseeaK+channel.TwofactorshadthegreatestiI began to learn methods ofprotein purification and X-ray crystallography while still atHarvard,initially working with channel toxins and a small soluble protein called a PDZdomain.However,IthoughtitbesttomoveawayfrommyfamiliarenvironmentatHarvardtopursuechannelstructure.Therewerereallytworeasonsmotivatingmetomove.Firstwas the practical issue of obtaining funding to work in an area in which I had nobackground:start-upfundsassociatedwithmovingtoanewuniversitywouldbeusefulforthispurpose.Thesecondandfarmoreimportantreasonwasthatmovingwouldenablemeto immerse myself completely in the new endeavor.A change of environment wouldremovethedistractionsofeverydaylife,isolatemefromthetemptationtofallbackonchannelphysiologystudiesthatIwasalreadygoodat,andallowmetofocuswithsingularpurposeonthestructuralstudies.IneededthistobecomeanexpertinmembraneproteinbiochemistryandX-raycrystallography,andtodevelopafeelforproteinstructure.WhenthepresidentofRockefellerUniversityTorstenWieselheardaboutmyscientificplanshesuggestedthatImovetoRockefellerUniversityandIdid.Rockefellerprovidedawonderfulenvironmentforconcentratingonadifficultproblem.IthasbeensaidthatgivingupmyalreadysuccessfullabatHarvardinordertopursuethestructureofaK+channelwasariskythingtodo.AtthetimeIwastoldthatmyaspirationswerealtogetherunrealistic.FrommyperspectiveIhadlittlechoicebecauseIwantedtounderstandK+selectivityandIknewthattheatomicstructureprovidedtheonlypathtounderstanding.I would rather fail trying than never try at all.It helped that I wasaccustomedtomakingtransitionsandhadbecomegoodatteachingmyselfnewsubjects.Ihavetoadmitthatfewpeopleworkingwithmeatthetimewantedmuchtodowiththenewendeavor-onlyonenewpostdoctoralscientistDeclanDoylewasenthusiastic.MywifeAlice,anorganicchemist,sawthatIwasgoingtobeprettylonelyanddecidedtojoinmeinthelab.Andtomygoodfortuneshehasworkedwithmesince.IhavelearnedthatmostpeopledonotlikechangebutIdo.Formechangeischallenging,goodforcreativity,anditdefinitelykeepslifeinteresting.IbegantolearnmethodsofprIthinkofthepasteightyearsofmylifeinNewYorkatRockefellerUniversityasapersonalodyssey.Thenewlaboratorystartedoutverysmall,withonlyDeclan,Aliceandme.Butitgrew in the first year with the addition of other enthusiastic postdoctoral