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1 2 3 4 5 009 08 07 06 05 04 CHEMISTRY SMALL-SCALE LABORATORY MANUAL Contents

To the Student ...... iv Small-Scale Laboratory Techniques ...... v Safety in the Laboratory ...... vi Safety Symbols ...... vii

Laboratory Activities 1 Small-Scale Laboratory Techniques ...... 1 2 Comparing the Density of Metals ...... 5 3 Separation of Aspirin ...... 9 4 Periodicity and the Properties of Elements ...... 13 5 Properties of Transition Metals ...... 17 6 Modeling Molecular Shapes ...... 21 7 Solutions and Precipitates ...... 25 8 Determining Avogadro’s Number ...... 29 9 Measuring Boiling Point ...... 33 10 Relating Gas Pressure and Gas Volume ...... 37 11 Effect of Temperature on Solubility ...... 41 12 Specific Heat of Metals ...... 45 13 Energy Changes in Chemical and Physical Processes ...... 49 14 Determining Reaction Orders ...... 53 15 Observing Equilibrium ...... 57 16 Exploring Chemical Equilibrium ...... 61 17 Comparing the Strengths of Acids ...... 65 18 Testing the Acidity of Aspirin ...... 69 19 Reduction of Manganese ...... 73 20 Plants Produce Oxygen ...... 77 Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

Chemistry Small-Scale Laboratory Manual iii iv ¥ ¥ ¥ ¥ ¥ ¥ Organization of Activities Chemistry Small-ScaleLaboratory Manual the primarymeansthatchemistsusetolearnmoreaboutmatter. The activitiesinthe a processforfindingoutmoreaboutmatteranditschanges.Laboratoryactivitiesare gathered byscientistsaboutmatter. Butchemistryisnotjustinformation.Italso work inchemistry, youwilllearnagreatdealoftheinformationthathasbeen Chemistry isthescienceofmatter, itsproperties,andchanges.Inyourclassroom are thesameasthoseusedbyprofessionalchemistsandallotherscientists. conclusions basedonthosedataandyourknowledgeofchemistry. These processes eses, measureandrecorddataobservations,analyzethosedata,draw ¥ ¥ must observethesamesafetyprecautionsasforanychemistryexperiment. observations thatyouwoulduseinlarge-scale laboratoryactivities.Likewise,you small-scale chemistry, youshouldusethesamecareinobtainingdataandmaking tubes. You alsouse smallamountofchemicalsinreactions.Still,whenworkingwith use plasticpipettesandmicroplatesinsteadoflarge glassbeakers,flasks,andtest in laboratorytechniques ¥ ¥ ¥ To theStudent provides abackgrounddiscussionabouttheproblemyouwillstudyinactivity. concepts neededtocompletetheactivitysuccessfully. happened. conclusion basedonwhat you actuallyobserved,notwhat order toreachanexperimental result. You are alsoaskedtoformascientific sions. Itprovidesquestionstoaidyouininterpreting data andobservationsin perform thecalculationsnecessaryforyoutoanalyze yourdataandreachconclu- Some activitieshave activity andsometimesoffer hintstohelpyoubesuccessfulinthelaboratory. additional conclusions orresearchaquestion relatedtotheactivity. have learnedintheactivity tootherreal-lifesituations. You maybeaskedtomake symbols mean. in thelaboratory. Beforebeginninganyactivity, refertopageviiseewhatthese ized wayasyoudotheactivity. collecting yourlaboratorydata. Always recorddataandobservationsinanorgan- Real-World Chemistry Analyze andConclude Data andObservations Hypothesis Procedure Pre-Lab Safety Precautions Materials Objectives Problem Introduction hazardous substancesortechniques. esis forthisactivity. activity. the investigation.Recheckthislistwhenyouhavefinishedactivity. Chemistry Small-ScaleLaboratory Manual The questionsinthissectioncheckyourknowledgeofimportant The problemtobestudiedinthisactivityisclearlystated. ” The materialslistshowstheapparatusyouneedtohaveonhandfor An opportunitytoanalyzepossibleerrors intheactivityisalsogiven. The numberedstepsoftheproceduretellyouhowtocarryout The objectivesarestatementsofwhatyoushouldaccomplishbydoing This sectionprovidesanopportunityforyoutowrite downahypoth- Following thetitleandnumberofeachactivity, anintroduction Safety symbolsandstatementswarnyouofpotentialhazards CAUTION — The questionsinthissection askyoutoapplywhat The Analyze and Concludesectionshowsyouhowto This sectionpresentsasuggestedtableorformfor small-scale chemistry. Insmall-scalechemistry, youoften statements intheproceduretoalertyou require thatyouformandtesthypoth- activities usethelatestdevelopment Chemistry Small-Scale LaboratoryManual “ should have

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. chemistry equipmentcanbe washedwithdistilledwaterforreuse. Chemistry Small-Scale LaboratoryManual Discard allsubstancesaccording toyourteacher Waste Disposal of thechemicalreactionsthat occurineachwell. Use MicroplateDataFormstowritedownthechemicals usedandtorecordyourobservations color changesandprecipitateformationswithease. micropipettes. The whitepaperbackgroundprovidedbythetemplateallowsyou to observe and columnislabeledtohelpguideyouwithyourplacement ofchemicalsfromthe 96-well microplate. The templateismarkedwiththecorrectnumberofwells,and eachrow To helpyouwithyourobservations,placetheMicroplate Template beneathyour24-wellor ever youcarryoutanactivitythatrequiresthem. Your teachercanprovideyouwith Microplate Templates andMicroplateDataFormswhen- The Microplate Template andMicroplate DataForm way glassdoes. reagents. The plasticinsidethe pipetteisnon-wettinganddoesnotholdwaterorsolutionsthe been pre-stretchedatthefactory. Itisnotnecessarytostretchamicrotippipette. deliver atinydropofreagent. You mayalsouseapipettecalledmicrotippipette,whichhas heating intoathintube.Ifthestemisstretchedandthencutwithscissors,smalltipwill The mostusefulpropertyofthepipetteisfactthatstemcanbestretchedwithout Small-scale chemistryusesapipettemadeofformplasticthatissoftandveryflexible. The PlasticPipette 24 larger wells. of testtubes,flasks,andbeakers.Somemicroplateshave96wells;other rows (runningacross)andcolumnsupdown). These wellsareusedinstead The firstisasturdyplastictraycalledmicroplate. The trayhasshallowwellsarrangedin The Microplate more experimentsandhaveasaferenvironmentinwhichtowork. used inmicrochemistrytechniques.Byusingsmall-scalechemistry, youwillbeabletodo must beheated,hotwaterwillprovidetheneededheat.Openflamesorburnersareseldom The hazardsofglasshavebeenminimizedbytheuseplasticlabware.Ifachemicalreaction Small-scale chemistryusessmalleramountsofchemicalsthandoothermethods. Small-Scale Laboratory Techniques The pipettecanbeusedoverandagainsimplybyrinsingthestembulbbetween Small-scale chemistryusestwobasictools. CHEMISTRY SMALL-SCALELABORATORY MANUAL Cutting astretchedpipette Pipette ’ s instructions. All plasticsmall-scale Cut v vi 12. 11. 10. rules tohelpguideyouinprotectingyourselfandothersfrominjuryalaboratory. printed inthismanualandthosegiventoyoubyyourteacher. The followingaresomesafety caused bycarelessness,butyoucanhelppreventthemcloselyfollowingtheinstructions for yourownpersonalsafetyandthatofpeopleworkingnearyou. Accidents areusually The chemistrylaboratoryisaplacetoexperimentandlearn. You mustassumeresponsibility Safety intheLaboratory 9. 8. 7. 6. 5. 4. 3. 2. 1. oratory. Work onlywhenyourteacherispresent. unless specificallyinstructed todoso.Usetest Do Do Handle chemicalscarefully. damaged equipmentimmediatelytoyourteacher. Report anyaccident,injury, incorrectprocedure,or for you. Know howtousethesafetyequipmentprovided shower, eyewash,fireblanket,andfirst-aidkit. Know thelocationoffireextinguisher, safety feet orsandalsarenotpermittedinthelab. Wear shoesthat coverthefeetatalltimes.Bare chemical apparatus. either theclothingorjewelrycouldcatchon clothing. The looseclothingmaycatchfireand Avoid wearingdanglingjewelryorloose,draping possibility ofitcatchingfire. Long hairshouldbetiedbacktoreducethe are difficult toremoveinanemergency. if gogglesareworn.Lensescanabsorbvaporsand Contact lensesshouldnotbeworninthelab,even skin. cause irritationsorcanbeabsorbedthroughthe should bewornwheneveryouusechemicalsthat worn wheneveryouworkinthelab.Gloves Safety gogglesandalaboratoryapronmustbe Study yourlabactivity teacher work. Donotperformactivitieswithoutyour The chemistrylaboratoryisaplaceforserious your teacherforhelp. lab. Ifyouareindoubtaboutanyprocedures,ask and whenyouputthebottle back. container, whenthecontainerisin yourhand, the labelsthreetimes:beforeyoupickup all bottles not not ’ return unusedchemicalstoreagent bottles. take reagentbottlestoyour work area s permission. before removing thecontents. CHEMISTRY SMALL-SCALELABORATORY MANUAL Never before Check thelabelsof work aloneinthelab- you cometothe Read 14. 13. 24. 23. 22. 21. 20. 19. 18. 17. 16. 15. Never small amountofthechemicalintoabeaker. Do chemicals directlyonthepanofbalance. Keep thebalanceareaclean.Neverweigh solutions. Know thecorrectprocedureforpreparingacid teacher. products ofreactionsonlyasdirectedbyyour Dispose ofbrokenglass,unusedchemicals,and looks thesameascoolglass. handling hotapparatusorglassware.Hotglass Use cautionandtheproperequipmentwhen of atesttube. person oryourself.Neverlookdownthemouth not topointthemouthoftubeatanother When heatingasubstanceintesttube,becareful such materialsarepresent. direction ofyourteacher. Usethefumehoodwhen Handle toxicandcombustiblegasesonlyunderthe flames. (Alcoholandacetonearecombustible.) Keep combustiblematerialsawayfromopen the natureofspill. ties ofwater. Immediatelyinformyourteacherof skin, flushtheareaimmediatelywithlarge quanti- If chemicalscomeintocontactwithyoureyesor than todisposeofexcess. Take onlysmallamounts.Itiseasiertogetmore tubes, paper, orbeakerstoobtainyourchemicals. prohibited inthelaboratory. Eating, drinking,chewinggum,andsmokingare any chemicalsintoapipettewithyourmouth. the gasandwaterareturned off. Wash your hands your equipment.Clean workarea.Makesure After completinganactivity, cleanandputaway pipettes withalaboratoryburner. Do not not taste anychemicalsubstance. insert droppersintoreagentbottles.Poura heat graduatedcylinders,burettes, or Chemistry Small-Scale LaboratoryManual Always add theacidslowlytowater Never draw .

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual SAFETY SYMBOLS displays asymbol. the textbookandareexplainedbelow. Besureyouunderstandeachsymbolbeforebeginanactivitythat Chemistry usessafetysymbolstoalertyoupossiblelaboratorydangers. These symbolsareprovidedin TEMPERATURE BIOLOGICAL ELECTRICAL CHEMICAL DISPOSAL EXTREME IRRITANT activities. science observing or performing one any- by times all at worn be should tion protec- eye Proper Eye Safety OBJECT FLAME SHARP TOXIC FUME OPEN CHEMISTRY SMALL-SCALELABORATORY MANUAL loose clothing, or hair or clothing, loose chemicals, flammable ignite may flame Open fumes from tract respiratory to danger Possible skin slice or puncture easily can that ware glass- or tools of Use hot too or cold too being by skin burn can that Objects humans to harmful be might that materials biological other or Organisms followed. be to need cedures pro- disposal Special inhaled, or swallowed or inhaled, touched, if poisonous be may Substance rials mate- other and tissue destroy and with react can that Chemicals tract respiratory the of membranes mucous or skin the irritate can that Substances burn or shock electrical from danger Possible HAZARD clothing. burn or stain could substances when appears symbol This Protection Clothing ganate, hair,ganate, clothing perman- potassium kerosene, alcohol, balls sulfur,heated moth remover,polish nail acetone, ammonia, glass broken probes, dissecting tools, pointed scalpels, pins, blades, razor nitrogen liquid ice, dry plates, hot liquids, boiling materials plant tissues, unpreserved blood, fungi, bacteria, organisms living chemicals, certain poinsettia plant parts plant poinsettia iodine, compounds, mercury,metal many hydroxide sodium ammonia, as such bases acid; hydrochloric acid, sulfuric as such acids peroxide; hydrogen as such bleaches ganate perman- potassium fiberglass, wool, steel balls, moth pollen, wires exposed circuits, short spills, liquid grounding, improper EXAMPLES materials are used. are materials radioactive when appears symbol This Radioactivity directly. Wear a mask. directly.a Wear fumes smell Never ventilation. good is there sure Make tool. the of use for guidelines follow and behavior sense common- Practice handling. when protection proper Use gloves. or mask Wear materials. these with contact skin Avoid can. trash or sink the in materials these of dispose not Do equipment. safety fire of locations of aware Be chemicals. flammable using when flames open Avoid clothing. loose wearing hair.back TieAvoid instructions. teacher’syour Follow apron. an and gloves, goggles, Wear materials. these handling when care extra Practice gloves. and mask dust Wear apparatus. and wires of condition teacher.with Check setup Double-check PRECAUTION applicable. if equipment safety immediately.fire Use teacher your Notify immediately. teacher your notify and area foul Leave aid. first for teacher your to Go aid. first for teacher your to Go thoroughly.hands Wash material. with contact suspect you if teacher your Notify teacher. your by directed as wastes of Dispose first aid. first for teacher your to Go use. after thoroughly hands wash Always teacher. your notify and water with area affected the flush Immediately aid. first for teacher your to Go immediately. teacher your Notify problems. electrical fix to attempt not Do goggles. beforeremoving water and hands withsoap wash After thelab, Handwashing REMEDY vii

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. N Techniques Small-Scale Laboratory Chemistry Small-Scale LaboratoryManual 1. Mass Measuring Part A: Procedure 3. 2. 1. Pre-Lab Safety Precautions of candyinwater? to makeadilutesolution What techniquesareused Problem Name measurements varywiththetypeofinformationthatisbeingcollected. produced. Theequipmentandtechniquesusedtomakescientific substance ispresent,whatitstemperatureis,orhowquicklyitwas information aboutthephenomenatheystudy, suchashowmuchofa Techniques Small-Scale Laboratory the pointerswingsfreelyalong thescale. as theywillgo,shownin Slide alltheridersonbalanceasfartoleft centimeters? How manymillilitersarein1liter?In20cubic What quantityismeasuredinmilliliters? What istheSIbaseunitformass? LAB some sort.Measurementsallowchemiststocollectquantitative early allexperimentsinchemistryinvolvemakingmeasurementsof 1 LABORATORY MANUAL CHEMISTRY SMALL-SCALE Figure A. • Alwayswearsafetygogglesandalabapron. • • • Objectives • piece ofcandy. Use Dissolve small amountofwater. Measure Measure water solution. dilutions ofthecandy- microplate tomakeserial water. a pipetteand Check that the candyin the massofa the volumeofa 2. below zeroareequal. adjustment screwuntiltheswingsaboveand the zeromarkonscale.Ifitdoesnot,turn should swinganequaldistanceaboveandbelow With nothingonthebalancepan,pointer Adjustment Balance pan screw aeClass Date balance candy 24-well microplate 25-mL graduated 100-mL beaker Materials cylinder Riders sheet ofwhite thin-stem pipette spatula mortar andpestle Pointer paper Scale Figure A 1 2 1. MakingaSolution Part C: 2. 1. Measuring Volume Part B: Figure B 6. 5. 4. 3. Name LAB cylinder hasacurvedsurface,called and pestle,asshownin Grind thecandyintosmall pieceswiththemortar Data Table1. in Record thevolumetonearest0.1mL that linesupwiththebottomofmeniscus. by theclosestmarkingonsideofcylinder The volumeofwaterinthecylinderismeasured cylinder. As ofwaterintothegraduated Pour about20mL candy tothenearest0.1gin zero mark.Recordthemassofbeakerplus swings anequaldistanceaboveandbelowthe Reposition theridersuntilpointeragain Place onepieceofcandyinthebeaker. the beakertonearest0.1gin indicated onthebeamriders.Recordmassof To findthemassofbeaker, addthemasses each riderrestsinanotch. zero mark.Ifthebeamsarenotched,makesure swings anequaldistanceaboveandbelowthe move theriderstorightuntilpointeragain Beginning withthelargest rideronthetopbeam, that thepointermovestotopofscale. Gently setthebeakeronbalancepan.Notice beaker. ula toscrapethegroundcandy backintothe be reducedtoafinepowder.) Usethespat- NOT markings. will needtoestimatethedistancebetweentwo up exactlywithamarkingonthecylinder, you meniscus ateyelevel.Unlessthispositionlines To takeavolumereading,viewthebottom ofthe Meniscus 1 Figure B 15 20 25 CHEMISTRY SMALL-SCALELABORATORY MANUAL shows, thewaterin Figure C. Data Table1. Data Table1. (Candy should meniscus . Figure C Figure D 2. 3. 2. 1. MakingSerialDilutions Part D: 3. Never placethepipette inyour mouth. beaker. dissolves inthewater. Pourthissolutionintothe Grind theremainingcandyinmortaruntilit water fromthegraduatedcylinderintomortar. If anycandyremainsinthemortar, poursome contains adilutedcandy-watersolution. the graduatedcylindertowellB2. Well B2now well B1toB2. Add 9dropsofwaterfrom Transfer 1dropofthecandy-watersolutionfrom well B1. Place 10dropsofthecandy-watersolutionin Notice thatthiswellislabeled A1. well ofthemicroplate,asshownin pipette toplace10dropsofwaterinthetopleft Fill thegraduatedcylinderwithwater. Usethe dissolved. the beakeruntilallofpiecescandyare Add therestofwatertobeaker. Swirl aeClass Date Chemistry Small-Scale LaboratoryManual CAUTION: Figure D.

