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1、Chem104LaboratorySynthesisofAspirinReference:ChemistryforaModernSocietyLaboratoryManual,WayneM.Stalick,2003,Pages121-127.Data:Afteryouaredonewiththeexperimentandhaverecordedtheweightoftheaspirinyousynthesizedinthelabenteryourdataintothedatabase.Inyourmeas
2、urementsandcalculationspayacloseattentiontouncertaintiesandsignificantfigures.Results:Outsideoftheclassyouareabletoretrieveyourdataalongwiththatoftheentireclassbygoingtothewebsitehttp://chem.gmu.edu/modresults/andenteringyourID(yourGMUemailaddress)andpass
3、word(yourSS#).TheretrievalpageisintheformofanExcelspreadsheet.YouneedtouseExceltocalculatethemolesofsalicylicacidandaceticanhydrideinadditiontothetheoreticalyieldandpercentyieldofaspirin.YourExcelreportshouldincludethefollowing:·ThedownloadedretrievalExce
4、lspreadsheetcalled“Rawdata”whichshowsthedatafortheentireclass.Makesurethatyouroundthenumbersineachcolumntotheappropriatesignificantfigures.AtypicalexampleofaRawDatasheetisshownbelow:Table1:RawDataABC1Weightofsalicylicacid(g)Volumeofaceticanhydride(ml)Weig
5、htofisolatedAspirin(g)23.255.303.3233.145.822.89·Youneedtoshowyourcalculatedresultsandgraphonaseparatespreadsheetcalled“ClassResults”.GotoSheet2oftheExceldocumentandrightclickonthistabandnameitClassresults.Hereisanexampleofsuchsheet:Table2:ClassResultsABC
6、DEFG1Molesofsalicylicacid(Mole)Weightofsalicylicacid(g)Molesofaceticanhydride(Mole)Volumeofaceticanhydride(ml)Theoreticalyieldofaspirin(gram)Weightofisolatedaspirin(gram)%Yield20.02353.250.05615.304.243.3278.330.02273.140.06165.824.092.8970.6Inordertocalc
7、ulatethenumberofmolesofsalicylicacidyouneedtodivideitsweight(cellB2)withitsformulamass(138.12g/mol).Todothistype=B2/138.12incellA2thenhitenter.TocalculatemolesofsalicylicacidfortherestofdatapointsincolumnBgototherightcornerofcellA2anddragitdown.Tocalculat
8、ethenumberofmolesaceticanhydridefromitsvolume(cellD2)youneeditsdensity(1.08g/ml)anditsformulamass(102.09g/mol).BytypingthefollowingformulaincellC2youwillgetthemoleofaceticanhydride:=(D2*1.08)/102.06.Gotothelowerrigh