acid-base titration - distance education @ ncssm：酸碱滴定法-远程教育”组成的

《acid-base titration - distance education @ ncssm：酸碱滴定法-远程教育”组成的》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、Acid-BaseTitrationCurvesNAME:________________________________________PERIOD:___________PrelabShowCalculations.1.Forthetitrationof50.0mlof0.100Maceticacidwith0.200MNaOH,usingaKaof1.76x10-5,calculatethepH:a.Initial(0mlofNaOHadded):b.Atthehalfequivalenc

2、epoint:c.Attheequivalencepoint:d.15mlbeyondtheequivalencepoint:2.Whatisthedifferencebetweentheendpointinatitrationandtheequivalencepoint?3.Doestheuseofaweakacidindicatorhavemucheffectontheaccuracyoftheendpointofatitration?Whyorwhynot?12Acid-BaseTitra

3、tionCurveswebversion02-03Acid-BaseTitrationCurvesThreeimportanttypesofacid/basereactionswillbeinvestigatedinthislab.ThechangeinpHwhenastrongacidistitratedwithastrongbase,whenaweakacidistitratedwithastrongbase,andwhenaweakbaseistitratedwithastrongacid

4、.Eachwillhaveacharacteristicshapewhenthetitrationcurveisplotted,thatis,thepHisplottedonthey-axisandthevolume(mL)ofaddedtitrant(thesolutionintheburet)isplottedonthex-axis.AtitrationcurveallowsonetoexperimentallydeterminetheKaforaweakacidortheKbforawea

5、kbase.ThepHwillbemeasuredusingapHprobeattachedtoaCBLandgraphingcalculator.Inthetitrationofastrongacidwithastrongbase,hydrochloricacid,HCl,willbereactedwithsodiumhydroxide,NaOH.TheconcentrationoftheNaOHsolutionwillbegivenandyouwilldeterminetheunknownc

6、oncentrationoftheHCl.ThisisreferredtoasstandardizingtheHClsolution.HClreactswithNaOHinaone-to-onemoleratiotoproducewaterintheoverallreaction:HCl(aq)+NaOH(aq)®H2O(l)+NaCl(aq)TheHClionizes100%andtheNaOHdissociatescompletelyinwatersolutiongivingtheionic

7、equation:H+1(aq)+Cl-1(aq)+Na+1(aq)+OH-1(aq)®H2O(l)+Na+1(aq)+Cl-1(aq)Removingthespectatorionsgivesthenetionicequation:H+1(aq+OH-1(aq)®H2O(l)TheequivalencepointforastrongacidstrongbasetitrationwillbepH7sincetheNa+1ionandtheCl-1(theconjugatebaseofastron

8、gacid)donotundergohydrolysis.ThepHofthesolutionisthereforethepHofpurewater.ThevolumeofNaOHsolutionusedtoreachtheequivalencepointwillbeusedtodeterminethemolarityoftheHCl.AmonoproticweakacidreactswithNaOHinaone-to-oneratiotoproducewaterandtheconjugateb