高中化学必修1 第四章知识点

高中化学必修1第四章知识点（Highschoolchemistry1chapter4knowledgepoints）ThefourthchapterThefirstsectionofsiliconInnature,siliconisintheformofsilicaandsilicates,andthereisnosuchthingassiliconThepropertiesofsilicondioxide:highmeltingpoint,largehardnessandinsolubleinwater1.Silicaisacidicoxide:canreactwithalkalioralkalineoxideSiO2naoh+2=Na2SiO3+H2OTheformationofsodiumsilicateismoreviscous,sotheglassreagentoftheacidsolutionisnotusedfortheglass,andtherubberplugisusedSiO2+CaO=CaSiO3HydrofluoricacidistheonlyacidthatreactswithsilicondioxideSiO2+4HF=SiF4arrow+H2OHydrofluoricacidcancorrodetheglassandcanbeusedtosculpttheglass,whichcan'tbeusedinglassreagentbottles,butplasticbottles.Applicationofsilica:fiberoptics,silicon,glass,handicraft(quartz,crystal,agate)Thepreparationofsilicicacid:Na2SiO3+2HCl=2NaCl+H2SiO3SilicicacidisawhitecolloidalsolidthatisinsolubleinwaterandismoreacidicthancarbonatedTothesodiumsilicatesolution,thecarbondioxideisformedinwhitesilicateNa2sio3+CO2+H2O=Na2CO3+H2SiO3SilicagelcanbedesiccantafterdehydrationTheaqueoussolutionofsodiumsilicateiscalledwaterglass,whichcanbeusedassoapfiller,woodfireretardantandadhesive.Note:thewaterglass(i.e.,sodiumsilicatesolution)issensitivetotheCO2reactionintheairandproducesH2SiO3.ItshouldbesealedandpreservedApplicationofsilicate:ceramic,glassandcementSimplesilicon:properties:metallicblacksolidwithmetallicluster,highmeltingpoint,highhardness,stableatnormaltemperatureMethod:NormaltemperaturecanreactwithalkalisolutionandHFSi+naoh+2H2O+2==Na2SiO3h2writeSiplus4HF=SiF4+2H2USES:Semiconductormaterials,photovoltaic(computerchips,semiconductortransistors,)Sectioniitheelementofenrichmentinseawater-chlorine1.Thepresenceofchlorine:innaturechlorineexistsmainlyinseawater,mainlyinCl-form.2.Physicalpropertiesofchlorinegas:agaswithapungentsmellandpoisonousyellowandgreen,Itissolubleinwater(1:2),lowtemperatureandeasytoliquefywhenpressurized.3.Chemicalpropertiesofchlorinegas:A,chlorinegasandmetalreactions2Na+Cl2==2NaCl(yellowflame,whitesmoke)Cu+Cl2==CuCl2(palmyellowsmoke,asmallamountofwaterwithagreensolution,suchasalargeamountofwaterinblue)2Fe+3Cl2==2FeCl3(notgeneratingFeCl2)(brownsmoke)B,chlorinegasandnonmetallicreactionsH2+Cl2===2HCl(whitefog)(explosionunderlightofCl2andH2)2P+3Cl2(asmallamount)==2PCl3(whitefog)(whitesmokewhenchlorineandParelit)2P+5Cl2(lots)==2PCl5(whitesmoke)(combustion:theintensechemicalreactionofanyglowingheatiscalledcombustion.Combustiondoesnothavetobeoxygentoparticipate.ThenatureofcombustionistheREDOXreaction.)C,chlorineandwaterCl2+H2O═HCl+HClO(Cl2dobothoxidantandreducingagent)Hypochlorousacid(HClO)unaryweakacid(acidisweakerthancarbonicacid),strongoxidation(sterilization,disinfection),bleaching,unstableandeasytodecompose.2HClO==2HCl+O2Newchlorinewatercomposition(particle):Cl2,H2O,HClO,H+,Cl-,ClO-Chlorinewatercomposition(particle):H2O,H+,Cl-Drychlorinegasisnotbleached,andtheessenceofbleachingisHClOinchlorinewater.D,thereactionwithabasesolutionCl2+2OHminus==Cl-+ClO-+H2O(usingsodiumhydroxidetoabsorbexcessCl2)Theingredientsofbleach,