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 4. 3. 2. 1. Analyze andConclude 1. Cleanup andDisposal 6. 5. 4. Name Real-World Chemistry the dilutedsolutionisammonia? (Hint:1tablespoon quart ofwater. Iftheundilutedsolutioncontains 10percentammonia,whatof can prepareadilutedsolution bymixing1tablespoonofammoniasolutionwith 1 Ammonia solutionisahousehold cleanerwithmanyuses. To cleanwindows,you LAB undiluted candy-watersolution.) solution inwellB2.(Hint:Rememberthatyouadded9dropsofwaterto1dropthe candy-water solutioninwellB1.(Hint: The answershouldhaveunitsofg/mL.) Measuring andUsingNumbers Thinking Critically Measuring andUsingNumbers Measuring andUsingNumbers to zero. condition asyoufounditandallridersareset Make sureyourbalanceisleftinthesame appears completelycolorless. Repeat step5untilthemostdilutesolution solution tothatoftheothers. water tothatwell.Comparethecolorofnew tion tothenextwellinrowB. Add 9dropsof Transfer 1dropofthedilutedcandy-watersolu- wells A1, B1,andB2. microplate. Comparethecolorofcontents Place asheetofwhitepaperbeneaththe dilute solutionyoumade(theonethatappearedcompletely colorless)? beaker fromthemassof 1 CHEMISTRY SMALL-SCALELABORATORY MANUAL Calculate theconcentrationofcandyindilutedcandy-water What wastheconcentrationofcandyinmost To findthemassofcandy, subtractthemassof Calculate theconcentrationofcandyin candy. Record theresultin Data andObservations 4. 3. 2. 15 mL,and1quart Volume of water(mL) Mass ofcandy(g) Mass ofbeaker+candy(g) Mass ofbeaker(g) detergent beforeyouleavethelab. Wash yourhandsthoroughlywithsoapor Dispose ofthecandy-watersolutionsinsink. Return alllabequipmenttoitsproperplace. aeClass Date Data Table1. Data Table 1 0.95 L) 3

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. D Comparing theDensityofMetals Chemistry Small-Scale LaboratoryManual 5. 4. 3. 2. 1. Pre-Lab Safety Precautions densities? metals bycalculatingtheir Can youidentifyunknown Problem Name important clueabouttheidentityofmaterial. the massandvolumeofasamplematerial,youcanobtainan defined astheratioofamaterial often usedtoidentifyunknownmaterialsisdensity. Densityis Comparing theDensityofMetals mass of50.0kg. What isthevolumeofbar? anda metalbarhasadensity of19.3g/mL A metal X? a volumeof12.1mL. What isthedensityof sampleofmetalXhasamass85.6gand A units? Is densitymeasuredinbaseunitsorderived derived units. Explain thedifference betweenbaseunitsand are theunitsfordensity? What istheformulatocalculatedensity? What LAB because theyhavedifferent properties.Onepropertythatis ifferent materialscanbedistinguishedfromoneanother 2 LABORATORY MANUAL CHEMISTRY SMALL-SCALE • • • • • Objectives measurements. each samplefromthese sample. metals. densities ofspecific densities withknown samples. volume offourmetal Identify Compare Calculate Measure Always wearsafetygogglesandalabapron. ’ s masstoitsvolume.Bymeasuring each metal the massand the calculated the densityof 3. 2. 1. Procedure Record thevolumeofwater tothenearest0.1mL. of thecylinderwithyourfingertoremovethem. there areairbubblesinthewater, taptheoutside Fill thegraduatedcylinderhalffullofwater. If Data Table1. ple tothenearest0.01g.Recordmassin Use thebalancetomeasuremassofsam- Record theletterofsamplein Select ametalsamplefromthematerialstable. aeClass Date paper towel water 50-mL graduated balance metal samples Materials CRC Handbookof cylinder Physics Chemistry and (optional) Data Table1. 5 6 1. Analyze andConclude 2. 1. Data andObservations 3. 2. 1. Cleanup andDisposal 5. 4. Name apeMs g water(mL) Mass(g) Sample LAB Acquiring and Analyzing Information To calculatethedensityofeachmetalsampleandrecordresultsin water To findthevolumeofeachmetalsample,subtractwaterfrom directed byyourteacher. Return alllabequipmenttoitsproperplace,as tion asyoufoundit. Make sureyourbalanceisleftinthesamecondi- return themtothematerialstable. Dry themetalsampleswithapapertoweland samples. Repeat steps1Ð4fortheotherthreemetal splashing anywater, asshownin ple. Letthesampleslidedowncylinderwithout Tilt thecylinderandcarefullyinsertmetalsam- aluminum, copper, iron,lead,tin,tungsten,and zinc. volume ofwaterplusmetalsample. and thattherearenoairbubbles. Then recordthe sure thatthesampleiscompletelyunderwater 2 sample. Recordtheresultsin CHEMISTRY SMALL-SCALELABORATORY MANUAL Figure A. oueo Vlm fwtr Volume of Volume of water Volume of Data Table1. Make Look upthedensitiesoffollowingmetals: Data Table 1 ape(L ape(L Density (g/mL) sample(mL) sample (mL)

aeClass Date 10

Chemistry Small-Scale LaboratoryManual 20

Data Table1. 30

Figure A 40

Water

m

L 50 Metal sample

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 5. 4. 3. 2. Name LAB in thelab. metal itismadeof.Calculatethepercentageerrorif any. Explain possiblesourcesoferror ples. Comparethedensityyoucalculatedforeachsample withtheaccepteddensityof Thinking Critically Applying Concepts Drawing Conclusions not before,wouldthataffect thedensityvalueyoucalculatedforthatsample?Explain. Describe twowaysyoucoulddeterminewhetherthesampleismadeoftinorzinc. in question1.Decidewhichmetaleachsampleislikelytorepresent. Error Analysis 2 Find outfromyourteacherwhetheryoucorrectlyidentified thesam- CHEMISTRY SMALL-SCALELABORATORY MANUAL Suppose youcalculatedthedensityofametalsampletobe7g/mL. If therewereairbubblesinthewaterafteryouaddedasamplebut Assume thatthesamplesyoutestedmaybeanyofmetals aeClass Date 7 8 Name Real-World Chemistry 1. LAB 10 percentbodyfat?Explain. than apersonofthesamemasswhohas body fattofloathigherorlowerinthewater Would youexpectapersonwhohas30percent water. Fattytissueislessdensethanwater. includes muscleandbone,ismoredensethan tissue orfattytissue.Leantissue,which person Body compositionreferstothepercentageofa 2 ’ s bodymassthatiscomposedoflean CHEMISTRY SMALL-SCALELABORATORY MANUAL 3. 2. density ofpurecopper?Explain. expect thedensityofbrasstocompare alloy ofcopperandzinc.Howwouldyou of twoormoremetals.Forexample,brassisan Many metallicmaterialsarealloys,ormixtures such asironandlead? these metalsarepreferredoverothermetals, has adensityof4.5g/mL. Why doyouthink aluminum andanothermetal,titanium,which Modern jetairplanesarebuiltprimarilyoutof aeClass Date Chemistry Small-Scale LaboratoryManual

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. O Separation of Aspirin Chemistry Small-Scale LaboratoryManual 5. 4. 3. 2. 1. Pre-Lab Safety Precautions tablet? substances inanaspirin How canyouseparatethe Problem Name tlatfu usacs aspirin,starch,salicylicacid,andaceticacid. at leastfoursubstances: and aceticacidovertime.Therefore,anaspirintabletisamixtureof easy handling.Furthermore,aspirincanbreakdownintosalicylicacid keeps thetabletsfromfallingapartandmakesthemlargeenoughfor than aspirin,however. Manufacturersmixaspirinwithstarch,which Separation of Aspirin why. Recordyourhypothesis onpage10. tablets willcontainmoresalicylic acid.Explain hypothesis aboutwhethernew oroldaspirin Read theentirelaboratory activity. Form a points? in asolutionbasedondifferences intheirboiling What techniqueisusedtoseparatethesubstances neous mixturecomposedofasolidandliquid? filtration Which technique nitrogen andoxygeninair. or homogeneous:saltandwater, sandandwater, Classify thefollowingmixturesasheterogeneous mixture andahomogeneousmixture? What isthedifference betweenaheterogeneous LAB which iscommonlycalledaspirin.Anaspirintabletcontainsmore ne ofthemostfrequentlyusedpainrelieversisacetylsalicylicacid, — is mostusefulforseparatingaheteroge- 3 — distillation, crystallization,or LABORATORY MANUAL CHEMISTRY SMALL-SCALE • • • • Objectives • • old aspirintablets. salicylic acidinnewand into twophases. Compare Test Test Separate acid. the presenceofsalicylic presence ofstarch. Use care whenhandlingallsolutions. Always wearsafetygoggles,gloves,andalabapron. one ofthephasesfor each phaseforthe the amountof an aspirintablet 4. 3. 2. 1. Procedure the bottomofwell. Allow thesolidmaterialin well A1 tosettle to toothpick. hol towell A1. Stirthemixtureinwell A1 witha Use thepipettetoadd40dropsofisopropylalco- microplate. to scrapethegroundtabletintowell A1 ofthe pieces withthemortarandpestle.Usespatula intosmall Grind anaspirintabletfromgroup A microplate. Place asheetofwhitepaperbeneaththe24-well aeClass Date iodine solution iron(III) nitrate isopropyl alcohol aspirin tablets Materials solution (2-propanol) (1 old,1new) sheet ofwhite toothpicks (2) spatula thin-stem pipette 24-well microplate mortar andpestle paper 9 10 Data andObservations 11. 10. Name 9. 8. 7. 6. 5. elObservations Well A3 A2 A1 B3 B2 B1 LAB Table 1. your observationsin color ofthecontentsthesewells.Record A3 andB3.Stirwithatoothpick.Comparethe Add 1dropofiron(III)nitratesolutiontowells happens tothecontentsofeachwellin B1, andB2.Stirwithatoothpick.Recordwhat Add 1dropofiodinesolutiontowells A1, A2, group BandwellsB1 Repeat steps2 Clean anddrythemortarpestle. well A3. Transfer 10dropsoftheliquidinwell A2 to Repeat steps3 Place theliquidinwell A2. tablet thatcandissolveinisopropylalcohol. propyl alcoholandanysubstancesintheaspirin the solidmaterial. The liquidconsistsofiso- A1. Use thepipettetoremoveliquidfromwell your mouth. ATO:Never placethepipettein CAUTION: 3 Be carefulnottodrawupanyof Ð Ð 7 usinganaspirintabletfrom 5. CHEMISTRY SMALL-SCALELABORATORY MANUAL Data Table1. Ð B3 ofthemicroplate. Data Data Table 1 Cleanup andDisposal Hypothesis 3. 2. 1. detergent beforeyouleavethe lab. Wash yourhandsthoroughlywithsoapor Return alllabequipmenttoitsproperplace. teacher. Dispose ofallsolutionsasdirectedbyyour aeClass Date Chemistry Small-Scale LaboratoryManual

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 6. 5. 4. 3. 2. 1. Analyze andConclude Name LAB predictions ofyourhypothesis.Explainpossiblereasons foranydisagreement. and whichcontainednewaspirin. Then comparetheresultsofthisexperimentwith the new sample? andgroupB. the amountofsalicylicacidinaspirintabletsfromgroup A color thatresultswheniron(III)nitratesolutionisadded.Usingthisinformation,compare propyl alcohol?Explain. acid. Usingthisinformation,canyoudeterminewhethersalicylicaciddissolvesiniso- Explain. Using thisinformation,canyoudeterminewhetherstarchdissolvesinisopropylalcohol? Drawing aConclusion Drawing aConclusion Observing andInferring Observing andInferring Applying Concepts homogeneous mixtureoraheterogeneousmixture?Explain. Error Analysis 3 idotfo ortahrwihgop( orB)containedoldaspirin Find outfromyourteacherwhichgroup(A CHEMISTRY SMALL-SCALELABORATORY MANUAL Does addingisopropylalcoholtoacrushedaspirintabletmake hc alt( orB)wastheoldsampleandwhich Which tablet(A The moresalicylicacidasolutioncontains,thedarkerviolet Iron(III) nitratesolutionturnsvioletwhenaddedtosalicylic Iodine solutionturnsblueorblackwhenaddedtostarch. aeClass Date 11 12 Name Real-World Chemistry 2. 1. LAB sodium chloridefromseawater. Describe asimplemethodforseparating also themajorsubstancedissolvedinseawater. nutrient forhumansandotheranimals.Itis Sodium chloride(tablesalt)isanessential 5.0 g/mL.) of sandandgravelrangesfromabout2.5to density ofgoldis19.3g/mL,andthe materials undertheseconditions.(Hint: The Explain whythegoldseparatesfromother swirls thepanunderagentlestreamofwater. lar panwithgold-containingsandorgraveland personusingthismethodfillsacircu- mixed. A the othermaterialswithwhichitisoften Panning isamethodforseparatinggoldfrom 3 CHEMISTRY SMALL-SCALELABORATORY MANUAL 3. the piecesarethoroughlymixedtogether? iron, evenifallofthecansaregroundupand separate aluminumcansfrommadeof grams donot.Howmightrecyclerseasily two kindsofcansseparate,whileotherpro- iron. Someprogramsaskcitizenstokeepthe for bothaluminumcansandmadeof Many communitieshaverecyclingprograms aeClass Date Chemistry Small-Scale LaboratoryManual