scientists,includingJooMoraisCabralandJohnImredy.Workingwithmembraneproteinswasverydifficultasexpected.Wehadourperiodsofdespair,buteverytimewefeltleftwithoutoptionssomethinggoodhappenedanddespairgavewaytoexcitement.Persistenceanddedicationeventuallypaidoff.TheatomicstructureoftheK+selectivityfilterwasmoreinformativeandmorebeautifulthanIevercouldhaveimagined.Mylaboratorynowisanincredibleplace,overflowingwithexcitementandideassustainedbythecontinualinfusionofbrightyoungscientistswhocomefromaroundtheworldtoworkwithme.Itgivesmegreat satisfaction to know that these young scientists who are sophisticated in theirknowledgeofproteinchemistryandstructurewillleadthefieldofionchannelresearchintothefuture.Thishasbeenawonderfuladventure.IowethanksforthelifeIhave:toAlice,toallmylovingfamilyofMacKinnonsandLees,tomyscientificfamilyofstudents,postdocsand colleagues,to senior colleagues who have helped me along my way to pursue mypassion,andtotheRockefellerUniversity,theHowardHughesMedicalInstitute,andtheNationalInstitutesofHealthfortheirsupport.Iamverythankfulformylifeasascientist,fortheopportunitytounderstandinsomesmallwaytheworldaroundme.Ihopemybestexperimentandscientificideasareyettocome.Thishopekeepsmegoing.http:/www.nobelprize.org/nobel_prizes/chemistry/laureates/2003/mackinnon.htmlIthinkofthepasteightyear一、Generalproperties1.Valenceelectronofalkalimetals:(1)其氧化数为+1,不会有其它正氧化态。在无水无氧条件下,可以制得低氧化态的非寻常化合物。例如钠在乙二胺和甲胺中所形成的溶液也具有导电性,观察到Na-的光谱带,说明主要的导电体应是钠电离出的Na+和Na-。cryptand-222一、Generalpropertiescryptand-Inversesodiumhydride+H2Inversesodiumhydride+H2(2)由于价电子数少,所以碱金属原子之间的作用力比绝大多数其他金属原子之间的作用力要小,因此碱金属很软,低熔沸点,且半径大、密度小。Li的密度是所有金属中最小的,它的密度比煤油小。(2)由于价电子数少,所以碱金属原2.在形成化合物时,碱金属元素以离子键结合为特征,但也呈现一定程度的共价性。(1)气态双原子分子Na2、Cs2以共价键结合(2)Li的一些化合物共价成份最大,从LiCs的化合物,共价倾向减小。2.在形成化合物时,碱金属元素以离子键(3)某些碱金属的有机物,有共价特征。例如Li4(CH3)4甲基锂(3)某些碱金属的有机物,有共价特征。氢、碱金属和碱土金属课件二、Lithiumanditscompounds1.Generalproperties:Li的性质与碱金属有很大区别,但与碱土金属,特别是Mg的化学性质相似,这种关系称为对角线关系(diagonalrelationship)。Li与碱金属元素(Na、K、Rb、Cs)的区别:(1)锂的硬度比其它碱金属都大,但与碱土金属相似。(2)锂形成正常氧化物,而不形成过氧、超氧化合物。(3)锂与氮气形成氮化物,其他碱金属不能与N2直接化合,而碱土金属与N2能直接化合。(4)只有锂与碳反应生成Li2C2(乙炔锂),碱土金属都能形成MC2。(5)三种锂盐(Li2CO3、Li3PO4和LiF)溶解度小,碱土金属这三种盐的溶解度也小。二、Lithiumanditscompounds二、Lithiumanditscompounds1.Generalproperties:6.锂的有机金属化合物与镁的有机金属化合物相似7.许多锂的盐有高度的共价性,与镁相似。8.锂的氢氧化物、碳酸盐加热(与Mg相似)分解成氧化物和水或二氧化碳;其他碱金属的氢氧化物、碳酸盐加热难分解;而氢化锂加热不分解,氢化钠加热分解成氢气和气态Na2C2H5MgBr二、LithiumanditscompoundsC2H2.Thesimplesubstance(1)Lithiumisasoft,silverywhitemetal,thelightestofallmetals(2)preparation:电解LiCl(55%)KCl(45%)(3)与非金属反应.