CaCl2andCa(ClO)2Theactiveingredientofbleachingpowder,Ca(ClO)2Bleachingprincipleofbleachingpowder:theprocessofproducinghypochlorousacidbycontactwithCO2intheair.E.Reactionofchlorinegastoothercompounds(strongoxidant):ReductivesubstancessuchasFe2+,Br-,I-,SO2,SO32-...Thesubstancecanbeoxidizedbychlorinegas.2fecl2+Cl2fecl3==22nabr+nacl+Br2Cl2==22nai+Cl2nacl+I2==2H2S+Cl2==S+2HCLNa2SO3+H2O+nacl+-H2SO4Cl2==2F.LaboratorypreparationofchlorinegasSection3oxidesofsulfurandnitrogenSulfur:yellowpowder,insolubleinwater,solubleinalcohol,solubleinCS2.Sandmetalreactwithmetalsulfide(suchasCu2S,FeS,etc.)SO2:colorless,pungentandpungent,noxiousgas,withadenserthanair,easytoliquefy,easytodissolveinwater,1volumeofwaterdissolvedin40volumesofSO2.It'stheacidanhydrideofH2SO3.SO2+H2OH2SO3SO2+Ca(OH)2=CaSO3+H2OThebleachingofSO2makesthemagentacolorfade,thenon-oxidizedreductionreaction,temporary,canonlymakethepurplelitmustestliquidred,cannotmakeitfade.SO2canbeusedtokillbacteria.TheweakoxidationofSO2:SO2+2H2S=3S+2H2OStrongreducibilityofSO2:SO2+Br2+2H2O=H2SO4+2HBr(discolorationofbromine)SO2+Cl2+2h2o+2=-H2SO4HCL(SO2withchlorinewaterintothecoloredsolutionsuchasmagenta-bleaching,ornobleaching)5SO2+2KMnO4+2H2O=K2SO4+2MnSO4+2H2SO4(notmemory)(knowingthatSO2candiscolortheKMnO4solution,SO32-withH+,KMnO4-can'tcoexistinthesolution)SO2+O2SO3SO2test:applySO2tobromine,KMnO4solutionandmagentasolutiontoseeifitfades.Remove(SO2orHClgas)fromCO2andusesaturatedNaHCO3solutionCheckforCO2andSO2inthemixtureofgases:firstthroughmagenta-thenthroughKMnO4-throughmagenta-andthenpassthroughtoclarifythelimewater.SO2onlyreactswithBa(NO3)2solutionandproduceswhiteprecipitation.Itdoesn'treactwithBaCl2.3SO2+3Ba(NO3)2+2H2O=3BaSO4+4HNO3+2NO(theequationdoesnothavetoberemembered)Redandbrownpungentsmellpoisonousgas,denserthanair,easytoliquefy,easytodissolveinwaterThevalenceofN:-3,0+1+2+3+4+5N2O5istheanhydrideofHNO3,andN2O3istheanhydrideofHNO2,4no2+2h2o+O2=4hno34noO2+2h2o+3=4hno3Thefourthsulfuricacid,nitricacidandammoniaDilutesulfuricacidwithacidity:withacid-baseindicatorandreactivemetalreactiontogenerateH2,whichreactswithmetaloxidetoformsaltandwater,Thesaltreactionproducesanotheracidandsalt(thestrongacidweakacid)andneutralizesthebaseStrongH2SO4andHNO3reactwithmetalbutnotH2.Concentratedsulfuricacid:1concentratedsulphuricacidisacolorlessoilliquid.Sulfuricacidisastrongacidwithhighboilingpoint,whichiseasytodissolveinwaterandcanbemixedwithwateratanyrate.Concentratedsulfuricacidwillgiveoffalotofheatwhendissolvedinwater.2.ItcanbeusedtodryH2,O2,N2,CO,CO2,CH4,SO2,HCl,Cl2,etc.,whichcannotbeusedtodryNH3,H2S,HIandHBr.Strongoxidizing:metalsandnonmetalsthatcanbeoxidized.2H2SO4(thick)+Cu=CuSO4+2h2o+SO22H2SO4(thick)+C=CO2+2SO2+2H2O(howtotestthegasproduced,seethepreviousSsection)Nitricacid:1instability:(easytodecompose)4HNO3==4NO2arrow+2H2O+O2arrowStrongoxidation4HNO3(thick)+Cu==Cu(NO3)2+2NO28HNO3(dilute)+3Cu==3Cu(NO3)2+2NOupUndernormaltemperature(cold)thickH2SO4orstrongHNO3willmaketheactivemetalpassivate(suchasaluminumandiron),sotheirontankcanbeusedtotransportthick