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. T Properties ofElements Periodicity andthe Chemistry Small-Scale LaboratoryManual 4. 3. 2. 1. Pre-Lab Safety Precautions alkaline earthmetals? compounds containing patterns ofsolubilityfor How canyoudemonstrate Problem Name will demonstratepatternsofsolubility. dissolve inagivenamountofanothersubstance.Inthisactivity, you solubility. Solubilityreferstotheamountofasubstance thatcan element byexaminingitspositioninthetable.Onesuchpropertyis properties. Thus,itispossibletopredictmanyofthepropertiesan Elements inthesamegrouphavesimilarchemicalandphysical rows calledperiodsandverticalcolumnsgroupsorfamilies. Properties ofElements Periodicity andthe Name thealkalineearthmetals. atomic numberformetals in thesamegroup? What istherelationshipbetween reactivityand identical properties? Why don periodic tablehavesimilarproperties? Why doelementsinthesamegroupon LAB to theiratomicstructures.Thetableisarrangedinhorizontal he periodictableofelementsorganizestheaccording ’ t elementsinthesamegrouphave 4 LABORATORY MANUAL CHEMISTRY SMALL-SCALE • • • • • Objectives • • metals. containing alkalineearth solubility forcompounds Recognize Observe Prepare solutions. cals areaddedtothese form whenotherchemi- of alkalineearthmetals. solutions containingions Dispose ofallsolutionsasdirected byyourteacher. Notify yourteacherofanyspills. Use extracare whenhandlingallsolutions. Always wearsafetygoggles,gloves,andalabapron. serial dilutionsof precipitates that patterns of 5. page 14. this experiment.Recordyourhypothesison containing alkalinemetalsthatyouwilltestin hypothesis aboutthesolubilityofcompounds Read theentirelaboratoryactivity. Forma aeClass Date solutions of: 96-well Materials Na Na Na Ba(NO Sr(NO Ca(NO Mg(NO microplates (3) 2 2 2 CO C SO 2 3 O 4 3 3 3 ) 3 ) ) 2 4 2 2 ) 2 distilled water toothpicks (45) thin-stem 96-well sheets ofblack pipettes (7) templates (3) paper (15) construction 13 14 11. 10. Procedure Name 9. 8. 7. 6. 5. 4. 3. 2. 1. LAB well C1,and10dropsofBa(NO tains asolution. Formed by Adding Na transfer thesolutions. may usethesamepipettesyouusedbeforeto Using acleanmicroplate,repeatsteps2 Template 1. Indicate whichwellscontainaprecipitateon itate (solidmaterialatthebottomofwell). Examine eachwellforthepresenceofaprecip- Add 5dropsofNa steps 5 Using adifferent pipettefor eachrow, repeat well A12. Remove anddiscard5dropsofthesolutionin Figure A. the nextthroughwell A12, asdiagrammedin Continue transferring5dropsfromonewellto well A2. Mixthoroughlywithatoothpick. Transfer 5dropsofthesolutioninwell A1 to A2 Add 5dropsofdistilledwatertoeachwells “ that areinwells A1 Label allthreetemplatestoshowthesolutions mouth. Never placethepipetteinyour CAUTION: 10 dropsofMg(NO Using adifferent pipetteforeachsolution,place with theletteredrowsonleft. Place amicroplateontheconstructionpaper Na Template 2 Ca(NO Precipitate Formedby Adding Na 2 Ð C A12, B2 Figure A 2 4 O Ð 3 ) 7 forrowsB,C,andD. 4 2 . ” in wellB1,10dropsofSr(NO Title Template3 “ Ð Precipitate Formedby Adding B12, C2 Mg(NO Ba(NO Ca(NO Sr(NO 2 CHEMISTRY SMALL-SCALELABORATORY MANUAL Ð SO 3 D1. Title Template1 ) 3 3 3 3 2 Ð ) ) ) ) 2 4 2 2 2 2 in well A1, 10dropsof CO C12, andD2 to eachwellthatcon- 3 . D C B A ” “ Precipitate 1 Transfer 5dropsfromonewelltothenext. 3 H H H H ) 2 2 2 2 2 2 2 O O O O SO in wellD1. Ð H H H H D12. 3 2 2 2 2 4 O O O O Ð . ” 3 8. You H H H H Title ) 4 2 2 2 2 2 O O O O in H H H H 5 2 2 2 2 O O O O H H H H 6 2 2 2 2 O O O O Hypothesis 16. 15. 14. 13. 12. observations. Use yourthreetemplatestorecord Data andObservations Cleanup andDisposal H H H H 3. 2. 1. 7 2 2 2 2 O O O O H H H H contains asolution. contains asolution. on Template3. itate. Indicatewhichwellscontainaprecipitate Examine eachwellforthepresenceofaprecip- Add 5dropsofNa transfer thesolutions. may usethesamepipettesyouusedbeforeto Using acleanmicroplate,repeatsteps2 on Template2. itate. Indicatewhichwellscontainaprecipitate Examine eachwellforthepresenceofaprecip- Add 5dropsofNa detergent beforeyouleavethe lab. Wash yourhandsthoroughlywithsoapor Return alllabequipmenttoitsproperplace. directed byyourteacher. Dispose ofallchemicalsandsolutionsas 8 2 2 2 2 O O O O aeClass Date H H H H 9 2 2 2 2 O O O O H H H H 10 2 2 2 2 Chemistry Small-Scale LaboratoryManual O O O O H H H H 11 2 2 2 2 O O O O H H H H 12 2 2 2 2 O O O O 2 2 CO C Discard 5drops. 2 O 3 4 to eachwellthat to eachwellthat Ð 8. You

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 5. 4. 3. 2. 1. Analyze andConclude Name Real-World Chemistry 2. 1. LAB possible reasonsforanydisagreement. concentration? containing thesemetals. describe thegeneralpatternofsolubilityfrommagnesiumtobariumcompounds precipitates inwellswithalowerconcentrationofmetalions.Usethisinformationto Drawing aConclusion Observing andInferring Collecting andInterpreting Data Measuring andUsingNumbers precipitates astheconcentrationbecamemoredilute? microplates. (amount ofmetalionperdropsolution)variedwithineachrowwellsonthe Error Analysis equal concentrations?Explain yourreasoning. to suchdepositsifbothions werepresentin calcium experiment, whichmetalion clog pipes.Basedonyourobservationsinthis ate (CO magnesium orcalciumionsalongwithcarbon- Water thatcontainshighconcentrations of naturally incompoundsthat almostalwaysare The alkalineearthmetalberyllium exists 4 3 — ) ionscanformdepositsthatmay do youthinkwouldcontribute more Compare theresultsofthisexperimentwithyourhypothesis.Explain CHEMISTRY SMALL-SCALELABORATORY MANUAL Compounds withalowersolubilityinwaterwillform Which alkalineearthmetal(s)didnotformprecipitatesatany — magnesium or Explain howtheconcentrationofalkalineearthmetals Which alkalineearthmetal(s)continuedtoform 3. from thesemixtures. why itisdifficult toisolatepureberyllium mixed withaluminumcompounds.Explain Why? metals couldbeusedforthis kindoftreatment? cancerous tissue. Which ofthealkalineearth in asealedtubeandinserting thetubein placing smallamountsofaradioactiveelement Physicians cantreatsometypesofcancerby aeClass Date 15

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. L Properties of Transition Metals Chemistry Small-Scale LaboratoryManual 4. 3. 2. 1. Pre-Lab Safety Precautions from othermetals? be distinguishedchemically How cantransitionmetals Problem Name transition metalsdiffer chemicallyfromothermetals. in theirelectronconfigurations.Inthisactivity, youwilldiscoverhow transition metalsthemselves.Thisvariabilityresultsfromdifferences metals. Therealsoisconsiderablevariabilityinthepropertiesof chemical propertiesdistinguishthetransitionmetalsfromother Properties of Transition Metals hypothesis aboutwhichthree metalionswillhave Read theentirelaboratory activity. Form a group 1Bmetals,ortransition metals. metals, Characterize thetenmetalsasgroup1A Co, Ni,Cu,andZn). tested inthisexperiment(K,Ca, V, Cr, Mn,Fe, Identify themetalsintensolutionstobe What aretransitionmetals? LAB ike othermetals,transitionmetalsaremalleable,lustrous,and good conductorsofelectricity. However, avarietyofphysicaland 5 LABORATORY MANUAL CHEMISTRY SMALL-SCALE • • • • • • • • Objectives • • other metalions. metal ionswiththatof reactivity oftransition Compare Observe Observe ions inaqueoussolution. properties oftenmetal solutions. with eachofthe mixing threechemicals Do notinhalevaporsthatare released. Do notdisposeofwastesinthesinkortrashcan. Notify yourteacherofanyspills. Use extracare whenhandlingallsolutions. Do notmixHClandKSCN. irritate theeyes,skin,andrespiratory tract. Several solutionsare poisonous.HCliscorrosive, andHClNH Always wearsafetygoggles,gloves,andalabapron. the physical the resultsof the chemical 2. 1. Procedure lettered rowsontheleft. Set themicroplateontopof thetemplatewith Label the96-welltemplate asshownin hypothesis onpage18. the othermetalions.Explainwhy. Recordyour properties thataremostdifferent fromthoseof aeClass Date 0.1 thin-stem 96-well microplate 96-well template Materials 0.1 0.1 0.1 0.1 pipettes (15) M M M M M Mn(NO Cr(NO NH Ca(NO KNO 4 VO 3 3 3 ) 3 3 ) 3 2 ) 2 toothpicks (40) 6 0.1 0.1 0.1 1 6 0.1 0.1 M M M M M M M M HCl KSCN NH Ni(NO Co(NO Fe(NO Zn(NO Cu(NO 3 Figure A. 3 3 3 3 3 ) ) ) ) ) 2 3 2 2 2 3 will 17 18 Data andObservations 5. 4. 3. Figure A Name HCl KSCN NH Zn(NO Cu(NO Ni(NO Co(NO Fe(NO Mn(NO Cr(NO NH Ca(NO KNO LAB 3 toothpick. B1 Add 5dropsof6 example, place5dropsof0.1 tion assignedtoeachcolumnonthetemplate.For Repeat step3forcolumns2 Use apipettetoplace5dropsof0.1 of wells A2, B2,C2,andD2. Never placethepipette inyour mouth. each ofwells A1, B1,C1,andD1. ouinslto NH solution Solution 4 VO Ð 3 D C B A B10. Stirthemixtureineachwellwitha 3 3 3 3 3 3 3 ) ) ) 3 3 ) ) ) ) 2 3 3 2 2 2 2 ) 1 2 5

KNO3 2345678910

Ca(NO3)2 M NH4VO3 NH CHEMISTRY SMALL-SCALELABORATORY MANUAL Color of

3 Cr(NO3)3 to eachofwells Mn(NO ) Ð 3 2 10, usingthesolu- M

Ca(NO Fe(NO3)3 CAUTION:

M Co(NO3)2 KNO 3 )

2 Ni(NO3)2 in each 3

Data Table 1 Cu(NO ) in 3 2

3 Zn(NO3)2 Cleanup andDisposal Hypothesis 7. 6. 3. 2. 1. Effect ofaddingotherchemicals Add 5dropsof6 Add 5dropsof1 lab. Wash yourhandsthoroughlybeforeyouleavethe Return alllabequipmenttoitsproperplace. by yourteacher. Dispose ofallchemicalsandsolutionsasdirected toothpick. toothpick. D1 C1 Ð Ð aeClass Date C10. Stirthemixtureineachwellwitha D10. Stirthemixtureineachwellwitha Chemistry Small-Scale LaboratoryManual SNHCl KSCN M M HCl toeachofwells KSCN toeachofwells

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 4. 3. 2. 1. Analyze andConclude 2. 1. Name LAB possible reasonsforanydisagreement. tion, doesthatmeanareactiondidnotoccur?Explain. chemicals? Observing andInferring Thinking Critically Observing andInferring no precipitateformationorcolorchange,write there wasacolorchangewithoutprecipitateformation,indicatethenewcolor. Iftherewas a reactionthatformedprecipitate,indicatethecolorofprecipitatein For eachofwellsB1 Note thecolorofeachsolutioninwells A1 Error Analysis 5 Compare theresultsofthisexperimentwithyourhypothesis.Explain Ð CHEMISTRY SMALL-SCALELABORATORY MANUAL D10, notewhetherornottherewasachemicalreaction.If If noprecipitatewasformedwhenachemicaladdedtosolu- Which solutionsdidnotappeartoreactwithanyoftheother Which mixturescausedprecipitatestoform? Ð A10. Recordyourobservationsin none in Data Table1. aeClass Date Data Table1. Data Table1. If 19 20 Name Real-World Chemistry 1. LAB metals.) such asthe Explain yourreasoning.(Hint:Useareference would beeasiesttoseparatebydistillation? the period4transitionmetals,whichmetal solid. Iftherewereamixturecontainingallof gas torecoverthatcomponentasaliquidor ponents turnsintoagasandthencoolingthe temperature ofamixtureuntiloneitscom- other elements.Distillationinvolvesraisingthe separate aspecificmetalfrommixtureof Distillation isonemethodthatcanbeusedto Physics 5 to findtheboilingpointsofthese CRC HandbookofChemistryand CHEMISTRY SMALL-SCALELABORATORY MANUAL 3. 2. transition metalsareusedforsuchalloys. high-speed metal-cuttingtools.Explainwhy armor plate,safes,transmissiongears,and in alloysthatareusedtomakeproductssuchas chromium, manganese,andnickel,areincluded Many transitionmetals,includingvanadium, cobalt chlorideinkonheatedpaper. results inthisexperimenttopredictthecolorof the messagewrittenbypen.Useyour with apen.However, heatingthepaperreveals detectable markwhenitisappliedtopaper “ Cobalt chloridesolutioncanbeusedasan invisible ink. aeClass Date Chemistry Small-Scale LaboratoryManual ” The solutionleavesno

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Modeling MolecularShapes Chemistry Small-Scale LaboratoryManual 5. 4. 3. 2. 1. Pre-Lab Safety Precautions laboratory? shapes ofmoleculesinthe How canyoumodelthe Problem Name In thisactivity, youwillmodelshapesofmolecules. repulsion (VSEPR)model,whichisusedtopredictmolecularshapes. factors aretakenintoaccountbythevalenceshellelectronpair and thenumberofunshared(lone)pairselectrons.Thesetwo two factors:thenumberofcovalentbondsformedbyeachatom, A Modeling MolecularShapes electrons. Recordyourhypothesisonpage22. of 2,3,4,and5atomswithnolonepairs hypothesis abouttheshapesofmoleculesmade Read theentirelaboratoryactivity. Forma What ishybridization? shared bondingorbitals? Why? What effect dolonepairsofelectronshaveon molecular shape? the repulsionofelectronpairsinpredicting How doesthe VSEPR model takeintoaccount bond? How doesacovalentbonddiffer fromanionic LAB molecule consistsoftwoormoreatomsheldtogetherby covalent bonds.Theshapeofamoleculedependsprimarilyon 6 LABORATORY MANUAL CHEMISTRY SMALL-SCALE Balloonscontaininglatexmaycauseallergicreactions. • Alwayswearsafetygogglesandalabapron. • • Objectives • Observe Construct balloons. ecules byusinginflated molecular shape. of electronsaffects bonds andlonepairs the numberofcovalent how varying models ofmol- 5. 4. 3. 2. 1. Procedure the modelin the hydrogenmolecule,H balloon, asshownin the tapelooponeachballoonstickstoother Push twooftheroundballoonstogethersothat opposite wheretheknotistied. pear-shaped balloons,putthetapeonend Attach onetapelooptoeachballoon.Onthe side ofthetapeshouldfaceout. ping thetapearoundtwofingers. The adhesive For eachballoon,makealoopoftapebywrap- and tietheirendsclosed. Inflate fourpear-shaped balloonstothesamesize their endsclosed. Inflate theroundballoonstosamesizeandtie aeClass Date string clear adhesivetape pear-shaped balloons(6) round balloons(4) Materials Data Table1. Figure A. 2 . Describetheshapeof This isamodelof 21 22 10. Name 9. 8. 7. 6. LAB trichloride, AlCl of berylliumdichloride,BeCl model in model. their attachedroundballoons fromtheCH Remove twoofthepear-shaped balloonsand loons inthe AlCl the knottedendsofthreepear-shaped bal- Use stringtotieafourthpear-shaped balloonto loons intheBeCl the knottedendsoftwopear-shaped bal- Use stringtotieathirdpear-shaped balloonto balloon, asshownin balloon totheotherendofeachpear-shaped two pear-shaped balloons. Attach around Use stringtotietogethertheknottedendsof Disassemble theH methane, CH should resemble shaped balloon. The resultingstructure,which balloon totheotherendoffourthpear- in shape ofthemodelin resemble balloon. The resultingstructure, whichshould balloon totheotherendofthirdpear-shaped Data Table1. 6 Data Table1. Figure C, 4 . Describetheshapeofmodel 3 Figure D, 3 . Describetheshapeof 2 model. Attach a round 2 model. Attach around CHEMISTRY SMALL-SCALELABORATORY MANUAL model. is amodelofaluminum Figure B. Data Table1. is amodelof iueCFigure D Figure C Figure A Figure B Figure Figure A 2 . Describethe This isamodel 4 Cleanup andDisposal Hypothesis 12. 11. 2. 1. detergent beforeyouleavethelab. Wash yourhandsthoroughlywithsoap or Return alllabequipmenttoitsproperplace. CH shaped balloonsinthepartiallydisassembled to theknottedendsoftworemainingpear- Use stringtotiethelarge pear-shaped balloons of electrons. large pear-shaped balloonrepresentsalonepair shaped balloons. Tie theirendsclosed.Each are atleasttwicethesizeofotherpear- Inflate twopear-shaped balloonssothatthey in of water, H aeClass Date Data Table1. 4 model. The resultingstructure isamodel Chemistry Small-Scale LaboratoryManual 2 O. Describetheshapeofmodel

