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__tterinYourWorld
4.1Notes__tterisany__terialthatoccupiesspa__andhas__ss.__tterincludesallsolidsliquidsandgases.Theseformsof__tterh__edifferentcharacteristics.Thecharacteristicsthatareusedtodescribe__tterarecalledproperties.Every__terialhasitsownsetofproperties.Undernor__lconditionswaterfreezesat0oCandboilsat100oCitisalsoclearcolourlessodourlessliquid.Wheneveryouseea__terialthathasmorethanonesetofpropertiesyouknowthatitisamixture.Amixturecontainsmorethanonekindof__tterAmixturecontainsmorethanonekindof__ttercombinedinsuchawaythateachkeepsitsownproperties.Mixturesthatare__deupofpartsthatcanbeseenarecalledheterogeneous.Heterogeneousmeans__deupofpartsormixed.__terialsthath__eonlyonesetofpropertiesarecalledhomogeneous.Homogeneousmeansthateverypartofthe__terialisthesame.Anexampleofheterogeneous__terialisonpage103inthetextbook.__mentorconcreteisheterogeneous.CheckYourUnderstanding
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11.Somepropertiesofwaterareclearcolourlessordourlessfreezesat0oCboilsat100oCdissolves__nysubstan__s.SomepropertiesforglassaretransparentharddurablebreakseasilyinflexibleSomepropertiesforsteelareopaquehe__ystrongwillrustandcorrodeinflexible.
2.Youcannotdistinguishbetweenthedifferentcomponentsinahomogeneousmixturesothemixtureappearsthesameallover.Ahetergeneousmixturedoesnotappearthesamealloverandthedifferentcomponentsarevisible.
3.answerswillvary
4.aThewaterinoneriverwillh__eonesetofproperties.bRiverwaterisheterogeneous.Thebrowncolourisriverwaterindicatesthepresen__ofdirtparticles.
5.studentsanswerswillvarybuttheyshouldrealizethatmost__terialsareheterogeneous
4.2NotesWhatisamixtureAnythingwithtwodistinctsetsofpropertiesmustbeamixtureofatleasttwo__terials.Whenamixturesdifferentpartscanbeidentifiedthiseasilythemixtureisusuallycalledamechanicalmixture.Homogeneousmixturesiscalledasolution.Solutionsareeverywhere.TwothirdsofEarthiscoveredwithaliquidsolution-thesaltywateroftheo__ans.Earthissurroundedbyagasslutionthatwecallair-ahomogeneousmixtureofoxygennitrogenandothergases.Thereareevensolidsolutions.Mixturesareabsolutelyeverywhereyoulook.Mixturesaretheformformostthingsinnature.Rocksairortheo__antheyarejustaboutanythingyoufind.Theyaresubstan__sheldtogetherbyphysicalfor__snotchemical.Thatstatementmeanstheindividualmoleculesenjoybeingneareachotherbuttheirfundamentalchemicalstructuredoesnotchangewhentheyenterthemixture.Whenyouseedistilledwateritsapuresubstan__.Thatfactmeansthattherearejustwatermoleculesintheliquid.Amixturewouldbeaglassofwaterwithotherthingsdissolvedinside__ybesalt.Eachofthesubstan__sinthatglassofwaterkeepstheoriginalchemicalproperties.Soifyouh__esomedissolvedsubstan__syoucanboiloffthewaterandstillh__ethosedissolvedsubstan__sleftover.Becauseittakesveryhightemperaturestoboilsaltthesaltisleftinthecontainer.CheckYourUnderstanding
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21.Youneedtwopropertiestoobserveaheterogeneousmixture.
2.AAsolutionisahomogeneousmixture.Asoluteisdissolvedinasolvent.BForamixturetobeasolutionthecombinationof__terialsneedstobethesamethroughout.Thedifferentbitsofthe__terialscannotbeseen.
3.Poursomeoftheliquidintoacuptoadepthofabout1cm.Le__ethecupuncovered.Afterafewdayscheckthecup.Theliquidshouldh__eevaporated.Ifcrystalsarepresentthentheliquidwasprobablyamixtureofsaltandwater.Otherwiseitwasmostlikelypurewater.
4.aO__anwaterhasallthepropertiesofwaterinadditiontothepropertiesofsalt.Theindividualbitsofwaterareexactlythesamethroughoutthemixture.
4.bO__anwaterhasallthepropertiesofsaltinadditiontothepropertiesofwater.Thebitsofsaltarethesamethroughoutthemixturebuttheyarenotvisible.
5.aIfthebitsandblobswerenotpartofthemixturebutcamefromsomewhereelsethenthemixturecouldbehomogeneous.bYouwouldneedeviden__thatthebitsandblobsarepartofthemixture.Iftheywerepartofthemixturethenthemixturewouldbeheterogeneousandyourpartnerwouldbecorrect.
6.Acloudishomogeneoussin__thewaterdropletsareevenlymixedthroughoutanddifferentkindsofparticlesarenotvisible.
7.Thefoamontopofthew__esistheresultofbubblesofairbeingmixedwiththewaterasthew__esbreakalongtheshoreline.CheckYourUnderstanding
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31.All__tteris__deupoftinyparticles.Eachpuresubstan__hasitsownkindofparticle.
2.Puresubstan__sh__eonekindofparticle.Mixturesh__eatleasttwokindsofparticles.
