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PreparationofethylacetateFirst,thepurposeoftheexperiment:1、Learnfromthegeneralprinciplesoforganicsyntheticestersandmethods2、Masterdistillation,extraction,dryingandotherexperimentaltechniquesanditsapplicationinaspecificexperimentSecond,theexperimentalprinciple:Mainreaction：CH3COOH+CH3CH2OH=CH3COOCH2CH3+H2OConditions:heatingto120to125°CinconcentratedsulfuricacidcatalyzedSideeffects：浓H2SO4CH3CH2OH---------CH2=CH2+H2O170度浓H2SO4CH3CH2OH---------CH3CH2OCH2CH3+H2O140度Third,theinstrumentsandreagents:1、Instrumentsandmaterials:Round-bottomedflask,Sphericalcondenser,Straightcondenser，Distillationhead,aseparatoryfunnel,measuringbeakers,dropper,conicalflask,thermometer,electric2、drugs:Glacialaceticacid(AR),absoluteethanol(AR),concentratedsulfuricacid,saturatedbrine,asaturatedsodiumcarbonatesolution,asaturatedcalciumchloridesolution,driedoveranhydrousmagnesiumsulfate,litmusFourth,Reactor：Fifth,Experimentalprocedure:Adding50mlroundbottomflask3ml5mlethanolandaceticacid,inshakingbatchofconcentratedsulfuricacidwasadded1.3mlmixed,andaddafewgrainsofzeolite,andtheninstalltheinstrumentresponseLowheat,slowlyrefluxfor30minutes.Coolish,refluxdevicetothedistillationapparatus,wettedwithcoldwatertocoolthebottle.HeatingdistillationuntilthedistillateliquidvolumeisabouthalfthevolumeofthereactionsofartogivethecrudeproductinethylacetateThedistillatewasslowlysaturatedsodiumcarbonatesolutionwasaddedportionwise,andoscillateuntiltheevolutionofcarbondioxidegaswithoutusinglitmuspapertestacetatelayerwasneutral.Themixturewasthentransferredtoaseparatoryfunnel,andseparatedaqueouslayerwaswashedoncewithsaturatedaqueoussalinesolution3mlTheorganiclayerwaswashedwithasaturatedsolutionofcalciumchloride3ml,washedwithwaterandfinallyonce.TheorganiclayerinadryErlenmeyerflaskfilledwithanhydrousmagnesiumsulfate.Thecrudeethylacetate,driedonawaterbathheatedtodistill,collectingfractions73to78°C.Weighormeasureproductvolume,andcalculatetheyieldpointorrefractiveindexmeasurementproductsSix,Discuss:1、Abletouseinplaceofaconcentratedsodiumhydroxidesolutionwaswashedwithasaturatedsolutionofsodiumcarbonatedistillate?Cannot.Becauseastrongbaseissodiumhydroxide,theproductcausesthehydrolysisofethylacetate,therebyreducingtheyieldof