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 4. 3. 2. 1. Analyze andConclude Data Table1. Calculate thebondanglesineachofmodelsyouconstructed.Record Data andObservations Name oeueSaeBondangle(°) Shape H CH AlCl BeCl H Molecule LAB show thatthesemoleculeshavethesameshape?Explainwhyornot. modeled? Predicting Observing andInferring Applying Concepts Models Formulating pear-shaped balloon?(Hint: Think abouttheshapeofeachballoon.) 2 2 O 4 3 2 6 Predict theshapesoffollowingmolecules:CH CHEMISTRY SMALL-SCALELABORATORY MANUAL What hybridorbitalsareformedineachofthemoleculesyou What typeoforbitalisrepresentedbyaroundballoon? A Both BeCl 2 and H Data Table 1 2 O containthreeatoms.Doyourmodels aeClass Date 3 Cl, Cl 2 , CCl 4 , HCl,BF 3 . 23 24 5. Name Real-World Chemistry 2. 1. LAB hypothesis. Explainpossiblereasonsforanydisagreement. Error Analysis and ethyne. Predict theshapesandbondanglesofethene effect onmolecularshapeas singlebonds. and thetriplebondinethynehavesame welding torches. The double bondinethene VSEPR modeltopredicttheshapeofpart nitrogen atomsandoneoxygenatom.Usethe atom inhemoglobinformsbondswithfive transports oxygeninyourblood.Eachiron Hemoglobin isaniron-containingmoleculethat Ethyne, H which plasticbagsandmilkjugsaremade. material forthesynthesisofpolyethylene,from Ethene, H 6 2 — C C CH Compare theresultsofthisexperimentwithpredictionsyour C CHEMISTRY SMALL-SCALELABORATORY MANUAL — 2 , servesasthestarting H, isusedasafuelfor 3. Table 9-3inyourtextbook.) of sharedelectronpairsinvolvedandreferto atoms itbondswith.(Hint:Countthenumber of hemoglobinthatconsistsironandthe atoms.) carbon atomscanformbondswithother Explain whyornot.(Hint:Rememberthat cules thatcontainberylliuminsteadofcarbon? same varietyofshapesbepossibleformole- plex, three-dimensionalshapes. Would the these moleculesareverylarge andhavecom- ferent carbon-containingmolecules.Manyof Living thingsaremadeofahugevarietydif- aeClass Date Chemistry Small-Scale LaboratoryManual

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Solutions andPrecipitates Chemistry Small-Scale LaboratoryManual 5. 4. 3. 2. 1. Pre-Lab Safety Precautions they aremixed? form aprecipitatewhen two aqueoussolutionswill Can youpredictwhether Problem Name compounds, youcanpredictwhetheraprecipitatewillbeformed. writing ionicequationsandknowingthesolubilitiesofspecific double-replacement reactionistheformationofaprecipitate.By may takepartinadouble-replacementreaction.Oneoutcomeof A Solutions andPrecipitates mixtures listedin Table 1. Read theentirelaboratoryactivity. Study ionic equationandanetequation? What isthedifference betweenacomplete What isaspectatorion? reactions? that canformfromdouble-replacement What arethethreetypesofproducts What isadouble-replacementreaction? hypothesis onpage26. will forminthosemixtures. Recordyour a precipitate.Explainwhy aprecipitate LAB queous solutionsofioniccompoundscontaindissolvedpositive and negativeions.Whentwosuchsolutionsaremixed,theions Form ahypothesisaboutwhich 7 Data Table1 LABORATORY MANUAL CHEMISTRY SMALL-SCALE • • • • • • • Objectives • solutions. for mixturesofaqueous Observe Predict Write will formprecipitates. precipitate formation. Never placethepipetteinyourmouth. Do notdisposeofwastesinthesinkortrashcan. Notify yourteacherofanyspills. Use extracare whenhandlingthesolutions. Always wearsafetygoggles,gloves,andalabapron. will form ionic equations which mixtures mixtures for Table 1 Pb Na K Fe Cu Cl Ba Cation 3 2 2 2 Solubility ofIonicCompoundsinWater aeClass Date 1.0 1.0 1.0 1.0 Materials 1.0 1.0 M M M M M M PIPSII SSSSSS SSSSSS S SISSIS SIISPI KI FeCl CuSO BaCl Na NaCl 2 CO CO 3 2 — S P I 3 4 — 2 — — 3 insoluble soluble partially soluble Key I SIS I SS Anion NO pipettes (9) 24-well microplate 1.0 1.0 1.0 3 M M M Pb(NO Na NaOH OH 2 SO 4 3 ) SO 2 4 2 25 26 Data andObservations 4. 3. 2. 1. Procedure Name itr ouin elObservations Well Solutions Mixture LAB microplate. solution inthatmixturetoawellonthe in Repeat steps1 Record thenumberandletterofwellin allow thetipofpipettetotouchmixture. solution inthemixturetosamewell.Donot ofthesecond Use adifferent pipettetoadd5mL Choose anyoneofthemixtureslistedin Table 1. mixture. Table 1. 1NaClandCuSO Na 11 10 9Na8Na7Na KIandPb(NO 6Na KIandNaCl 5 KIandNaOH 4 FeCl 3 CuSO 2 1 Data Table1. 7 s iet oad5m ofthefirst Use apipettetoadd5mL 2 2 2 2 2 Ð CO CO CO SO SO 3 3 fortheothertenmixtureslisted 4 and NaOH Use adifferent wellforeach 4 4 3 3 3 and NaOH and Pb(NO and BaCl and CuSO and KI and BaCl CHEMISTRY SMALL-SCALELABORATORY MANUAL 3 ) 4 2 2 2 4 3 ) 2 Data Data Data Table 1 3. 2. 1. Cleanup andDisposal Hypothesis the lab. Wash yourhandsthoroughlybeforeyouleave Return alllabequipmenttoitsproperplace. by yourteacher. Dispose ofallchemicalsandsolutionsasdirected aeClass Date Chemistry Small-Scale LaboratoryManual

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 4. 3. 2. 1. Analyze andConclude 2. 1. Name LAB replacement reaction.Explainhowyouknowareactionoccurredinthosemixtures. Thinking Critically Applying Concepts Observing andInferring signs in If thereareanyothersignsthatareactionhasoccurredinofthewells,describethose precipitate isvisible.Recordtheresultsin Carefully observeeachwellthatcontainsamixtureofsolutionsandnotewhetherornot Explain possiblereasonsforanydisagreement. tures thatdidnotformaprecipitate? Error Analysis 7 Data Table1. Compare theresultsofthislabwithpredictions yourhypothesis. CHEMISTRY SMALL-SCALELABORATORY MANUAL Why isitimpossibletowriteanetionicequationforanyofthemix- Write thecompleteionicequationsofreactionsthatoccurred. Write thenumbersofmixturesthatresultedinadouble- Data Table1. aeClass Date 27 28 Name Real-World Chemistry 2. 1. LAB relieve anupsetstomach,youmaytake much HCl,anupsetstomachmayresult. To digest yourfood. When thesecellssecretetoo hydrochloric acid(HCl),whichhelpsyou Cells thatlineyourstomachsecrete (AgNO mix thesamplewithasolutionofsilvernitrate amount ofNaClinasampleseawateristo chloride (NaCl).Onewaytomeasurethe compounds, themajoroneofwhichissodium Seawater isadilutesolutionofseveralionic work. (Hint: AgCl isinsolubleinwater.) 7 3 ). Explainhowthismethodislikelyto CHEMISTRY SMALL-SCALELABORATORY MANUAL 3. NaHCO HCl. What wouldbeonedisadvantageofusing Mg(OH) antacid, suchasmagnesiumhydroxide, Sodium hydrogencarbonate(NaHCO stomach? equation forthereactionbetweenNaHCO also beusedasanantacid. Write thenetionic the product? net ionicequationsforthisreaction. What is precipitate isformed. Write thecompleteand HCl inadouble-replacementreaction,butno aeClass Date 3 2 instead ofMg(OH) . Magnesiumhydroxidereactswith Chemistry Small-Scale LaboratoryManual 2 to treatanupset 3 ) can 3 and

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Determining Avogadro Chemistry Small-Scale LaboratoryManual Safety Precautions stearic acid? stearic acidareinamoleof How manymoleculesof Problem Name molecules inamolewas6.004 thick, oramonolayer. In1924,itwasestimatedthatthenumberof the surfaceofwater. Thelayerwasassumedtobeonemolecule number. Inoneexperiment,athinfilmofchemicalwasspreadon might be.Lateron,otherscientistscalculatedavalueforAvogadro number ofmolecules.Buthenevercalculatedwhatthat rectangular solidandthenacylindricalsolid. experiment, theshapeofmoleculeisfirstassumedtobea precise thecalculationofAvogadro assumed shapeistotheactualofmolecule,more stearic acidtothenumberofmolesacid.Thecloser number isthenestimatedastheratioofmolecules number ofmoleculesinthemonolayercanbeestimated.Avogadro assumption ismadeabouttheshapeofasinglemolecule, stearic acid.Themonolayerformedisonemoleculethick,soifan of molesstearicacidcanbecalculatedusingthemolarmass stearic acidmoleculesonthewater surface. Thesolventwillquicklyevaporate,leavingthenonpolar stearic acidbyaddingdropsofsolutiontothewater A Determining Avogadro LAB The massofthestearicacidcanbedetermined,andnumber You willcoverthesurfaceofawatersamplewithmonolayer vogadro hypothesizedthatequalnumbersofmolesdifferent gases atthesametemperatureandpressurecontain 8 LABORATORY MANUAL CHEMISTRY SMALL-SCALE • • • • • Objectives acid molecule. the volumeofastearic mate betterapproximates Avogadro Infer Calculate monolayer. stearic acidsolutionina Measure Avoid breathing directly overthewatchglass. Always wearsafetygoggles, gloves,andalabapron. 10 ’ ’ s surface. 23 which volumeesti- s numberwillbe.Inthis . the diameterof ’ a valuefor s number. ’ ’ s Number s Number aeClass Date metric ruler 10-mL graduated 50-mL beaker lycopodium powder distilled water stearic acidsolution Materials cylinder or talcumpowder ’ ’ s s scoop test-tube rack small testtubes(2) ring stand large watchglass Pasteur pipette iron ring with suctionbulb 29 30 Procedure Pre-Lab Name 4. 3. 2. 1. 4. 3. 2. 1. LAB number? or amonolayer ofmoleculeswillnotform. times. test-tube rack. (material canberecycled) and setitinthe Label asecondsmalltesttube test tube.Setthetubeinatest-tuberack. ofstearicacidsolutionintoasmall Pour 2mL fill itwithdistilledwater. Replace thewatchglassonmetalringand water. glass andrinseitseveraltimeswithdistilled of thewatchglass. Thoroughly washthewatch Using aruler, measureandrecordthediameter at eyelevel. so thatthetopofwatchglasscanbeviewed attached toaringstand.Placetheatlevel Set thewatchglassonametalring,whichis Data Table1. mark.Recordthenumberofdropsin 1.00 mL graduatedcylindertothe needed tofilla10-mL with distilledwater. Countthenumberofdrops a suctionbulbtoPasteurpipetteandfillit beakerwithdistilledwater. Attach Fill a50-mL hypothesis inthenextcolumn. gular solidorcylindricalsolid.Recordyour precise valuefor Avogadro as towhichshapeyouthinkwillgivethemore single stearicacidmolecule.Formahypothesis assumptions aremadeabouttheshapeofa Read theentirelaboratoryactivity. Two water the chosensolventevaporatequicklyfrom dissolved inanappropriatesolvent. Why must pressure. Forthisexperiment,itmustbe Stearic acidisasolidatroomtemperatureand diameter of3.00 Calculate thevolumeofacylinderthathas What istheacceptedvaluefor Avogadro 1.00 ’ 8 s surface? ATO:Allsoapmustberinsed off CAUTION: 10 2 cm. ( Repeat thisprocesstwomore V CHEMISTRY SMALL-SCALELABORATORY MANUAL 10 cyl 4 cm andaheightof ’ ( s number d /2) “ WASTE 2 h — ) rectan- ” ’ s Cleanup andDisposal Hypothesis 10. 8. 7. 6. 5. 3. 2. 1. 9. Record thetotalnumberofdropsin a timeuntiltheaddeddropdoesnotspread. additional drop.Continuetoadddropsoneat amount ofspreadingwilldecreasewitheach has finishedspreading,addaseconddrop. The of thewaterinwatchglass. When thedrop Observe thedropasitspreadsoversurface of thesolution. center ofthewatchglass,squeezeoutonedrop While holdingthepipettedirectlyabove half oftheremainingsolution. recycled). PartiallyfillthePasteurpipettewith the testtubelabeled WASTE (materialcanbe of thestearicacidsolution.Putrinsinginto Rinse thePasteurpipettewithasmallamount der layershouldbethin powder overthesurfaceofwater. The pow- above thewatchglass,uniformlysprinkle and, whileholdingthescoopabout30cm Fill theendofascoopwithlycopodiumpowder detergent beforeyouleavethelab. Wash yourhandsthoroughlywithsoap or test tubeinthedesignatedcontainer. Dispose ofthestearicacidsolutioninwaste Wash, dry, andstoreallequipment Repeat steps7and8. with thesecondhalfofstearicacidsolution. Repeat steps3and5.FillthePasteurpipette that allofthesoapisremoved. Empty andcleanthewatchglass,makingsure Table 2. aeClass Date Chemistry Small-Scale LaboratoryManual — like alayerofdust. Data

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 6. 5. 4. 3. 2. 1. Diameter ofthewatchglass(cm): Molar massofstearicacid:284.5g/mol Concentration ofstearicacidsolution:0.10g/L Density ofstearicacid:0.9405g/cm Data andObservations Name needed toformmonolayer Drops ofstearicacidsolution Number ofdropsin1.00mL LAB volume ofonemolecule(step 5). Find thenumberofmolecules bydividingthevolumeofmonolayer(step3) bythe molecule isassumedtobearectangularsolid.( width anddepth,calculatethevolumeofonemolecule whentheshapeofstearicacid to thelengthofmolecule.Ifmolecule isassumedtobesixtimesthe The monolayerisonemoleculethick,sothethickness ofastearicacidmoleculeisequal (step 3)bytheareaofcircle.[ cylinder. To calculatethethicknessofmonolayer, dividethevolume ofthemonolayer The watchglassiscircular, sothemonolayer ofstearicacidcoveringitssurfaceisa density ofstearicacid. Calculate thevolumeofmonolayerbydividingmassstearicacid(step2) Mass ofstearicacid Use thefollowingequationtocalculatemassofstearicacid. Calculate theaveragenumberofdropsinonemilliliterforyourPasteurpipette. no. ofdropstoformmonolayer 8 CHEMISTRY SMALL-SCALELABORATORY MANUAL Concentration (g/L) Calibration ofpipette Data Table 2 Data Table 1 ra ra ri Average Trail 3 Trial 2 Trial 1 3 Area ra Trial 2 Trial 1 ( diameter 1 L/1000mL V rec (cm)/2) l w 2 aeClass Date ] 1 mL/avg.no.ofdrops d ); ( l 6 w 6 d ) 31 32 Analyze andConclude 11. 10. Name 3. 2. 1. 9. 8. 7. Real-World Chemistry simplifying assumptionsabout molecularshape compounds andchemical reactions alsomake Chemists whousecomputer simulationstomodel assumptions abouttheshapeofasinglemolecule. To calculate Avogadro LAB calculation madeassumingacylindricalsolid? value for Avogadro Observing andInferring Drawing aConclusion per mole.Calculatethepercenterrorforeachofyourcalculations Avogadro Divide thenumberofmolecules(step10)bymoles7). Recalculate Avogadro volume ofonemolecule(step9). To findthenumberofmolecules,divide thevolumeofmonolayer(step3)by be acylindricalsolid.( volume ofonemoleculewhentheshapestearicacidisassumedto If thelengthofmoleculeisassumedtobesixtimesdiameter, calculatethe divide thenumberofmolecules(step6)bymoles7). To calculate Avogadro stearic acid(step2)bythemolarmassofacid. Calculate thenumberofmolesstearicacidinmonolayerbydividingmass acid molecule Error Analysis 8 — rectangular solidorcylindricalsolid? The acceptedvaluefor Avogadro ’ CHEMISTRY SMALL-SCALELABORATORY MANUAL s number ’ s number, chemistsmade ’ ’ s number, assumingthestearicacidmoleculeisacylindricalsolid. V s numberwhenthestearicacidmoleculeisarectangularsolid, cyl Which ofyourtwocalculationscameclosertotheaccepted Which assumptionisclosertotheactualshapeof stearic — l the calculationmadeassumingarectangularsolidor ( ( d /2) 2 ); ( l 6 d ) ’ program makes. some ofthelimitationsand assumptionsthis by chemistsforcomputer simulation andlist research. Identifyandinvestigateaprogramused in ordertoperformcalculationsneededfortheir s numberis6.022 aeClass Date Chemistry Small-Scale LaboratoryManual 10 23 ’ particles s number.

