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Weather ing Instruct ional Case: A ser ies of 5 student-centeredsc ience lessons
Lesson4
SuggestedTimeline45minutes
Materials
• 6effervescenttablets(suchasAlka-Seltzer®)
• clearplasticcup• thermometer• timer• wastebowl• disposablecoffeecups(forhotwater)• hotwater• ice• roomtemperaturewater• smallhammers(orothertooltocrushtablets)
Prep1. Studentsshouldhaveasystemof
howtotakenotesfromapresentation(Cornell,interactivenotebook,etc.)
2. MakecopiesoftheEffervescentAntacidWeathering
3. Preparetrays/binsofmaterialsforeachgroupandhaveatablesetupinanareawitheasyaccesstothehotwater,roomtemperaturewater,andice.
EffervescentAntacidWeathering
SummaryInthisinquiry-basedlesson,studentsinvestigatehowdifferentfactorsaffecttherateofchemicalweathering.Thedissolutionofcommoneffervescentantacidtabletsareusedasamodelforchemicalweathering.Duringthefirstpart,studentsrunfourteststodeterminehowtemperatureaffectstherateofdissolution.Theyaregiventhreedifferenttemperaturesofwater(hot,roomtemperature,andice)andthendecideonafourthtemperature,buildingtheirreasoningandinquiryskills.Aftertesting,studentscompleteaC-E-Rresponsebasedontheirresults.
Inparttwo,studentsengageinmoreinquirytodesigntwomoreteststomaketheeffervescentantacidtabletdissolveevenfaster.
Objective
• Toengagestudentsbygivingthemthefreedomtocreatedifferenttests
• Tocollectdatausingscientificinstruments• Touseevidencecollectedtoexplainhowtemperatureandotherfactorsaffecttherateofdissolution.
TeacherBackgroundKnowledgeThisactivityprimarilyinvestigateschemicalweatherandthefactorsthatmayaffecttherateofweathering.Therearetwotypesofweatheringprocesses:chemicalandphysicalweathering.Physicalweathering(alsoknownasmechanicalweathering)istheresultofphysicalforcesthatbreakrockintosmallerandsmallerpieceswithoutchangingtherock'smineralcomposition.Chemicalweatheringinvolvesthechemicaltransformationofmineralsandcommonlyresultsinthedissolutionofmineralsinarock.Generally,chemicalreactionsoccurmorerapidlyathighertemperatures.Thusitisclearthatchemicalweatheringofrocksandmineralsismoreintenseinwarmerenvironments(lowlatitudes)thanincolderenvironments(highlatitudes).Inaddition,chemicalweatheringisgenerallyenhancedinwetenvironments.Thephysicalweatheringofrocksincreasestherateofchemicalweatheringbyincreasingthesurfaceareaonwhichchemicalreactionsoccur.Thisisanalogoustothemorerapiddissolutionofgranulatedsugarinacupofcoffeerelativetoasinglelargerocksugarcrystal.
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Lesson4EffervescentAntacidWeathering
Standards12
NGSSPerformanceExpectations:ThislessonsupportsstudentsinprogressingtowardtheNGSSPerformanceExpectation.MS-ESS2-1.DevelopamodeltodescribethecyclingofEarth'smaterialsandtheflowofenergythatdrivesthisprocess.[ClarificationStatement:Emphasisisontheprocessesofmelting,crystallization,weathering,deformation,andsedimentation,whichacttogethertoformmineralsandrocksthroughthecyclingofEarth’smaterials.]MS-ESS2-2.ConstructanexplanationbasedonevidenceforhowgeoscienceprocesseshavechangedEarth'ssurfaceatvaryingtimeandspatialscales.[ClarificationStatement:EmphasisisonhowprocesseschangeEarth’ssurfaceattimeandspatialscalesthatcanbelarge(suchasslowplatemotionsortheupliftoflargemountainranges)orsmall(suchasrapidlandslidesormicroscopicgeochemicalreactions),andhowmanygeoscienceprocesses(suchasearthquakes,volcanoes,andmeteorimpacts)usuallybehavegraduallybutarepunctuatedbycatastrophicevents.Examplesofgeoscienceprocessesincludesurfaceweatheringanddepositionbythemovementsofwater,ice,andwind.Emphasisisongeoscienceprocessesthatshapelocalgeographicfeatures,whereappropriate.] AssessmentBoundaries:Assessmentislimitedtotheinteractionsoftwosystemsatatime.Inthislesson…ScienceandEngineeringPractices DisciplinaryCoreIdeas CrossCuttingConcepts
PlanningandCarryingOutInvestigationsStudentswillplananinvestigationthatanalyzestheeffectsoftemperatureondissolutionrates.Studentswillindividuallyandcollaborativelyconsiderthedifferentvariables.Studentswillhavetheopportunitytorevisetheirexperimentaldesigntotrytoincreasetheratesofdissolution.Quantitativeandqualitativedatawillbecollectedtoserveasevidenceforconstructingtheirexplanations.
ESS2.A:Earth’sMaterialsandSystemsTheplanet’ssystemsinteractoverscalesthatrangefrommicroscopictoglobalinsize,andtheyoperateoverfractionsofasecondtobillionsofyears.TheseinteractionshaveshapedEarth’shistoryandwilldetermineitsfuture.ESS2.C:TheRolesofWaterinEarth'sSurfaceProcessesWater’smovements—bothonthelandandunderground—causeweatheringanderosion,whichchangetheland’ssurfacefeaturesandcreateundergroundformations.
StabilityandChangeStudentsexaminechangesinonepartofasystemandrelateittohowchemicalweatheringoccursatdifferentratesdependingondifferentclimates.SystemandSystemModelsStudentscreateamodelofdifferentenvironmentsusingdifferenttemperaturerangesofhotwaterandthenobservehowtheeffervescentantacidtabletis“chemicallyweathered”.
