Group14Shriver,Chapter13C,Si,Ge,Sn,PbC,Siarenon-metalsGeisametalloidSn,PbaremetalsChemicalhardnessdecreasesdownthegroup(C,Si:oxophilic,fluorophilic)Majoroxidationstate+4exceptforlead:Pb(II)Pbformsmoststablecomplexeswithsoftanions:S,IMetallicpropertiesincreasedownthegroupCarbonMostabundantformintheatmosphere:CO2,andintheEarth’scrust:MCO3Elementalformsknownsinceprehistory:charcoal,soot(usedininks),diamond,graphiteNamecoinedbyLavoisierfromcarbo(Latin,charcoal)Naturallyoccurringformsoftheelement(allotropes)aregraphite(Greekgraphein,towrite)anddiamond(fromGreekdiaphanes(transparent)withadamas(indomitable))First‘lead’pencilsmanufactured1564containedgraphite(theystilldo)Newallotropediscovered1985,inmolecularbeamexperiments:C60,C70,C76,C84namedbuckminsterfullerenes,forthearchitectRichardBuckminsterFuller,whodesignedgeodesicdomeshavesincebeenfoundtooccurnaturallyincandlesoot,lightningdischargesnowcalledfullerenes,orbuckyballsC60structureisatruncatedicosahedron,20hexagonsand12pentagons,approx.1nmindiameterelongatedversions:carbonnanotubes,concentriccylinderofhexagons,withbuckyballends,ofinterestinhydrogenstorageMajorusesofCare:asafuel(coal),asareducingagentformetalores(coke),diamondcuttingtoolsasalubricant(graphite),alsoinpencils,fuelcellanodesImportantusesofCinscience:13CNMR,14Cradio-carbondatingSilicon26%oftheearth’scrustbyweight,mostabundantelementafterOfoundinsand,quartz,clay,etcnamefromtheLatinsilicis(flint)forPaleolithictools(fromsilicaandsilicates)elementfirstisolatedin1823byreducingK2SiF6withKnowmadebySiO2+2C+heatSi+2COasemiconductor,usedinmicroelectronicsindustryoneofthepurestmaterialsmadeonanindustrialscale,impuritiesca.10-10routine1Germaniumeka-siliconpredictedbyMendeleevdiscoveredin1886byWinkler,inraremineralargyroditeAg8GeS6namedinhonorofGermanylowabundance,likeGamajorsourcetoday:recoveryofGeO2fromfluedustofsmeltersprocessingZnoresasemiconductor,likeSi,butwithasmallerbandgapusedinIRtransparentwindows