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Measuring BoilingPoint Chemistry Small-Scale LaboratoryManual 5. 4. 3. 2. 1. Pre-Lab Safety Precautions substances? the boilingpointsof How canyoucompare Problem Name for moleculesthatformhydrogenbonds. In general,boilingpointsarehigherformoremassivemoleculesand hydrogen bonds substances. Two factors at whichboilingoccurs,calledthepoint,variesfordifferent only atthesurface,liquidissaidtobeboiling.Thetemperature V Measuring BoilingPoint ing. Recordyour hypothesisonpage34. has thelowestboilingpoint. Explainyourreason- will testhasthehighestboiling pointandwhich hypothesis aboutwhichof thesubstancesyou Read theentirelaboratory activity. Form a boiling point? What arethesignsthataliquidhasreachedits ing point? and externalpressurewhenaliquidisatitsboil- What istherelationshipbetweenvaporpressure Define Contrast evaporationandboiling. LAB gas. Whenvaporizationoccursthroughoutaliquidinsteadof aporization isthephasechangeinwhichaliquidchangesto vapor pressure 9 — are mostimportantindeterminingboilingpoint. LABORATORY MANUAL CHEMISTRY SMALL-SCALE . — molar massandtheabilitytoform • • • • • • • • Objectives • liquid byitsboilingpoint. liquids. points ofthreeknown Identify Correlate Measure bonds. ability toformhydrogen with molarmassandthe Acetone, ethanol,andpropanol are allflammablechemicals. Never placethepipetteinyourmouth. Do notdisposeofwastesinthesinkortrashcan. Use cautionandproper protection whenhandlinghotobjects. Notify yourteacherofanyspills. Always wearsafetygoggles,gloves,andalabapron. an unknown the boiling boiling point 5. 4. 3. 2. 1. Procedure up intoaclean,smalltest tube. Place acleancapillarytube withthesealedend the waterisheating,complete steps5and6. Turn thehotplateontoamediumsetting. While Figure A the thermometerisinwater, asshownin mometer totheringstand.Lowerclampso Use thethermometerclamptoattachther- water. Placethe beakeronthehotplate. Fill thebeakerabouttwo-thirdsfullwithtap Set thehotplateonbaseofringstand. aeClass Date capillary tubes, thermometer 100-mL beaker 1-propanol ethanol acetone Materials end (3) sealed atone ( 10 on page34. ° C to100 ° C) glass stirringrod rubber band thermometer clamp ring stand hot plate thin-stem pipette small testtubes(3) 33 34 Figure A 12. 11. 10. Name 9. 8. 7. 6. LAB Thermometer temperature in of theliquidincapillarytube.Record to thenearest0.1 Immediately readthetemperatureofwater constantly untilthestreamofbubblesstops. Use theglassstirringrodtostirwater hot plate. the openendofcapillarytube,turnoff the When asteadystreamofbubblesissuesfrom you do. bubbles, continueheatingthewateruntil of thecapillarytube.Ifyoudonotseeany Look forbubblescomingfromtheopenend shown in bly shouldbeabovethesurfaceofwater, as assembly isinthewater. The topoftheassem- Lower theclampsotesttube thermometer. should beatthesamelevelasbulbof the thermometer. The bottomofthetesttube Use therubberbandtoattachtesttube thermometer isabovethebeaker. approximately 80 When thewatertemperaturehasreached known liquidstothetesttube. ofonethe Use thepipettetoadd3mL The thermometerwillbehot. of water 9 Beaker Figure B. Data Table1. ¡ ¡ C. This istheboilingpoint C, raisetheclampso IHLOW HIGH CHEMISTRY SMALL-SCALELABORATORY MANUAL Hot plate MED OFF Ð CAUTION: thermometer Figure B Cleanup andDisposal Hypothesis 13. 3. 2. 1. with liquid different liquid. water tocleanthepipettesbeforedrawingupa liquids andtheunknownliquid.Usedistilled detergent beforeyouleavethelab. Wash yourhandsthoroughlywithsoap or Return alllabequipmenttoitsproperplace. teacher. Dispose ofallmaterialsasdirectedbyyour Repeat steps4 Test tube Capillary aeClass Date Rubber band tube Chemistry Small-Scale LaboratoryManual Ð IHLOW HIGH 12 withtheothertwoknown Hot plate MED OFF

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 5. 4. 3. 2. 1. Analyze andConclude Data andObservations Name Unknown iudMlrfruaMlrms g yrgnbnig Boiling point( Hydrogen bonding? C C Molarmass(g) C 1-propanol Molarformula Ethanol Acetone Liquid LAB Record theresultsin with theboilingpointsofknownliquids. Acquiring and Analyzing Information Drawing aConclusion Observing andInferring Thinking Critically Measuring andUsingNumbers appearing astheboilingpointofeachliquid? known liquid. reasoning. bonding 9 — seems tobemoreimportantindeterminingboilingpoint?Explainyour CHEMISTRY SMALL-SCALELABORATORY MANUAL Data Table1. 3 2 3 Why didyourecordthetemperaturewhenbubblesstopped —— —— H H H 8 5 6 yes yes O O Ono Based onyourresults,whichfactor Identify theunknownliquidbycomparingitsboilingpoint Calculate themolarmassofeachknownliquid. Look uptheacceptedboilingpointofeach Data Table 1 aeClass Date — molar massorhydrogen ° C) 35 36 6. Name Real-World Chemistry 2. 1. LAB error inthelab. the acceptedboilingpoint.Calculatepercenterror, ifany. Explainpossiblesourcesof Error Analysis whose molarmassesmaybe800gormore.) (Hint: Cookingoilisamixtureoffatmolecules chicken cookedinoilratherthanwater? Why arefoodssuchasfrenchfriesandfried an altitudeof3000m?Explain. cook noodlesinboilingwateratsealevelor they arecookedin. Would ittakelongerto depends onthetemperatureofwaterthat The amountoftimeittakestocooknoodles 9 Compare theboilingpointyoumeasuredforeachknownliquidwith CHEMISTRY SMALL-SCALELABORATORY MANUAL 3. The boilingpointof1,2-ethanediolis197 at coolinganenginethanwateralone?(Hint: ethylene glycol). Why issuch amixturebetter mostly of1,2-ethanediol(commonlycalled mixture ofwaterandantifreeze,whichconsists Most automobileenginesarecooledbya aeClass Date Chemistry Small-Scale LaboratoryManual ¡ C.)

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. T and Gas Volume Relating GasPressure Chemistry Small-Scale LaboratoryManual 5. 4. 3. 2. 1. Pre-Lab Safety Precautions volume ofthegas? pressure ofagasaffect the How doeschangingthe Problem Name With asimplelaboratorysetup,youcantesthowwellBoyle gases, whichobeyalloftheassumptionsmadebykinetictheory. behavior ofgases.Onethegaslaws,Boyle pressure andgasvolumearerelated.Boyle applies torealgases. and Gas Volume Relating GasPressure circle increases. Recordyourhypothesis onpage38. sample willchangeasthe pressure onthesample hypothesis abouthowthevolume oftheair Read theentirelaboratoryactivity. Forma increases? two variables, Suppose thereisaninverserelationshipbetween (in N/m whose radiusis6.20cm.Calculatethepressure forceof12.7Nisappliedtoacirculardisk A Define pressure. State Boyle LAB pressure, volume,andtemperature he gaslawsdescribetheinterdependenceofthreevariables 2 ) appliedtothedisk.(Hint: The areaofa 10 ’ s law. radius x and LABORATORY MANUAL CHEMISTRY SMALL-SCALE 2 y .) . What happensto • • • • Objectives Make anduseagraph ent pressures. the airsampleatdiffer- Measure matical relationship. to illustratethemathe- volume versuspressure only asdirected. Gas underpressure canbehazardous. UsetheBoyle Always wearsafetygoggles,gloves,andalabapron. the volumeof y — as that determinethe ’ x s lawappliestoideal ’ s law, stateshowgas 3. 2. 1. Procedure of Figure A. thread hangingoutoftheapparatus,asshownin the Boyle Insert alengthofcarpetthreadintothebarrel millimeter. Record thediameterin eter oftheheadplungertonearest law apparatus.Usetherulertomeasurediam- Pull theplungerallwayoutofBoyle Data Table1. object tothenearestgram.Recordmassesin Use thebalancetomeasuremassofeach aeClass Date Materials metric ruler balance carpet thread Boyle flat objectsthatcanbestacked(4) ’ s law ’ s lawapparatus.Leaveoneendofthe ’ — s lawapparatus ’ s lawapparatus Data Table1. ’ s 37 38 Data andObservations Figure A Name 6. 5. 4. tce oa rsuepressure Massofobject4(g): 1, 2,3,4 Pressure Massofobject3(g): 1, 2,3 Areaofplungerhead(m 0 (N/m 1, 2 1 Force (N) mass(kg) none Total objects Stacked Diameter ofplungerhead(mm): Mass ofobject2(g): Mass ofobject1(g): LAB for airtoescapepasttheheadasyoudothis. the barrel. The threadwillmake asmallspace volume forzerototalmassunder Record thevolumein Measure thevolumetonearest0.1cm the barrel. times toreducefrictionbetweentheheadand remove thethread. Twist theplungerseveral While holdingtheplungerinplace,carefully head oftheplungerisnear35cm Push theplungerbackintobarreluntil 10 thread Carpet CHEMISTRY SMALL-SCALELABORATORY MANUAL Data Table1 Trial 1 as the 3 mark on 2 )(N/m . 3 . Data Table 1 Total 2 12. 11. 10. Cleanup andDisposal Hypothesis ra ra ra Average Trial 3 Trial 2 Trial 1 ) 9. 8. 7. 2. 1. two moretimes.Recordtheresultsin Remove allfourmasses.Repeatsteps6 other threemasses.Repeatstep8. Carefully stackthefourthmassontopof other twomasses.Repeatstep8. Carefully stackthethirdmassontopof first mass.Repeatstep8. Carefully stackthesecondmassontopof 0.1 cm Measure andrecordthevolumetonearest plunger severaltimestoreducefriction. While stabilizingtheapparatus,twist plunger. Carefully placethefirstmassontopof Return alllabequipmenttoitsproperplace. condition asyoufoundit. Make sureyourbalanceisleftinthesame Table 1 aeClass Date 3 under under Chemistry Small-Scale LaboratoryManual Trial 1 Trial 2 Volume (cm 2 ): . and Trial 3 3 ) . Data Ð 11 11

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 4. 3. 2. 1. Analyze andConclude 6. 5. 4. 3. 2. 1. Name LAB possible reasonsforanydisagreement. and totalpressureasshownbytheresultsin radius apparatus hadchangedduringtheexperiment?Explain. Applying Concepts Collecting andInterpreting Data Making andUsingGraphs dividing by3.Recordtheresultsin For eachtotalmass,calculatetheaveragevolumebyaddingvolumesintrialand 10 (Unless yourteacherinstructsyouotherwise,assumethatatmosphericpressure pressure byaddingatmospherictotheexertedstackedobjects. The atmospherealsoexertspressureontheplunger. Foreachtotalmass,calculatethe Calculate thepressure(inN/m formula: force(N) Calculate theforce(inN)exertedonplungerbyeachtotalmass.Usefollowing the apparatus.Recordresultsin Calculate thetotalmass(inkg)whenone,two,three,orallfourobjectswereplacedon Calculate thecross-sectionalarea(inm the definitionofpressure.)Recordresultsin between thedatapoints,labelbothaxes,andgivegraphatitle. volume ontheverticalaxisandtotalpressurehorizontalaxis.Drawlines Error Analysis 5 N/m 10 2 .) Recordtheresultsin diameter/2.) Recordtheresultin Compare theresultsofthisexperimentwithyourhypothesis. Explain CHEMISTRY SMALL-SCALELABORATORY MANUAL mass (kg) Would yourresultshavebeendifferent ifthetemperatureof 2 Make agraphofvolumeversuspressure.Plottheaverage ) exertedontheplungerbyeachtotalmass.(Hint:Recall Data Table1. 9.80 m/s Data Table1. Data Table1. Describe therelationshipbetweenaveragevolume 2 ) oftheheadplunger. (Rememberthat Data Table1. 2 . Recordtheresultsin Data Table1 Data Table1. and onyourgraph. aeClass Date Data Table1. 1.0 39 40 Name Real-World Chemistry 1. LAB change duringthestroke. Assume thetemperatureofgasdoesnot pressure ofthegasatendstroke? start ofacompressionstroke,whatisthe atmospheric pressure(1.0 volume attheendofstroke.Ifgasis start ofthecompressionstrokeis8times that thevolumeofgasineachcylinderat have acompressionratioof8to1. This means gasoline engineinamodernautomobilemay typical ture offuelandairinthecylinders. A reduce thevolume(compress)agaseousmix- stroke. Inthecompressionstroke,pistons Each up-and-downmovementiscalleda move upanddowninsidehollowcylinders. Most gasolineengineshaveasetofpistonsthat 10 CHEMISTRY SMALL-SCALELABORATORY MANUAL 10 5 N/m 2 ) atthe 3. 2. same atthetwolocations. 2.3 10 700m,wherethesurroundingairpressureis helium whentheballoonisatanaltitudeof ascend tooquickly? ascends? Why isitdangerous foradiverto What happenstothesebubblesasthediver the samepressureassurroundingwater. bubbles thatmaybeinthebloodvessels,areat gases inthediver the surroundingwaterpressureincreases. The As ascubadiverdescendsthroughthewater, 1.0 at sealevel,wheretheatmosphericpressureis whentheballoonisreleased volume of200.0L The heliuminaweatherballoonoccupies aeClass Date 10 10 4 5 N/m N/m Chemistry Small-Scale LaboratoryManual 2 2 ? Assume thetemperatureis . What isthevolumeof ’ s body, includinganysmall