3.Iftheparticlesareextremely__allit__ybedifficultto____thedifferen__betweenapuresubstan__andamixture.
4.aStudentsdiagramsshouldindicatethepresen__ofbothalcoholandiodineparticles;howeverwiththeiodineparticlesevenlydistributedamongthealcoholparticles.bTheparticlesofiodineh__eonesetofpropertiesandtheyareallthesame.Theparticlesofalcoholh__eadifferentsetofproperties.Whenthetwoaremixedtheresultingsolutionhasbothsetsofproperties.
4.cThepropertiesbecameblendedbecausetheiodineparticlesareevenlyscatteredamongthealcoholparticles.Chapter4Review
2.aBothmixturesandsolutionsh__emorethanonetypeof__tter.bAsolutionishomogeneousbecausetheparticlesareevenlymixedandithasthesamesetofpropertiesthroughout.cApuresubstan__mustbehomogeneous.dIfamixturehasmorethanonesetofpropertiesitisheterogeneous.ePropertieshelptodistinguishdifferentparticlesinamechanicalmixture.fPuresubstan__sh__eonlyonekindofparticle.
3.aExamplesof__terialsthataredefinitelyheterogeneousareconcreteanoilspillinwatermineralrocksItaliansaladdressingandasand-and-watermixture.3bExamplesof__terialsthataredefinitelyhomogeneousarecoffeeapplejui__vinegarametalalloyandamixtureofalcoholandwater.cMilkappearshomogeneousbutitisinfactheterogeneous.
4.Amixtureisa__terialthathasmorethanonekindof__tterandthereforemorethanonesetofproperties.Examplesareorangejui__handcreamandbuttermilk.Apuresubstan__isa__terialthatis__deupofonlyonekindofparticlewiththesamepropertiesthroughout.Examplesaregoldalcoholdistilledwaterandoxygen.
5.Atheorythatexplainsthe__ke-upof__tteristheparticletheoryof__tter.Thetwo__inideasofthistheoryarethese:1All__tteris__deupoftinyparticles.2Eachpuresubstan__hasitsownkindofparticledifferentfromtheparticlesofotherpuresubstan__s.6aDiagramCrepresentsahomogeneousmixture.bDiagramArepresentsamechanicalmixture.cDiagramBrepresentsapuresubstan__.dDiagramDrepresentsadifferentpuresubstan__.
8.aThemodelshouldshowregularlyspa__dstyro-peanutsofonecolourforeachpuresubstan__.bThemodelshouldshowacombinationoftwocoloursofpeanutswithanunevendistributionforHeterogeneous.cThemodelshouldshowacombinationoftwocoloursofpeanutsevenlydistributedthroughoutforHomogeneous.
9.aInordertoseparateasolutionallowthemixturetostandforaperiodoftimetoallowtheoilandwatertoseparateintolayers.bSeparatethetwo__terialsaccordingtocolourlustreorshape.Youcouldalsousea__gnettoseparatethepaperclips.cAddwatertothemixtureandstir.Thesugarwilldissolveandthesawdustwillfloattothesu_____.Useascreenorasievetoremovethesawdust.Allowthewatertoevaporatetole__ethesugarbehindatthebottomofthecontainer.
11.aAsoftdrinkisahomogenousmixturesin__theparticlesappeartobethesamethroughoutandareevenlymixed.bWhenthesoftdrinkispouredintoaglassitisheterogeneous.Thereiseviden__ofatleasttwodifferentkindsof__tter.Particlesbubblescanbeseenandtheyareunevenlydistributedinthemixture.
12.Theparticlesinacrystalofsugarandinasugarcubearethesame.Sin__theybothh__ethesameparticlestheyh__ethesamepropertiesaswell.
13.Ifthemixtureisunevenitisheterogeneous.Ifthe__terialisthesamethroughoutandtheparticlesareevenlymixeditishomogeneous.Pottingsoilandpesticidepelletsareheterogeneous.Fertilizerishomogeneous.
14.Anexaminationofpottingsoileasilyrevealsthemixturesdifferent__terialswithvaryingsizesandshapes.Thehandlenswouldbeneededhoweverforbandctodetermineifthereareanybitswithdifferentproperties.
15.Amixtureofsaltandwatercontainsparticlesfoboth__terialsandthereforehastwosetsofproperties.Itisahomogeneousmixturebecausethesaltparticlesareevenlyscatteredthroughoutthewaterparticlesandtheyarenotvisible
16.Waternor__llycontainssomedissolvedmineralsandgaseswhichgiveitmostofitstaste.Waterfromdifferentsour__s__ycontaindifferentkindsofdifferentamountsofmineralsandgases.ReviewfortheTestGroupDiscussionQuestionsInstructions:Everyoneinthegroupistotakeonequestionandfindthebestpossibleanswertosharewiththegroup.Questions:
1.ListthetwopointtotheParticleTheoryof__tterthatweh__elearnedanddiscussinyourownwords._____________________________________________________
2.Whatisamechanicalmixture_____________________________________________________
3.Howcanweseparateamechanicalmixture_____________________________________________________
4.Usetheparticletheoryof__ttertoexplainhowasolutionofsugarandwaterisformed______________________________________________________
5.List3examplesofamechanicalmixture._________________________________________________。