weathering 4 lesson - earth science lesson.pdf · weathering) is the result of physical forces that...

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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