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. F Solubility Effect of Temperature on Chemistry Small-Scale LaboratoryManual 3. 2. 1. Pre-Lab Safety Precautions water? ammonia gasdissolvesin on therateatwhich the effect oftemperature How canyoudetermine Problem Name will determinetheeffects oftemperatureonthesolutionprocess. For othersolutes,however, theoppositeistrue.Inthisactivity, you Therefore, manysolutesdissolvemorerapidlyathighertemperatures. increases. Collisionsoccurmorefrequentlyandwithgreaterenergy. increases, theaveragekineticenergyofsoluteandsolventparticles dissolves. Oneimportantfactoristemperature.Astemperature of thesecollisionsislikelytoaffect therateatwhichsolute Solubility Effect of Temperature on solubility ofgasesinliquid solvents? How doesdecreasingthetemperature affect the most solidsthataredissolved inwater? decreasing thetemperature affect thesolubilityof Refer to Table 15-2inyourtextbook.Howdoes What issolubility? LAB must collidewitheachother. Anyfactorthataffects thefrequency or asolutetodissolveinsolvent,theandsolventparticles 11 LABORATORY MANUAL CHEMISTRY SMALL-SCALE • Donotdisposeofwastesinthesinkortrashcan. • Usecautionandproper protection whenhandlinghotobjects. • Notifyyourteacherofanyspills. • Ammoniawillirritatetheeyes,skin,andrespiratory tract.Useextra • Alwayswearsafetygoggles,gloves,andalabapron. • • • Objectives ammonia solution. from aconcentrated to solubility. the ammoniatodissolve Relate temperatures. at fourdifferent gas todissolveinwater required forammonia Measure Collect care whenhandlingtheconcentratedammoniasolution. the timeittakes ammonia gas the time 5. 4. hypothesis onpage42. temperature shouldhavethis effect. Recordyour solve inwater. Explainwhydecreasingthe will affect thetimerequiredforammoniatodis- hypothesis abouthowdecreasing thetemperature Read theentirelaboratoryactivity. Forma was doubled?Explainwhy. change ifthepressureofgasaboveliquid How wouldthesolubilityofagasinliquid aeClass Date thin-stem pipette 100-mL beaker 250-mL beaker 400-mL beaker concentrated Materials ammonia solution fume hood crushed ice stopwatch metric ruler scissors wide-stem pipette 41 42 Figure A Procedure Name 5. 4. 3. 2. 1. LAB nia gascompletelyfillthecollectingpipette. times toexpelalloftheairandhelpammo- pipette. Squeezethecollectingpipetteseveral and beginsfillingthebulbofcollecting ing pipette,ammoniagasleavesthesolution As theammoniasolutionwarmsingenerat- collecting pipette,asshownin Cover thetipofgeneratingpipettewith submerge thebulbinbeaker ofhotwater. Turn thegeneratingpipettebulb-enddownand the pipetteinfumehoodatalltimes. solution. This isthegeneratingpipette.Keep thin-stem pipettewithconcentratedammonia Working underthefumehood,halfwayfill ofhottap water. 350 mL beakerwithabout procedure. Fillthe400-mL beneath thefumehoodthroughoutentire under thefumehood.Beakersmustremain Place thethreebeakersusedinthisactivity is thecollectingpipette. pipette, leavingthestemabout4cmlong. This Use scissorstocutthetipoff thewide-stem 11 CHEMISTRY SMALL-SCALELABORATORY MANUAL solution ammonia Concentrated pipette Generating water Hot tap pipette Collecting Figure A. Figure B 10. 9. 8. 7. 6. c. b. a. ofeachthefollowing. beaker with200mL Repeat steps2through9,fillingthe250-mL water. Record the timein completely dissolvedwhenthepipetteisfullof ing pipettehasdissolvedcompletely. The gasis Stop thestopwatchwhengasincollect- Figure B. beaker, asshownin hot waterinthe250-mL Submerge thetipofcollecting pipetteinthe beaker. down inthe100-mL ing pipette.Setthegeneratingpipettebulb remove thecollectingpipettefromgenerat- After collectingammoniagasfor3 Data Table1. the nearest0.1¡C.Recordtemperaturein water. Measurethetemperatureofwaterto ofhottap beakerwith200mL Fill the250-mL by loweringthepipetteasitfillswithwater. water inthepipettenearlevelbeaker aeClass Date a mixtureofcoldtapwaterandice cold tapwater water a 50-50mixtureofhottapwaterandcold Chemistry Small-Scale LaboratoryManual Start thestopwatch.Keeplevelof Data Table1. Water pipette Collecting Ð 4 min,

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 3. 2. 1. Analyze andConclude Data Table1. Convert eachtemperatureindegreesCelsiustokelvinbyadding273.Recordtheresults Data andObservations Hypothesis Name Cold water Cold water Hot water Hot water LAB ammonia (NH Consider thedensityofgasesinvolved.) Making andUsingGraphs Applying Concepts Thinking Critically temperature (inkelvins).Connect thedatapoints,labelaxes,andtitlegraph. 11 cold water ice 3 ) insteadofairinstep5?(Hint: Air iscomposedmostlyofN CHEMISTRY SMALL-SCALELABORATORY MANUAL How canyoubesurethatthecollectingpipettewasfilledwith Explain whywaterwasdrawnintothecollectingpipette instep8. eprtr °)Tmeaue()Time(s) Temperature (K) Temperature (°C) Make agraphofdissolving time(inseconds)versus Data Table 1 Cleanup andDisposal 3. 2. 1. detergent beforeleavingthelab. Wash yourhandsthoroughlywithsoapor Return alllabequipmenttoitsproperplace. teacher. Dispose ofallsolutionsasdirectedbyyour aeClass Date 2 and O 2 . 43 44 5. 4. Name Real-World Chemistry 2. 1. LAB Provide anexplanationforanydisagreement. given forammoniain Table 15-2inyourtextbook. temperature onthesolubilityofammoniainwater?Comparethisconclusionwithdata Observing andInferring Error Analysis pools iswarm.Explainwhy. will gulpairmorefrequentlyifthewaterin the surfaceoccasionallytogulpair. Suchfish Some fishthatliveinstagnantpoolscometo affected ifoceantemperatures weretoincrease. carbon dioxideintheatmospherewouldbe solved inoceanwater. Explainhowthelevelof things andbytheburningoffossilfuelsisdis- Much ofthecarbondioxideproducedbyliving 11 How doyourresultscomparewiththepredictionsofhypothesis? CHEMISTRY SMALL-SCALELABORATORY MANUAL Based onyourresults,whatcanyouinferabouttheeffect of 3. overnight? Explain. opened thanonethathasbeenrefrigerated perature morelikelytobubbleoverwhen Is abottleofcarbonatedbeverageatroomtem- aeClass Date Chemistry Small-Scale LaboratoryManual

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. H Specific HeatofMetals Chemistry Small-Scale LaboratoryManual 5. 4. 3. 2. 1. Pre-Lab Safety Precautions of metals? measure thespecificheat How canyouusewaterto Problem Name amount ofheattransferhaveahighspecificheat. Objects thatexperienceasmalltemperaturechangeforgiven absorb orreleaseagivenamountofheathavelowspecificheat. of. Objectsthatexperiencealargetemperaturechangewhenthey temperature changedependsinpartuponwhateachobjectismade temperature ofthecoolerobjectincreases.Themagnitude Specific HeatofMetals hypothesis onpage46. its mass.Explainyourreasoning. Recordyour cause thelargest changeinwatertemperaturefor hypothesis aboutwhichof thethreemetalswill Read theentirelaboratoryactivity. Forma an insulatingmaterial? Why isitimportantthatacalorimeterbemadeof What isacalorimeter? is thespecificheatofsubstanceX? temperature fallsfrom45.1 When thesamplereleases795Jofheat,its sampleofsubstanceXhasamass123g. A Define LAB the temperatureofwarmerobjectdecreasesand eat flowsfromawarmerobjecttocoolerobject.Asheatflows, specific heat 12 LABORATORY MANUAL CHEMISTRY SMALL-SCALE . ¡ C to17.6 • • • • • • Objectives • • of eachmetal. Calculate Measure Construct warmer metalsareadded. the calorimeterwhen temperature ofwaterin Wipe upanywaterspillsimmediatelytoavoidslipping. Avoid spillingwateronthehotplatepowercord. Use cautionandproper protection whenhandlinghotobjects. Broken glassware mayhavesharpedges.Becareful whenusingscissors. Always wearsafetygoggles,gloves,andalabapron. ¡ C. What changes inthe the specificheat a calorimeter. 4. 3. 2. 1. Procedure the bottomofcalorimeter. and setitontopoftheothercup,whichwillbe cup willbethetopofcalorimeter. Invertit each tube. Place eachmetalinaseparate testtube,andlabel nearest 0.1g.Recordthemasses in Measure themassofeach metal sampletothe keep itfromtippingover. Place thecalorimeterinoneofbeakersto enough toholdthethermometer. top ofthecalorimeter. The holeshouldbelarge Use apenciltopunchholeinthecenterof the plastic-foamcups. As shownin Use scissorstoremovethelipfromoneof aeClass Date 100-mL graduated 400-mL beakers(2) plastic-foam aluminum, iron, Materials cylinder cups (2) and leadsamples test-tube rack thermometer hot plate balance scissors boiling chips large testtubes(3) Figure A, Data Table1. this 45 46 Figure B Figure A Name 9. 8. 7. 6. 5. LAB column foraluminum. the initialwatertemperatureindatatable the samefor3min.Recordthistemperatureas perature ofthewatereveryminuteuntilitstays the topofcalorimeteroff, measurethetem- Pour thecoldwaterintocalorimeter. With volume inthedatatablecolumnforaluminum. the volumetonearest0.1mL.Record cold waterintothegraduatedcylinder. Measure of While thewaterisheating,pourabout75mL to aboil. plate. Turn thehotplateonandheatwater Set thebeakerofwaterandtesttubesonhot water togetintothetesttubes. to thebeakerifnecessary, butdonotallowany the topsofmetalsamples. Add morewater Be surethewaterlevelinbeakerisabove tubes inthebeaker, asshownin chips tothesecondbeaker. Placeallthreetest ofwaterandafewboiling Add about300mL 12 IHLOW HIGH MED OFF CHEMISTRY SMALL-SCALELABORATORY MANUAL Beaker Intact cup Cup withlipremoved Hole incup Thermometer Hot plate Metal sample Beaker ofwater Test tube Figure B. 13. 12. 11. 10. Cleanup andDisposal Hypothesis 15. 14. 5. 4. 3. 2. 1. aluminum. temperature inthedatatablecolumnfor temperature attainedbythewaterasfinal hit thethermometer. Recordthehighest temperature. Donotallowthemetalsampleto calorimeter for30swhileyoumonitorthe Gently swirlthebeakercontaining touches thebottomofcalorimeter. calorimeter topuntilthetipofthermometer Insert thethermometerthroughholein in thecalorimeterwithoutsplashing. Carefully slidethealuminumintowater that containsthealuminumsample. Use thetest-tubeholdertoremovetesttube water boiling. the datatablecolumnsforeachmetal.Keep temperature astheinitialmetalin the sametemperatureaswater. Recordthe You canassumethatthemetalsamplesareat measure thetemperatureofboilingwater. After thewaterhasbeenboilingfor10min, detergent beforeyouleavethelab. Wash your handsthoroughlywithsoapor their properplaces. Return themetalsamplesand labequipmentto condition asyoufoundit. Make sureyourbalanceisleftinthesame Dry themetalsampleswithapapertowel. has cooled,pouritdownthedrain. Turn off thehotplate. After theboilingwater lead samples. Repeat steps8,9,and11 calorimeter. Pourthewaterdowndrain. Remove thealuminumsamplefrom put thetoponcalorimeter. aeClass Date Chemistry Small-Scale LaboratoryManual Ð 14 fortheironand CAUTION: Quickly

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 1. Analyze andConclude 4. 3. 2. 1. Data andObservations Name Specific heat,J/(g Heat gainedbywater(J) Change inmetaltemperature( Change inwatertemperature( Final temperature( Initial metaltemperature( Initial watertemperature( Volume ofwater(mL) Mass ofmetal(g) LAB the surroundingsinthisexperiment.) factors determinewhetherthisassumptionisvalidor not?(Hint:Identifythesystemand amount ofheatlostbythemetalequals heatgainedbythewater. What Applying Concepts amount ofheatgainedbythewater.) Recordtheresultsin to solveforspecificheat,andassumethattheamountofheatlostbymetalequals Use thesameequationtocalculatespecificheatofeachmetal.(Rearrange water is1.00g/mL.)Recordtheresultsin by thewaterfromeachmetal.(To determine themassofwater, assumethedensityof Use theequationinSection16.1ofyourtextbooktocalculateamountheatgained the initialmetaltemperature.Recordresultsin Calculate thechangeineachmetal water temperaturefromthefinaltemperature.Recordresultsin Calculate thechangeinwatertemperaturecausedbyeachmetalsubtractinginitial 12 ° C) ° C) CHEMISTRY SMALL-SCALELABORATORY MANUAL To calculateeachmetal ° ° C) C) ° ° C) C) ’ s temperaturebysubtractingthefinalfrom lmnmIo Lead Iron Aluminum Data Table1. Data Table 1 ’ s specificheat,youassumedthatthe Data Table1. Data Table1. aeClass Date Data Table1. 47 48 4. 3. 2. Name Real-World Chemistry 2. 1. LAB with thevaluesgivenin experience agivendecreaseintemperaturepergramofmetal?Explain. Explain possiblesourcesoferrorinthelab. mass ofthemetal.Useresultsthiscalculationtoevaluateyourhypothesis. Observing andInferring Drawing aConclusion Error Analysis Why? pan inthesameovenwithyourbarehands. burn yourselfifyoutouchathickaluminum out burningyourself.However, youwillsurely foil fromahotovenwithyourbarehandswith- It ispossibletoremoveasheetofaluminum mass.) ture of37 (Assume thesinkershaveastartingtempera- heats ofthesemetalstoexplainyouranswer. iron orlead?Useyourdataonthespecific water morequicklyifthesinkerwasmadeof covered lakereachthetemperatureof Would afishingsinkerdroppedintoanice- 12 ¡ C andhavethesameshape Compare thespecificheatsyoucalculatedforaluminum,iron,andlead CHEMISTRY SMALL-SCALELABORATORY MANUAL Table 16-2 For eachmetal,dividethechangeinwatertemperatureby Which ofthesemetalsmustreleasethemostheatto of yourtextbook.Calculatethepercenterrorifany. 3. would notrequireanyadditionalequipment. suggest amethodforidentifyingthemetalthat fragment? Explainwhyornot.Ifnot, alone beenoughtoidentifythemetalin heat of0.129J/(g Suppose afragmentisfoundtohavespecific measure thespecificheatoffragments. fragments foundatthesiteofanexplosionisto One waytoidentifythecompositionofmetal aeClass Date Chemistry Small-Scale LaboratoryManual ¡ C). Would thisinformation

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Physical Processes Energy ChangesinChemicaland Chemistry Small-Scale LaboratoryManual 2. 1. Pre-Lab Safety Precautions spontaneous? physical processis whether achemicalor How canyoudetermine Problem Name in which ( processes arespontaneous. this activity, youwilldeterminewhethersomechemical andphysical spontaneous onlyathigherorlowertemperatures,respectively. In spontaneous if of thesystem( spontaneous ornotdependsuponwhetherthechangeinenthalpy disorder, ofthesystemmayincreaseordecrease.Whetheraprocessis W Physical Processes Energy ChangesinChemicaland H S Is and processes. Contrast exothermicandendothermic reactions process? Inan endothermicprocess? system system LAB H be absorbedorreleasedbythesystem,andentropy, or hen achemicalorphysicalprocessoccurs,heat(enthalpy)may system ) arepositiveornegative.Aprocessisalwaysspontaneousif is negativeand H system 13 positive ornegativeinanexothermic H H and system system LABORATORY MANUAL CHEMISTRY SMALL-SCALE ) andthechangeinentropyofsystem S is positiveand system S system • • • • • • • • Objectives • are bothpositiveornegative tem duringtheprocess. temperature ofeachsys- Deduce Observe Calculate physical process. and afterachemicalor of foursystemsbefore Measure process isspontaneous. process. that occurduringeach Never placeapipetteinyourmouth. Do notdisposeofwastesinthesinkortrashcan. Notify yourteacherofanyspills. Use extracare whenhandlingallchemicals. Always wearsafetygoggles,gloves,andalabapron. is positive,whereasaprocessnever whether each physical changes the temperature the changein S system is negative.Processes 3. a solution? system whenasolidorliquid dissolvestoform What usuallyhappenstothe entropyofa aeClass Date 6 thin-stem 24-well microplate NaHCO NH Materials M pipettes (2) 4 HCl Cl(s) 3 (s) toothpicks (1box) distilled water scissors thermometer 49 50 from thetemperatureafter mixing.Recordtheresultsin Calculate thetemperature change ineachwellbysubtractingthetemperaturebefore mixing Data andObservations Figure A Procedure Name 2. 1. 5. 4. elCnet iigmxn change( mixing NH mixing NaHCO B1 NH A2 Contents A1 Well 2NaHCO B2 LAB Cut bulbhere. positive ornegative? shown in to cutoff theendofbulb ofapipette,as Make achemicalmicroscoopbyusingscissors ture in are atroomtemperature.Recordthistempera- of thechemicalsyouwilluseinthisexperiment of theairinroom. You mayassumethatall Use athermometertomeasurethetemperature Is aprocessspontaneouswhen ( equation thatrelatesfreeenergy change Read theentirelaboratoryactivity. Write the Thin-stem pipette G system 13 Data Table1. ), Figure A. 4 4 Cl Cl 3 H 3 system H HCl H HCl 2 O 2 O CHEMISTRY SMALL-SCALELABORATORY MANUAL , S system eoeAtrTemperature After Before , andtemperature. Temperature ( G system is ° Data Table 1 C) Data Table1. 10. Cleanup andDisposal 9. 8. 7. 6. 5. 4. 3. 3. 2. 1. each ofwells A2 andB2onthemicroplate. changes youobserve. Add ahalfpipetteof6 Add ahalfpipetteof6 Repeat steps6and7. Add ahalfpipetteofdistilledwatertowell A2. Rinse thethermometerincoldwater. ature in temperature ofthemixture.Recordtemper- Stir themixturewithatoothpick.Measure distilled watertowell A1. Use theotherpipettetoaddahalfof Place ahalfmicroscoopofsolidNaHCO Place ahalfmicroscoopofsolidNH detergent beforeyouleavethe lab. Wash yourhandsthoroughlywithsoapor Return alllabequipmenttoitsproperplace. directed byyourteacher. Dispose ofallchemicalsandsolutionsas of wells A1 andB1onthemicroplate. Repeat steps6and7. Repeat steps6and7. aeClass Date ° )Observations C) Data Table1. Chemistry Small-Scale LaboratoryManual M M Also recordanyphysical HCl towellB2. HCl towellB1. 4 Cl ineach 3 in