加热时,它直接与S,C,H2反应(4)在空气中被氧化,生成Li2O和Li3N;在CO2中加强热,可以燃烧(5)与金属反应,生成金属互化物2.Thesimplesubstance氢、碱金属和碱土金属课件(6)与H2O,H+剧烈反应,但在水中反应会减慢,由于LiOH溶解度小(7)它是Tritium的来源3.化合物(1)Li的二元化合物的化学性质、溶解度和水解性与相应的Ca、Mg化合物相似(2)LiF,Li2CO3,Li3PO4溶解度小(3)LiOH=Li2O+H2O这与其它碱不同,LiOH作为蓄电池的电解质Heat(6)与H2O,H+剧烈反应,但在水中反应会减慢,由He(4)锂盐与相类似的其他碱金属盐形成a.低共熔混合物LiNO3KNO3LiNO3NaNO3KNO3b.复盐M+LiSO4Na3Li(SO4)26H2O(5)过氧化物(peroxide)不是Li的特征(6)Li的某些矿物和人造化合物可用来制备珐琅,特殊玻璃(透过紫外光)(4)锂盐与相类似的其他碱金属盐形成GraphiteIntercalationCompounds(GICs)GraphiteIntercalationCompounGraphiteIntercalationCompounds(GICs)GraphiteIntercalationCompounGraphiteIntercalationCompounds(GICs)FromthefollowingarticleSuperconductivityintheintercalatedgraphitecompoundsC6YbandC6CaThomasE.Weller,MarkEllerby,SiddharthS.Saxena,RobertP.SmithandNealT.SkipperNaturePhysics1,39-41(2005)doi:10.1038/nphys0010GraphiteIntercalationCompounGraphiteIntercalationCompounds(GICs)Graphiteintercalationcompoundsareintercalationcompoundswithagraphitehost.Inthistypeofcompoundthegraphitelayersremainlargelyintactandtheguestmoleculesoratomsarelocatedinbetween.Whenthehostandtheguestinteractbychargetransferthein-planeelectricalconductivitygenerallyincreases.Whentheguestformscovalentbondswiththegraphitelayersasinfluoridesoroxidestheconductivitydecreasesastheconjugatedspsystemcollapses.Inagraphiteintercalationcompoundnoteverylayerisnecessarilyoccupiedbyguests.Inso-calledstage1compoundsgraphitelayersandintercalatedlayersalternateandinstage2compoundstwographitelayerswithnoguestmaterialinbetweenalternatewithanintercalatedlayer.Theactualcompositionmayvaryandthereforethesecompoundsareanexampleofnon-stoichiometriccompounds.Itiscustomarytospecifythecompositiontogetherwiththestage.PotassiumgraphiteisdenotedasKC8andisoneofthestrongestreducingagentsknown.Itispreparedunderinertatmospherebymeltingpotassiumovergraphitepowder.Thepotassiumisabsorbedintothegraphiteandacolorchangefromblacktobronzeisobserved.Theresultingsolidisalsoquitepyrophoric.Structurally,compositioncanbeexplainedbyassumingthatthepotassiumtopotassiumdistanceistwicethedistancebetweenhexagonsinthecarbonframework.Thebondbetweengraphiteandpotassiumatomsisionicandthecompoundiselectricallyconductive.GraphiteIntercalationCompoun氢、碱金属和碱土金属课件氢、碱金属和碱土金属课件Bythistime,ateamofresearchersledbyJohnGoodenough,nowattheUniversityofTexas,haddiscoveredanewfamilyofintercalationcompoundsbasedonoxidesofmanganese,cobaltandnickel.Thefirstcommerciallithium-ionbattery,launchedbySonyin1991,wasarocking-chairdesignthatusedlithium-cobalt-oxideforthepositiveelectrode,andgraphite(carbon)forthenegativeone.Thistypeofbatteryisnowinwidespreaduse,andDrGoodenoughwasawardedthe$450,000JapanPrizein2001inrecognitionofhiswork.Bythistime,ateamofresearThedevelopmentofthelithium-ionbatteryisanobjectlessoninhowpureandappliedresearch,drivenbycommercialinterests,cangeneratetheincrementalimprovementsinatechnologythatarenecessaryfortransformingitintoausefulproduct.Inthiscase,intercalationcompoundswereanoffshootofpureresearchintosuperconductivity.TheywerethenpickedupbyDrGoodenoughandotherresearchersworkingonbatterytechnology;andthefinalpiecesofthepuzzleweresuppliedbySony.(DrGoodenough,whodidhisoriginalresearchatOxford,saysbatteryfirmsintheWestrejectedhisapproaches.)Thedevelopmentofthelithium三、Sodiumanditscompounds1.Existence:2.Thesimplesubstance(1)与O2反应(过氧化物):一般2Na+O2=Na2O2要得到Na2O需要Na2O2+2Na=2Na2O(2)熔融的钠与S反应2Na+XS=Na2Sx(3)钠与NaOH(l)反应2Na+NaOH=Na2O+NaH(4)氨合电子三、Sodiumanditscompounds3.化合物(1)NaHCO3的溶解度小于Na2CO3的溶解度,可以用氨氯法制备NaCl+NH4HCO3=NaHCO3+NH4Cl(2)Na2CO3的制备:Na2SO4(s)+2C(石墨)+CaCO3(s)=CaS(s)+Na2CO3(s)+2CO2(g)(3)Na2S可溶解单质S形成Na2Sx呈现黄色Na2S+(X-1)S=Na2Sx(4)OrganometallicCompounds3.化合物联合制碱法又称侯氏制碱法,用于在工业上制取纯碱(Na2CO3)由侯德榜于1943年发明,是世界上广泛采用的制纯碱法。联合制碱法建立在氨碱法的基础上,反应不同点在于:在氨碱法的废液中加入氯化钠,并在3040C下向废液中通入二氧化碳和氨气,使溶液达到饱和态,然后降温到10C以下,由于氯化铵在30C时的溶解度比氯化钠大,而在10C下比氯化钠溶解度小,以及同离子效应,使氯化铵从母液析出,其母液又可作为下一次制碱的原料,氯化铵也可以作为一种化肥。蒸乾得到碳酸钠。主要反应方程式为:NH3+CO2+H2O+NaCl=NH4Cl+NaHCO32NaHCO3-加热Na2CO3+CO2+H2O所谓“联合制碱法”中的“联合”,指该法将合成氨工业与制碱工业组合在一起,利用了生产氨时的副产品CO2,革除了用石灰石分解来生产,简化了生产设备。此外,联合制碱法也避免了生产氨碱法中用处不大的副产物氯化钙,而用可作化肥的氯化铵来回收。联合制碱法也存在不足。较氨碱法而言,它的用氨量较大,在有些情况下不适用。维基百科联合制碱法又称侯氏制碱法,用于在工业上制取纯碱(Na2CO3四、PotassiumSubgroup(钾族元素)1.K,Rb,Cs是最典型的金属,形成化合物时离子键特征最显著,而配合物、晶体水合物不是钾族元素的特征2.Thesimplesubstances(1)除了Cs是goldenyellow外,其它都是lustrous,silverywhite,软,密度低,K比水轻,存放在煤油中。四、PotassiumSubgroup(钾族元素)(2)与非金属反应a.与S反应:用过量的S与碱金属硫化物煮沸或熔融的硫化物与S反应,形成M2Snb.与氧反应(超氧化物)(i)与O2反应:M+O2=MO2在液氨中MO2是红色晶体同样MO2+M=M2O2MO2+3M=2M2O(2)与非金属反应(ii)与O3反应(臭氧化物):MO36KOH(s)+4O3(g)=4KO3(s)+O2(g)+2KOH.H2O(s)(iii)它们都不稳定2KO2+2H+=2K+H2O2+O22KO3=2KO2+O2KO3在水中迅速分解4KO3+2H2O=4K+4OH-+5O2c.与Br2反应发生爆炸(ii)与O3反应(臭氧化物):MO3(3)与金属反应,主要生成金属互化物(金属间化合物)(IntermetallicCompounds)(4)与H2O反应:Rb,Cs与水反应发生爆炸(5)制备:KCl(l)+Na(g)=NaCl(l)+K(g)(850degC)由于K的沸点小于Na,使反应向右进行在液氨中2KCl+Ca=CaCl2+2K由于CaCl2不溶于液氨,使反应向右进行(3)与金属反应,主要生成金属互化物(金属间化合物)3.