18-Additional Aspects of Acid-Base Equilibria .pdf

《18-Additional Aspects of Acid-Base Equilibria .pdf》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。

1、Chemistry140Fall2002Chapter18:AdditionalAspectsofAcid-BaseEquilibriaContents18-1TheCommon-IonEffectinAcid-BaseEquilibria18-2BufferSolutions18-3Acid-BaseIndicators18-4NeutralizationReactionsandTitrationCurves18-5SolutionsofSaltsofPolyproticAcids18-6Acid-BaseEquilibriumCalculations

2、:ASummaryFocusOnBuffersinBloodSlide2of421Chemistry140Fall200218-1TheCommon-IonEffectinAcid-BaseEquilibria(酸碱平衡中的同离子效应)•Considerasolutionthatcontainsboth0.100MCHCOHand0.100MHCl.32CH3CO2H+H2O¾CH3CO2-+H3O+(0.100-x)MxMxMHCl+H2O¾Cl-+H3O+0.100M0.100M[H3O+]=(0.100+x)Messentiallyalldueto

3、HClSlide3of42AceticAcidandHydrochloricAcid0.1MHCl0.1MCH3CO2H0.1MHCl+0.1MCH3CO2HSlide4of422Chemistry140Fall2002Example18-1DemonstratingtheCommon-IonEffect:ASolutionofaweakAcidandaStrongAcid.(a)Determine[H3O+]and[CH3CO2-]in0.100MCH3CO2H.(b)Thendeterminethesesamequantitiesinasolutio

4、nthatis0.100MinbothCH3CO2HandHCl.RecallExample17-6(p680):CH3CO2H+H2O→H3O++CH3CO2-[H3O+]=[CH3CO2-]=1.3×10-3MSlide5of42Example18-1CH3CO2H+H2O→H3O++CH3CO2-Initialconcs.weakacid0.100M0M0Mstrongacid0M0.100M0MChanges-xM+xM+xMEqlbrmconc.(0.100-x)M(0.100+x)MxMAssumex<<0.100M,0.100–x≈0.10

5、0+x≈0.100MSlide6of423Chemistry140Fall2002Example18-1CH3CO2H+H2O→H3O++CH3CO2-Eqlbrmconc.(0.100-x)M(0.100+x)MxMAssumex<<0.100M,0.100–x≈0.100+x≈0.100M[H3O+][CH3CO2-]x·(0.100+x)Ka==[C3CO2H](0.100-x)x·(0.100)-5==1.8×10(0.100)[CH3CO2-]=1.8×10-5Mcomparedto1.3×10-3M.LeChatellier’sPrincip

6、leSlide7of42SuppressionofIonizationofaWeakAcidSlide8of424Chemistry140Fall2002SuppressionofIonizationofaWeakBaseSlide9of42SolutionsofWeakAcidsandTheirSaltsSlide10of425Chemistry140Fall2002SolutionsofWeakBasesandTheirSaltsSlide11of42TheCommon-IonEffect•TheCommon-IonEffectisthesuppre

7、ssion(抑制)oftheionizationofaweakelectrolytecausedbyaddingmoreofanionthatisaproductofthisionization.Slide12of426Chemistry140Fall200218-2BufferSolutions(缓冲溶液)•1.0mlof1.0MHClisaddedto100mlofsolutioncontainsHAcandNaAc(bothconcentrationsare0.1M).CalculatethechangeofpHduringtheprocess,a

8、ndcompareitwiththatofthesameamountofHCla