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 5. 4. 3. 2. 1. Analyze andConclude Name Real-World Chemistry 2. 1. LAB about thephysicalchangethatoccurredineachprocess.) exothermic. Drawing aConclusion Observing andInferring Applying Concepts Classifying Thinking Critically temperature beforetheyweremixed? spontaneous ( any, istheconversionofgraphitetodiamond made ofpurecarbon.Underwhatconditions,if spontaneous at25 alternative fuel.Isthecombustionofbenzene Benzene canbeaddedtogasolinemakean abrasives andcuttingtools.Bothdiamond( elry andarealsousedinindustrytomake Diamonds arehighlyvaluedasgemsforjew- reaction, 439.1 J/K. 2.4 J/K)andgraphite( 13 H Classify theprocessthatoccurredineachwellasendothermicor system H system ¡ CHEMISTRY SMALL-SCALELABORATORY MANUAL C? Inthecombustion Why isitvalidtoassumethatallchemicalswereatroom Is 6535 kJand Under whatconditionswilleachprocessoccurspontaneously? S H Is for eachprocesspositiveornegative? 1.90 kJ)?Explain. S 5.7 J/K)are for eachprocesspositiveornegative?(Hint: Think S system S 3. solid NH izer andexplosives.Undertherightconditions, a startingmaterialinthemanufactureoffertil- the decompositionreaction, Ammonia (NH spontaneously? (Hint: Assume temperature atwhichthereactionwilloccur kJ and 0.1 kJatthattemperature.) aeClass Date S 4 Cl decomposesintoNH system 3 ) isusedasarefrigerantand 285 J/K. What isthelowest H system G 3 system and HCl.In 176 51

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. C Determining ReactionOrders Chemistry Small-Scale LaboratoryManual sodium hydroxide? between crystalvioletand equation forthereaction What isthegeneralrate Problem Name equation betweentheacidicformofcrystalviolet(CV in basicsolutions.Thecolorchangeisrepresentedbythechemical identifications isthatitblue-violetinacidicsolutionsandcolorless CV determined experimentally. the concentrationdoubles.Values forthesuperscriptsmustbe concentration doubles,andavalueof2meanstheratequadruplesas affect thereactionrate.Avalueof1meansratedoublesas for experimentally withvaryingconcentrationsofreactants, thevalues be usedtocalculatetherateofreaction.Bydetermining therate the solutionbecomescolorless.Thetimeandconcentration datawill concentration. represent therelationshipbetweenrateandreactant the followingforminwhichsuperscriptsarewholenumbersthat rate-limiting, stepinthereaction. the sloweststep.Therefore,ratelawdescribesslowest,or reactions takeplaceinaseriesofsteps,thereactionratedependson is affected bychangesinreactantconcentrations.Becausechemical per unitoftime.Thegeneralratelawindicateshowthereaction Rate isusuallyexpressedasthechangeinconcentrationofareactant Determining ReactionOrders LAB m In thisactivity, youwillmeasurethetimeneededfor thecolorof If thesuperscriptisequaltozero,concentrationdoesnot The generalratelawforthereactionbetweenCV Rate isthechangeinanymeasurablepropertyperunitoftime. identifying bacteria.Onereasoncrystalvioletisusedforthese rystal violetisabiologicalstainthatusedinfingerprintingand to disappearasCV and n 14 in thegeneralratelawcanbedetermined. C 25 blue-violet (CV H 30 N LABORATORY MANUAL CHEMISTRY SMALL-SCALE 3 Cl Rate – OH isformed.Thereactioncompletewhen NaOH • • • • Objectives k data. tion fromexperimental cal reactions. Determine Infer Compare for reactionstooccur. Measure experimental data. order ofreactionfrom [CV colorless(CV ) 0 general rateequa- ] C n 25 [NaOH] the timeneeded rates ofchemi- H a valueforthe 30 N 3 m OH – OH) NaCl ) andNaOH. and NaOHhas aeClass Date 1.0 2.0 Materials droppers (3) 24-well microplate violet solution with deepwells solution M NaOH 10 4 M crystal distilled water toothpicks (3) stopwatch orclock sheets ofwhite with secondhand paper (15) 53 54 Data andObservations 2. 1. Procedure 5. 4. 3. 2. 1. Pre-Lab Safety Precautions Name ecinmxueCytlvoe dos 0.1 Crystalviolet(drops) Reaction mixture LAB reaction? participates intherate-limitingstepof amount ofcrystalvioletindicatedin Using thethirddropper, addtheappropriate wells byreactionnumber. Use aseparatedropperforeachliquid.Labelthe NaOH intheproportionslisted paper. Inthreeseparatewells,mixthewaterand Set a24-wellmicroplateonsheetofwhite hypothesis astothevaluesof experiments totesttheirhypotheses.Forma dict whattheratelawmightbe. Then theyrun of howchemicalsreactwithoneanothertopre- anced chemicalequationandpreviousknowledge Read theentirelabactivity. Scientistsusethebal- concentrations. not calculatedusingthesodiumhydroxide Explain whythevalueofaveragerateis white sheetofpaper? What isthepurposeofplacingwellplateona How canyoutellwhenthereactioniscomplete? What isthelikelyvalue(s)of hypothesis inthenextcolumn. eral ratelawforthisexperiment.Recordyour Table 1 015 10 5 332072 15205 14 for reaction1. CHEMISTRY SMALL-SCALELABORATORY MANUAL • • • • m m When waterandNaOHare mixed,muchheatisreleased. NaOH iscorrosive. Crystal violetismoderatelytoxicandatissueirritant. Always wearsafetygoggles,gloves,andalabapron. if the[NaOH] and Data Table1. n Data in thegen- Data Table 1 M aH(rp)Dsildwtr(rp)Time(s) Distilledwater(drops) NaOH (drops) 6. 5. 4. 3. 4. 3. 2. 1. Cleanup andDisposal Hypothesis Repeat steps2to5forreactionmixturesand3. disappear in the numberofsecondsittookforcolorto As soonasthesolutionbecomescolorless,record solution iscolorless. stirring untilthebluecolordisappearsand Stir themixturewithatoothpick.Continue the crystalviolet. Check thetime(orsetstopwatch)asyouadd detergent beforeyouleavethelab. Wash yourhandsthoroughlywithsoapor teacher. Dispose ofallsolutionsasdirectedbyyour Return alllabequipmenttoitsproperplace. Wash, dry, andstoreallglassware. aeClass Date Chemistry Small-Scale LaboratoryManual Data Table1.

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 5. 4. 3. 2. 1. Name LAB which thevaluesfor[CV entries inthecalculationstable.Readinghorizontally, identifythereactionmixturesfor solution. Forreaction#1:2 the numberofdropsused,anddividebytotalsolution. Record thisvaluein the logarithmofbothsides. for [NaOH]change,butthevalues[CV tion entriesinthecalculationstabletoidentifyreaction mixturesforwhichthevalues Determine theorderofreactionwithrespectto[NaOH]. Examinetherateandconcentra- To findthevalueof reduces tothefollowing. The valuesfortherateconstantand[NaOH]aresameinbothreactions,soratio Determine theorderofreactionwithrespectto[CV ing equation. to bezeroattheendofreaction,soaverageratecancalculatedfromfollow- Calculate theaveragerateforeachreaction. The acidicformofcrystalvioletisconsidered To determinetheconcentrationofNaOH,multiplyoriginal(1.0 (2 To determinetheconcentrationsofcrystalviolet,multiplyoriginalconcentration substitute theappropriatevaluesintofollowingratio. The letters number ofthereactionmixture. number ofthereactionmixture. priate valuesintothefollowingratioandsolvefor ecinmxueCrystalviolet( Reaction mixture 10 14 4 3 2 1 M ) bythenumberofdropsused,anddividetotal n Data Table2. CHEMISTRY SMALL-SCALELABORATORY MANUAL [CV , theorderofreactionwithrespecttocrystalviolet,you musttake ] changebutthevaluesfor[NaOH]staysame. Then Rate ] Rate log final log Rate Rate 10 time x z Rate Rate x z 4 Rate Rate [CV M [CV [CV x z x z k k [CV [CV 5 drops/(30dropssolution) ] initial ] ] M z n x n m NaOH( ) Data Table 2 n ] ] z n x n log log ] staythesame. Then substitutetheappro- [NaOH] [NaOH] 0 m [CV [CV . The letters . The [NaOH] [NaOH] [CV [CV ]. Examinetherateandconcentration [CV time ] ] z m x m x z ] ] x z n x z aeClass Date ] initial x and M x ae( Rate ) and z 3.33 represent the z represent the 10 M 5 ) by M . M /s) 55 56 3. 2. 1. Analyze andConclude 6. Name Real-World Chemistry b. a. amount ofwaterpresent. doubles whentheconcentrationofethylacetate butisunaffected bythe HCl isaddedasacatalyst,theratequickenssignificantly. Suppose therateofreaction lowing reaction. The rateofthisreactionismuchtooslowtobemeasured,but when Ethyl acetatereactswithwatertoformaceticacidand ethanolaccordingtothefol- LAB differed, calculateyourpercent errorindeterminingthevaluesoftwoexponents. law? Rate Interpreting Data to thefollowingchemicalequation.Howcanyouaccountforabsenceof[I chemical reactionstudied. Acetone isiodinatedinthepresenceofsulfuricacidaccording Thinking Critically superscripts Write thegeneralratelawforthisreaction,substitutingyourcalculatedvalues sources oferrororimprecisionwiththisexperiment? Error Analysis rate lawfortheacid-catalyzed reaction. catalystincreasesthe reactionratebychangingtherate-limitingstep.Suggest a A Write thegeneral rate lawfortheuncatalyzedreaction. 14 m [acetone] CH and ty ctt ae ctcai ethanol aceticacid water ethyl acetate 3 C(O)OC Consider thatthevaluesforeachexponentshouldbe1.Ifyour n . CHEMISTRY SMALL-SCALELABORATORY MANUAL Your valuesfor generalratelawdescribesthechemistryofsloweststepin A 1 [HCl] 2 H 5 1 H 2 m O and 0 n CH may notbewholenumbers. What aresome 3 C(O)OH aeClass Date C 2 H 5 OH Chemistry Small-Scale LaboratoryManual 2 ] intherate

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. S Observing Equilibrium Chemistry Small-Scale LaboratoryManual Safety Precautions ions affect equilibrium? concentration ofreactant How dochangesinthe Problem Name FeSCN that moreFeSCN color stronglyresemblingtheofFeSCN precipitation ofFe(OH) color ofthesolutionbecomesmorelikereactants. Fe(NO are addedandwhenprecipitatesformed. mixture ofthefollowingchemicalsystemchangeswhencommonions observing colorchangesasthesystemisdisturbed. products havedifferent colors,shiftsinequilibriumcanbefollowedby reform reactantparticlesandrestoreequilibrium.Ifthereactants particles areremoved,theproductsreactinreversereactionto more products,thusrestoringtheequilibriumratio.Similarly, ifreactant system, theequilibriumisdisturbedandsystemrespondsbymaking of thereactantsisconstant.Ifmorereactantparticlesareaddedto certain ratiooftheconcentrationsproductsto Observing Equilibrium LAB The numberofFe In thisactivity, youwillobservehowthecolorof equilibrium completion. Instead,theyreachapointofequilibriuminwhich ome chemicalsystemsarereversible;thatis,theydonotgoto 3 2 ) 3 rnII o hoynt o iron(III)thiocyanateion thiocyanateion Iron(III) ion ions decomposetoformmoreFe is addedtothereactionmixtureatequilibrium.Thismeans Fe 15 3 2 ions willform,andthereactionmixturehavea LABORATORY MANUAL CHEMISTRY SMALL-SCALE 3 3 ions presentinsolutionwillincreaseifsolid reduces thenumberofFe • • • • Objectives • librium. direction ofshiftinequi- tant concentrationtothe Relate Observe equilibrium. associated withshiftsin SCN AgNO NH Always wearsafetygoggles,gloves,andalabapron. 4 SCN produces cyanidefumeswhenincontactwithacids. 3 changes inreac- is toxicbyingestionand will stainskinandclothes. color changes 3 3 ions andSCN 2 3 ion. Similarly, the ions insolution,so FeSCN aeClass Date distilled water KCl NH Fe(NO 0.1 0.1 Materials 0.1 1.0 2 ions. The M M M M 4 SCN AgNO NaOH KSCN Fe(NO 3 ) 3 3 3 ) 3 test-tube rack stirring rod medium testtubes droppers (2) grease pencil 10-mL graduated (7) cylinder (2) 57 58 Data andObservations Procedure Pre-Lab Name 4. 3. 2. 1. 5. 4. 3. 2. 1. usac Color FeSCN KSCN Fe(NO Substance LAB Co(H common ion. following equilibriumsystem.Identifythe five testtubeslabeled1 or5m ofthis Pour 5mL withwater. Dilute themixturetoabout60mL FeSCN solution. Recordthecolorof Pour theKSCNsolutionintoFe(NO of 0.1 In asecondgraduatedcylinder, measure4mL the colorofFe 0.1 of Using agraduatedcylinder, measure4mL hypothesis inthenextcolumn. added tothereactionmixture.Recordyour for thisexperimentwhenpotassiumchlorideis the directionofshiftinequilibriumsystem Read theentirelaboratoryactivity. Hypothesize (right)? the reactants(left)ortowardproducts Will theequilibriuminquestion3shifttoward One milliliterof0.1 tion, whatisthecolorofresultingmixture? When apinksolutionismixedwithbluesolu- reaction occursandaprecipitateforms? tion changewhenadouble-replacement How dotheconcentrationsofionsasolu- SCN M 3 2 ) 3 15 2 ion M Fe(NO O) ion in 2 KSCN solution.Recordthecolorof 6 2 ion in 3 Data Table1. ) 3 Data Table 1 4Cl solution intoatesttube.Record Data Table1. diluted 3 CHEMISTRY SMALL-SCALELABORATORY MANUAL M ion in 3 HCl isaddedtothe Co(H Ð 5. solution intoeachof Data Table1. 2 O) 2 Cl 4 2 3 ) 3 4H 2 O Hypothesis 10. Cleanup andDisposal 9. 8. 7. 6. 5. 3. 2. 1. Table 2 librium, andtheidentityofanycommonion. the reactants,directionofshiftinequi- whether thiscolorisliketheproductsor solution. Stirtomix. To testtube#5,add10dropsof0.1 solution. Stirtomix. To testtube#4,add3dropsof1.0 To testtube#3,add0.5gKCl.Stirtodissolve. To testtube#2,add0.5gNH To testtube#1,add0.5gFe(NO For eachstep6through10,recordin detergent beforeyouleavethe lab. Wash yourhandsthoroughlywithsoapor Return alllabequipmenttoitsproperplace. teacher. Dispose ofallsolutionsasdirectedbyyour dissolve. dissolve. aeClass Date the colorofsolutionafterstirring, Chemistry Small-Scale LaboratoryManual 4 SCN. Stirto 3 ) M 3 M . Stirto NaOH Data AgNO 3

