Chemistry 12 Name: Acid-Base Part II Practice Test Date ...
Transcript of Chemistry 12 Name: Acid-Base Part II Practice Test Date ...
Chemistry12
Acid-BasePartIIPracticeTestName:Date:Block:
MultipleChoice._________1.Whichtermdoesthefollowingstatementbestdescribe?Amixtureofaweakacidanditsconjugatebase,eachwithdistinguishingcolours.
A.Buffer B.TitrationC.IndicatorD.Primarystandard
_________2.WhichofthefollowingpropertiesistrueforasolutionofKNO3?
A.Itisneutral B.ItisbasicC.ItisslightlybasicD.Itisslightlyacidic
3.Explainyouranswertothequestionabove:_________4.Whichofthefollowingsaltswillbebasic?
A.KCl B.NH4ClC.KHSO4D.K2HPO4
_________5.Aweakacidistitratedwithastrongbaseusingtheindicatorphenolphthaleintodetecttheendpoint.WhatistheapproximatepHatthetransitionpoint?
A.7.0 B.8.0C.9.0D.10.0
6.Explainyouranswertothequestionabove:
_________7.Whatvolumeof0.100MH2SO4isneededtotitrate25.0mLof0.200MNaOH?
A.12.5mL B.25.0mLC.50.0mLD.100.0mL
8.Showyourworkforthequestionabove:_________9.WhichofthefollowingtitrationsalwaysresultsinpH=7.0attheequivalencepoint?
A.Aweakacidistitratedwithaweakbase B.AweakacidistitratedwithastrongbaseC.AstrongacidistitratedwithaweakbaseD.Astrongacidistitratedwithastrongbase
10.Explainyouranswerthequestionabove:_________11.Whichofthefollowingpairsofchemicalscouldbeusedtomakeabuffersolution?
A.NH3andH2O B.HClandNaClC.NH3andNH4ClD.CH3COOHandHCl
_________12.Whenperformingatitrationexperiment,theindicatormustalwayshave
A.AdistinctcolourchangeatpH=7.0 B.TheabilitytochangefromcolourlesstopinkC.AtransitionpointthatisclosetotheequivalencepointD.Anequivalencepointthatisclosetothestoichiometricpoint
_________13.WhatisoneoftheKavaluesforthymolblue?
A.1.6x10-9B.2.0x10-7C.1.0x10-7D.6.0x10-2
14.Showyourworkforthequestionabove:_________15.WhichofthefollowingdescribesthenetionicequationforthehydrolysisofaNaNO2solution?
A.NaNO2⇋Na++NO2-B.NO2-+H2O⇋HNO2+OH-C.Na++2H2O⇋H3O++NaOHD.NaNO2+H2O⇋NaOH+HNO2
_________16.Whatdoachemicalindicatorandabuffersolutiontypicallybothcontain?
A.AstrongacidanditsconjugateacidB.AstrongacidanditsconjugatebaseC.AweakacidanditsconjugateacidD.Aweakacidanditsconjugatebase
_________17.WhatistheapproximatepHandKaatthetransitionpointforphenolred?
A. pH=6.6 Ka=3.0x10-7B. pH=7.3 Ka=1.0x10-14C. pH=7.3 Ka=5.0x10-8D. pH=8.0 Ka=1.0x10-8
Problems:1. CalculatethepHof0.60MNH4F.2. Youaregiventwobuffersolutions:
Buffer#1:1.0MNH3mixedwith1.0MNH4ClBuffer#2:0.1MNH3mixedwith0.1MNH4Cl.
a)WillthepHofthebuffersdifferfromeachother?Why?b)CalculatethepHofanundisturbedbuffersolution.c)Whichbuffersolutionwouldbemoreeffective?Explainyouranswer.
3. 40.0mLof0.10MNH3istitratedwith0.20MHClO4.Whatindicatorwouldbemostappropriateforthis
titration?Explainyouranswer.