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1、正溴丁烷的制备思考题(Preparationofn-bromobutane)tetrabromobutane1.Whatistheroleofsulfuricacidinthisexperiment?Theamountofsulfuricacidandtheconcentrationistoolargeortoosmallwhatisnotgood?Answer:actionis:reactant,catalyst.Whentoolarge,thereactiongeneratesalargeamoun
2、tofHBrrunningout,andeasytooxidizebromineiontobromine;Afteranhour,thereactionisincomplete.2.Whatimpuritiesmaybeintheproductsafterthereaction?Whatisthepurposeofeachstepwashing?WhydoIneedtouseadryseparatoryfunnelwhenwashingwithconcentratedsulfuricacid?A:itm
3、aycontainimpurities:n-c4h9oh,(n-c2h5),HBrEachstepofwashingpurposes:(1)waterinadditiontothesixHBr,mostofthen-C4H9OH(2)sulfuricacidwash(n-C4H9)2o,therestofthen-C4H9OH(3)formost-H2SO4(4)useNaHCO3washwithwaterinadditiontotherestofthe-H2SO4(5)finallywashedwit
4、hwaterexceptNaHSO4residues,suchasexcessiveNaHCO3.Withconcentratedsulfuricacidwashing,thepurposeofusingthedryseparatoryfunnelistopreventtheconcentrationofsulfuricacidandinfluencethewashingeffect.If1-bromobutanecontainingn-butylalcoholdistillationwillformb
5、eforefractions(1-bromobutane-n-butylalcoholconstantboilingpoint98.6℃,inclusiveofour13%n-butylalcohol),andresultsinthedecreaseofrefinedproductionrate.3.Theproductiswashedwithaliquidfunnel.Theproductissometimesintheupperandlowerlayers.Whatistheeasiestwayto
6、judge?Answer:pouralittlebitofsuperfluidfromthesplitfunnelorreleasealittlebitofthelowerlevelliquidinawatertesttubetoseeifthereisanyoilbeadappearingtojudge.4.Whydoyouneedtowashwithwaterbeforewashingwithsaturatedsodiumbicarbonatesolution?Answer:firstwashedw
7、ithwater,canremovepartofsulfuricacid,topreventwashwithsodiumbicarbonate,sodiumbicarbonateandsulfuricacidreactiontogeneratealargeamountofcarbondioxidegas,makethestressintheseparatoryfunnel,leadtothepiston,thenwashwithsaturatedsodiumbicarbonatesolutioncanf
8、urtherremovethesulfuricacid.Thewashingvibrationprocessshouldpayattentiontothegas!5.WhyshouldIreleasetheproductintimewhenIwashtheproductwithaliquidfunnel?HowshouldIoperate?A:duringthisprocess,thegaswillbeproducedaftershakin