Inthislesson…CCSSMathematics CCSSEnglish-LanguageArtsCCSS.MATH.CONTENT.6.RP.A.3Useratioandratereasoningtosolvereal-worldandmathematicalproblems,e.g.,byreasoningabouttablesofequivalentratios,tapediagrams,doublenumberlinediagrams,orequations.
CCSS.ELA-LITERACY.RI.6.7Integrateinformationpresentedindifferentmediaorformats(e.g.,visually,quantitatively)aswellasinwordstodevelopacoherentunderstandingofatopicorissue.
1NGSSLeadStates.2013.NextGenerationScienceStandards:ForStates,ByStates.Washington,D.C.:TheNationalAcademiesPress.2NationalGovernorsAssociationCenterforBestPractices,CouncilofChiefStateSchoolOfficersTitle:CommonCoreStateStandards(insertspecificcontentareaifyouareusingonlyone)Publisher:NationalGovernorsAssociationCenterforBestPractices,CouncilofChiefStateSchoolOfficers,WashingtonD.C.CopyrightDate:2010
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Lesson4EffervescentAntacidWeathering
PriorKnowledgeIngrades3-5,studentslearnedthatwater,ice,wind,organisms,andgravitybreakrocks,soils,andsedimentsintosmallerpiecesandmovethemaround.StudentshavealsolearnedthatmostofEarth’swaterisintheoceanandmuchoftheEarth’sfreshwaterisinglaciersorunderground.Inthepreviouslessons,studentshavelearnedaboutmechanicalweatheringandtheroleofweatheringanderosionwhenformingmountainsandlandscapes.Studentshavealsolearnedaboutthedifferenttypesofweatheringandhadasmallintroductiontochemicalweatheringusingaflavoredhardcandy.
LessonPART11. Posethefollowingquestionstotheclass:“Willwatertemperatureaffecthowfastaneffervescenttable
willdissolve?”and“Howdoesthetemperatureofwateraffecthowfastaneffervescenttabletwilldissolve?”
2. Instructstudentstoselecttheirpredictionontheirworksheetandexplaintheirthinking.3. Dividestudentsintogroupsof4.4. Explaintherulesforcreatingthetestingproceduresforpartoneandpointoutwherematerialsare.5. Checkwithgroupsastheymaketheirprocedurestomakesuretheyaregatheringdatathatanswersthe
presentedquestion.Aftercheckingwithgroups,allowthemtogetmaterialsandperformthe4tests.6. Instructstudentstocarefullywatchforwhenthetabletdisappearsandnotwhenthewaterstopsfizzing.
Itisimportantthatstudentsmeasuretheamountoftimethatittakesforthetablettodissolvethesamewayeachtimeinordertogetgoodresults.
7. Studentswillfindthatthedissolutionrateisclearlyafunctionoftemperaturewherethewarmerthewater,theshorterthetimeittakesforthetablettodissolve.
8. Asgroupsofstudentsfinisheachtesttheyshouldrecordtheirdataandobservations,poureachcompletedtestintotheirwastebowl,thenproceedwiththenexttest.
9. Afterstudentshavefinishedthefourtests,havethemanswertheanalysisquestion.PART210. Instructgroupsthathavefinishedtestingtobrainstormadditionalwaystomaketheeffervescenttablets
dissolveevenfaster.11. Oncethesegroupshavediscussedmoreideas,givethem2moretabletsandhavethemcompletetwo
moretests12. Inthebestcase,studentswillwanttobreakupthetablettoseeifthatchangesthedissolutionrate.The
teachermayneedtoguidestudentstothisexperiment.Thetabletmaybecrushedbygentlytappingitwithahammerwhilethetabletisinsidethepacketorinasmallplasticbag(orwrappedinpaper).
13. Ideally,studentswillperformacontrolledexperimentwhereonetabletiswhole,thesecondiscrushedandthetemperatureofthewateristhesameinbothtrials.Inthisway,studentscancomparetheeffectofcrushingthetablet(withwatertemperaturebeingequal).
14. Studentswillfindthatacrushedtabletwilldissolvemorerapidly(almostinstantaneously)thatawholetabletduetotheincreaseinthesurfaceareainthecrushedtablet.
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Lesson4EffervescentAntacidWeathering
PotentialPitfallsStudentsareaskedtocreate4testsinpart1buttheyareonlygiventhreedifferenttypesofwater(hot,roomtemperature,andice).Thisisdonetopushstudentstothinkaboutdifferentwaystheycantesttheirquestion.Remindstudentsthattemperatureisacontinuumandtheyneedtocreateatemperatureofwatertheyhaven’ttestedbefore.
Inordertogetgoodconsistentresults,studentsmustagreetowhentheywillstoptimingthedissolutionofthetablet.Thetabletwilldisappearbeforethefizzingofthesolutionends.Studentsmustcloselyobservethetabletandmeasurethetimeittakesforittodisappear.
Aftercreatingandobservingthismodelactivity,studentsmayconcludethatchemicalweatheringisarapidprocesssincethetabletsdissolvesoquickly.Itshouldbereinforcedtostudentsthatthetabletsareonlyamodelfortheweatheringofrockandthatrealrocksareaffectedbychemicalreactionsatamuchslowerrate.Makesurethatstudentsunderstandtherelativetimeframesforgeologicchangeastheyrelatetoweatheringofrock.
Ifsomegroupsfinishearly,theycanusetheextratimetobrainstormabouthowtotestotherfactorsthatwillaffecttheamountoftimeittakesforatablettodissolve.
WeatheringofstatueinDresden,GermanySource:WikimediaCommonsUserSlick