化合物(1)溶解性:与Li+,Na+相似的化合物相反,MClO4,M2PtCl6溶解度小(barelysolable)(2)硝酸盐热分解性:3.化合物3碱土金属及其化合物Alkali-earthmetalsandtheircompoundsBerylliumMagnesiumCalciumBeMgCaStrontiumBariumRadiumSrBaRa3碱土金属及其化合物一、通性Generalproperties:1.碱土金属显示+2氧化态2.性质递变规律与碱金属一致二、Berylliumanditscompounds1.性质与Al相似,是典型的两性金属,在通常情况下,不形成简单离子,而形成正负配离子Be3Al2(SiO3)6一、通性Generalproperties:Be32.Thesimplesubstance(1)密集的六方金属晶体,表面易形成氧化层,减小金属本身的活性(2)与非金属反应2Be+O2=2BeOBe+S=BeS3Be+N2=Be3N2(3)两性Be+2H3O+2H2O=Be(H2O)42+H2Be+2OH-+2H2O=Be(OH)42-+H2Be对冷的浓HNO3和浓H2SO4起钝化作用2.Thesimplesubstance(4)与金属反应:Be与d区元素反应生成金属间化合物:MBe12,MBe11,也可作为合金添加剂(alloyingadditive),使合金耐腐蚀,增加强度和硬度。(5)Preparation:BeCl2+Mg=MgCl2+Be热还原法(4)与金属反应:Be与d区元素反应生成金属间化合氢、碱金属和碱土金属课件3.化合物Be(II)(1)BeO、BeS都具有两性,Be(OH)2,Be(hal)2也有两性,例如:BeO+SiO2=BeSiO3BeS+SiS2=BeSiS3BeO+Na2O=Na2BeO2BeS+Na2S=Na2BeS22KF+BeF2=K2BeF4BeF2+SiF4=BeSiF6(2)BeS彻底水解BeS+H2O=Be(OH)2+H2S Be3N2也彻底水解3.化合物Be(II)(3)BeCl2呈纤维状结构(fibrousstructure)为什么熔融态的BeCl2导电能力低于CaCl2?2BeCl2=BeCl3-+BeCl+CaCl2=Ca2+2Cl-即不形成单个离子,而形成配离子。(4)BeCO3,Be3(PO4)2难溶于水,但形成复盐后可溶,也可溶解在IA或铵的碳酸盐饱和溶液中。(NH4)2CO3+BeCO3=(NH4)2Be(CO3)2Berylliumcompoundsarepoisonous!与碳酸根配位(3)BeCl2呈纤维状结构(fibrousstru三、Magnesiumanditscompounds1.镁的性质明显不同于铍,原子、离子半径差别大,即镁的金属性比铍、铝强。在自然界中以硅酸盐和碳酸盐矿存在。2.Thesimplesubstance(1)白色金属,软,比Be有弹性,在空气中被氧化呈暗色。单质具有强还原性。三、Magnesiumanditscompounds(2)MgOMgX2O2X2MgN2SMg3N2MgSMg不能直接与H2反应MgH2只能间接获得。如通过MgBr2与NaH反应或烷基镁热分解等。(3)镁主要用于合金(2)MgOMagnesiumalloydevelopmentshavetraditionallybeendrivenbyaerospaceindustryrequirementsforlightweightmaterialstooperateunderincreasinglydemandingconditions.Magnesiumalloyshavealwaysbeenattractivetodesignersduetotheirlowdensity,onlytwothirdsthatofaluminium.Thishasbeenamajorfactorinthewidespreaduseofmagnesiumalloycastingsandwroughtproducts.Afurtherrequirementinrecentyearshasbeenforsuperiorcorrosionperformanceanddramaticimprovementshavebeendemonstratedfornewmagnesiumalloys.Improvementsinmechanicalpropertiesandcorrosionresistancehaveledtogreaterinterestinmagnesiumalloysforaerospaceandspecialityapplications,andalloysarenowbeingspecifiedonprogrammessuchastheMcDonnellDouglasMD500helicopter.KeyProperties Light weight Low density(two thirds that of aluminium)Good high temperature mechanical properties Good to excellent corrosion resistanceApplications:aerospace,motorracing,bicycle,etc.Magnesiumalloyde
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