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 3. 2. 1. Analyze andConclude Name ettb itrigCommon disturbing Test-tube ubreulbiminaddClratrsirn ecat rdcsLf Right Left Products Reactants Colorafterstirring ionadded equilibrium number LAB equilibrium mixturewhenyouaddedNaOHandaprecipitateformed? The precipitateformedafteradding AgNO Fe system, didtheequilibriumshiftinsamedirectionasitshiftedforcommonion decrease thereactantconcentrations?(Hint: When theKClwasaddedtoequilibrium Observing andInferring Observing andInferring Observing andInferring 3 50.1 0.5gKCl 41.0 0.5gNH 3 0.5gFe(NO 2 1 ?) 15 Substance M M AgNO NaOH 4 SCN CHEMISTRY SMALL-SCALELABORATORY MANUAL 3 3 ) 3 Was areactantionorproductremovedfromthe Use yourdatatosupportorrefutethefollowingstatement. Based onobservations,didtheadditionofKClincreaseor 3 removed SCN Data Table 2 ion ratherthanFeSCN aeClass Date oo sms ieshiftstoward Color ismostlike 2 ion. Equilibrium 59 60 4. Name Real-World Chemistry 1. LAB equilibrium shiftswhen b. a. Predicting obtained. lated tomaximizetheamountofammonia how theconditionsofreactionaremanipu- process forammoniasynthesisandinvestigate industrial chemistry. LookuptheHaber the desiredproductisasignificantpartof Manipulating anequilibriumsystemtoachieve reactant ionsareaddedtothesolution. reactant ionsareremovedfromsolution. 15 Examine CHEMISTRY SMALL-SCALELABORATORY MANUAL Data Table2 and thenwriteasentencetodescribehowthe 2. H following equation:CO acid thatdissolvesinwateraccordingtothe Bottled carbonatedbeveragescontaincarbonic equilibrium? the escapingcarbondioxidegashaveon equilibrium isdisturbed. What effect does 2 CO aeClass Date 3 (aq). When abottleisunsealed, the Chemistry Small-Scale LaboratoryManual 2 (g) H 2 O(l) 3

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. R Exploring ChemicalEquilibrium Chemistry Small-Scale LaboratoryManual 4. 3. 2. 1. Pre-Lab Safety Precautions the reactionproduct? uring theconcentrationof chemical reactionbymeas- equilibrium constantfora Can youcalculatethe Problem Name investigate thereactioninwhichcolorlessFe for thisreversiblereactionisFe combine toformredFeSCN increases withtheconcentrationofFeSCN defined bytheequilibriumconstant, relationship betweenthereactantandproductconcentrationsis Exploring ChemicalEquilibrium equilibrium? Explain. Explain. of Fe What effect woulddecreasingtheconcentration of Fe What effect woulddecreasingtheconcentration reaction betweenFe Write theequilibriumconstantexpressionfor the the reactionbetweenFe ria. Which typeofequilibriumisrepresentedby Contrast homogenousandheterogeneousequilib- LAB concentrations ofallreactantsandproductsareconstant.The eversible chemicalreactionsreachanequilibriuminwhichthe 3 3 have ontheequilibriumconstant? have ontheconcentrationofFeSCN 16 LABORATORY MANUAL CHEMISTRY SMALL-SCALE 3 and SCN 3 and SCN 2 • • Objectives • • Donotdisposeofmaterialstoberecycled inthesinkortrashcan. • Useextracare whenhandlingthesolutions. • Donotoperateapipettewithyourmouth. • Alwayswearsafetygoggles,gloves,andalabapron. • ions. Theintensityoftheredcolor the reactionbetweenFe concentration ofFeSCN equilibrium. Calculate Relate Estimate Prepare solutions atequilibrium. solution. 3 . (aq) ? K color-intensity valuestothe serial dilutionsofastandard eq the colorintensityof the equilibriumconstantfor SCN . Inthisexperiment,youwill 2 2 . Thenetionicequation 3 (aq) at and SCN 3 1. Procedure 5. 2 FeSCN 3 Table 1. Figure A. solution inwell A1 ofthemicroplate,asshown in Use apipettetoplace10dropsofFe(NO your hypothesisonpage62. in wells A1ÐA6. Explainyourreasoning.Record hypothesis abouthowthecolorintensitywillvary Read theentirelaboratoryactivity. Forma at and SCN aeClass Date ions 2 (aq). Record theFe . 0.200 Materials 2.00 0.6 sheet ofwhitepaper thin-stem pipettes(6) 24-well microplate M 3 M HNO 10 Fe(NO concentration in 3 3 M 3 KSCN ) 3 3 ) 3 Data 61 62 Data andObservations 4. 3. 2. Figure A Name el( Well A6 A5 A4 A3 A2 A1 LAB HNO well D6.Useasecondpipettetoadd10dropsof fully withthesecondpipette. you addedHNO table. (Hint: The concentration wasreducedwhen Add 10dropsofHNO A2. RecordtheFe Transfer 10dropsofthemixtureinD6towell Place another10dropsofFe(NO Record theFe Transfer 10dropsofthismixturetowell A3. that remainsinwellD6.Stirwithacleanpipette. 3 16 solution towellD6.Stirthemixturecare- iigmxn iigClreulbimeulbimequilibrium equilibrium equilibrium Color mixing mixing mixing eoeatratra tat at after after before [Fe M 3 )( ][Fe 3 3 concentration in solution.) 3 CHEMISTRY SMALL-SCALELABORATORY MANUAL concentration inthedata 3 M solution tothemixture 3 )( [SCN ] 3 Data Table1. ) 3 solution in M nest ( intensity ) [FeSCN ] Data Table 1 Hypothesis 7. 6. 5. 3. 2. 1. Cleanup andDisposal intensity valuesin 0 (noredatall)to1.00(well A1). Recordthe onascalefrom color ineachwellrow A microplate. Estimatetheintensityofred Place asheetofwhitepaperbeneaththe row A. Carefullystirthecontentsofeachwell. Add 10dropsofKSCNsolutiontoeachwellin in row A. Repeat step4untilyouhavefilledallsixwells detergennt beforeyouleave thelab. Wash yourhandsthoroughlywithsoapor Return alllabequipmenttoitsproperplace. teacher. Dispose ofallsolutionsasdirectedbyyour aeClass Date M )( 2 [SCN ] Chemistry Small-Scale LaboratoryManual Data Table1. M )( ][Fe M 3 ) ] K — eq

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 3. 2. 1. Analyze andConclude 7. 6. 5. 4. 3. 2. 1. Name LAB in equilibrium concentrationinwell A1 bythecolorintensityineachwell.Recordresults concentration ofFeSCN the sameforallwells.)Recordresultsin SCN Record theresultsin same orderofmagnitudemaybeconsideredprecise.) think theprocedurewasprecise?Explainwhyor not.(Hint: Values thatarewithinthe Collecting andInterpreting Data Applying Concepts Drawing aConclusion Calculate theequilibriumconstant, Calculate theconcentrationofFe Calculate theconcentrationofSCN Calculate theconcentrationofFeSCN Calculate theconcentrationsofFeSCN Calculate theconcentrationofSCN each well.)Recordtheresultsin Calculate theconcentrationofFe concentration ofFeSCN temperature? Remember that10dropsofKSCNsolutionwasaddedtoFe(NO Record theresultsin make thesecalculations,assumethatalloftheSCN well. Recordtheresultsin Data Table1. , andFe 16 3 in wells A2 CHEMISTRY SMALL-SCALELABORATORY MANUAL Data Table1. Data Table1. How wouldtheresultsdiffer iftheexperimentwasdoneatahigher 2 2 Did yourresultssupporthypothesis?Explain. Data Table1. at equilibriumfromtheconcentrationofFe at equilibriumfromtheconcentrationofSCN Ð A6. Recordtheresultsin Data Table1. 3 3 K in wells A2 in eachwellaftermixingwithKSCN.(Hint: eq in wells A2 in eachwellaftermixing.(Hint: The valuewillbe 2 Based onthevaluesyoucalculatedfor 2 , usingtheequilibriumconcentrationsofFeSCN in wells A2 , SCN Data Table1. Ð A6 atequilibrium.Subtractthe , andFe Ð A6 atequilibrium.Subtractthe Ð A6 atequilibrium.Multiplythe was consumedinthereactionthis Data Table1. 3 in well A1 atequilibrium. To aeClass Date 3 after mixing. after mixing. 3 ) K 3 eq solution in , doyou 2 , 63 64 4. Name Real-World Chemistry 1. LAB Error Analysis the levelofFe be usedinahometestkitformeasuring and laundry. ExplainhowKSCNcould concentrations theycandiscolordishes ions arenotahealthhazard,athigh ions intothewater. Although these of iron,whichcanslowlyreleaseFe Many homeshavewaterpipesmade 16 3 Explain possiblesourcesofimprecisionintheexperiment. in water. CHEMISTRY SMALL-SCALELABORATORY MANUAL 3 2. react toformethylacetate(CH increase theproductionofethylacetate? as itforms. What othersteps couldbetakento Explain whyitisimportanttoremoveethylacetate CH this reaction. used tomakeartificialsilk. Water isalsoproducedin Acetic acid(CH 3 COOH aeClass Date C 3 2 Chemistry Small-Scale LaboratoryManual COOH) andethanol(C H 5 OH 3 CH 3 3 COOC COOC 2 2 H H 2 H 5 5 ) whichis 5 OH) H 2 O

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Comparing theStrengths of Acids Chemistry Small-Scale LaboratoryManual 5. 4. 3. 2. 1. Pre-Lab Safety Precautions calculating their solutionsand by measuringthepHof strengths ofseveralacids Can youcomparethe Problem Name ionization constant, constant expression.Thevalueofthisexpression,calledtheacid ionization ofaweakacidcanberepresentedbyanequilibrium only partlyionizedatequilibrium.Likeotherreversiblereactions,the acids undergoessentiallycompleteionization,whereasweakare A Comparing theStrengths of Acids reaction: HA(aq) Write theequilibrium constantexpressionforthis solution andonthe centration ofaweakacidon thepHofacid hypothesis abouttheeffect ofdecreasingthecon- Read theentirelaboratoryactivity. Forma Define pH. Explain youranswer. Formic acidhasa Explain thedifference betweentheterms acid has a hypothesis onpage66. LAB cids ionizeandproducehydrogenionsinaqueoussolution.The strength ofanaciddependsonhowcompletelyitionizes.Strong and K a K of 1.8 dilute acid 17 a ? 3 10 K LABORATORY MANUAL CHEMISTRY SMALL-SCALE K K . a H a a of 1.8 , isameasureofthestrengthweakacid. 5 of theacid.Recordyour . Which acidisstronger? (aq) • • • • • • • Objectives • 10 solutions. standard anddiluted Rank each weakacid. Calculate Measure Prepare standard acidsolutions. strength. solution andthe concentration ofeach Do notdisposeofmaterialstoberecycled inthesinkortrashcan. Notify yourteacherofanychemicalspills. Use extracare whenhandlingthesolutions. Always wearsafetygoggles,gloves,andalabapron. A 4 (aq). . Acetic acid . Acetic the acidsinorderof serial dilutionsof the pHof the H weak K ion a of 4. 3. 2. 1. Procedure tration in A1. Recordthenameofacidandconcen- ture inwell A3 withthepipette. distilled waterinwell A3. Carefullystirthe mix- Transfer 2dropsofthesolutioninwell A2 tothe ture inwell A2 withthepipette. distilled waterinwell A2. Carefullystirthe mix- Transfer 2dropsof thesolutioninwell A1 tothe Place about20dropsof0.100 microplate. water ineachwellcolumns2and3ofthe Use apipettetoplace18dropsofdistilled aeClass Date 0.100 0.100 0.100 0.100 Materials distilled water pH papers(variousranges) thin-stem pipettes(12) 24-well microplate Data Table1. M M M M hydrogen peroxide(H citric acid(H boric acid(H permanganic acid(HMnO 3 3 C BO 6 H M 3 5 ) O boric acidinwell 7 ) 2 O 2 ) 4 ) 65 66 5. 4. 3. 2. 1. Data andObservations 6. 5. Name elAi [Acid]( Acid Well D3 D1 A3 A1 LAB C3 C1 B3 B1 Table 1. of acidandH Use theformulathatrelatespHand[H Calculate theaverage Calculate theacidionization constant, Subtract theconcentrationofH Calculate theconcentrationofacidinwells A1 Calculate theconcentrationofH wells A1 solutions ineachofthesewellsweremadebytwo10-fold dilutionsofthesolutionsin Calculate theinitialconcentrationofacidinwells A3 different pHrange.Recordthevaluesin indicate apHvalueforwell,trypaperwith in wells A1 Using pHpaper, measurethepHofsolutions different rowsofthemicroplate. oxide, andpermanganicacid.Placeeachacidin Repeat steps2 of acidatequilibriumiszero inanywell,drawadashthe acid.) Recordyourresultsin conjugate base, A 17 Ð D1.) Recordyourresultsin Ð D1 and A3 Ð in wells A1 4 withcitricacid,hydrogenper- , equalstheconcentrationof H CHEMISTRY SMALL-SCALELABORATORY MANUAL K Ð a D3. Ifapaperfailsto for eachacid.Recordyour resultsin Ð D1 and A3 Data Table1. ions atequilibriumfromtheinitialconcentrationof ions inwells A1 nta qiiru qiiru Average Initial equilibrium equilibrium Data Table1. K Ð a D3. (Hint:Rememberthat the concentrationof ].) Recordyourresults. , foreachacid,usingtheequilibrium concentrations M p ( )pH Data Data Table 1 Ð D1 and A3 .) Recordyourresults.Ifthe concentration Ð D1 and A3 Ð 3. 2. 1. Cleanup andDisposal Hypothesis D3. (Hint:Rememberthatthe [H detergent beforeyouleavethe lab. Wash yourhandsthoroughlywithsoapor Return alllabequipmenttoitsproperplace. teacher. Dispose ofallsolutionsasdirectedbyyour M Ð t [Acid]at ] at K D3 atequilibrium.(Hint: )( aeClass Date a Data Table1. Ð column forthatcell. D3 atequilibrium.(Hint: Chemistry Small-Scale LaboratoryManual M ) K a K a

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 3. 2. 1. Analyze andConclude Name Real-World Chemistry 2. 1. LAB can concludethattheacidinwellisastrongacid.Explainwhy. Indicate whethereachacidisastrongorweakacid. Drawing aConclusion Applying Concepts average error ifany. Explain possiblesourcesoferrorinthelab. Error Analysis grow inbasicsoil. Would itbeagoodideafor grow inacidicsoilandpinkflowerswhenthey hydrangeas produceblueflowerswhenthey produces large, roundclustersofflowers.Some The hydrangeaisapopulargardenshrubthat you studiedinthisactivity? of theseacidscomparewiththosethe of aminoacidsandDNA.Howdothestrengths mation. Lookuptheacidionizationconstants nucleic acidDNA,whichstoresgeneticinfor- which arelinkedtoformproteinsandthe Included are20different kinds ofaminoacids, which serveawidevarietyoffunctions. Your bodycontainsalarge numberofacids, 17 K a you calculatedforeachacidwiththeacceptedvalue.Calculatepercent Look uptheacceptedvalueof CHEMISTRY SMALL-SCALELABORATORY MANUAL If theconcentrationofacidatequilibriumiszeroinanywell,you Rank theacidsinorderofstrengthbasedonyourresults. K a for eachweakacid.Comparethe 3. Explain youranswer. wanted theplanttoproducepinkflowers? post madefromlemonandorangerindsifshe a gardenertofertilizehydrangeawithcom- learned aboutanhydrides.) Explain why. (Hint:Recallwhatyouhave fur oxidesandnitrogenintotheair. rain focusmainlyonlimitingthereleaseofsul- Government regulationsaimedatreducingacid ues andforwidespreadenvironmentaldamage. blamed forthecorrosionofbuildingsandstat- the normalvalueofabout5.5.Ithasbeen Acid rainisrainwaterthathasapHlowerthan aeClass Date 67

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Testing the Acidity of Aspirin Testingthe Acidity Chemistry Small-Scale LaboratoryManual 5. 4. 3. 2. 1. Pre-Lab Safety Precautions aspirin? buffered andunbuffered test thedifference between How canyouuseabaseto Problem Name common nameforacetylsalicylicacid(C pain relieverthatisdesignedtobegentleronthestomach. Therefore, manydrugcompaniesalsoproducebuffered aspirin,a acid, itcancauseanupsetstomachinsomepeoplewhouseit. A Testing the Acidity of Aspirin Testingthe Acidity Explain why. Recordyourhypothesison page70. smaller changeinpHwhen baseisadded. hypothesis aboutwhichpainrelieverwillshowa Read theentirelaboratoryactivity. Forma ume ofbaseadded? titration byexaminingagraphofpHversusvol- How canyouidentifytheequivalencepointofa buffer contain? acid (HA)dissolvedinwater. What elsemust the Suppose abuffer contains0.1moleofaweak What isabuffer? What happensinaneutralizationreaction? LAB spirin isamedicinethathasbeenusedforovercenturyto relieve pain,reducefever, andfightinflammation.Aspirinisthe 18 LABORATORY MANUAL CHEMISTRY SMALL-SCALE • • • • • • • Objectives for thetwopainrelievers. pH versusvolumeofbase a base. buffered aspirin. tions ofunbuffered and Make Titrate Measure Do notdisposeofmaterialstoberecycled inthesinkortrashcan. Notify yourteacherofanychemicalspills. Use extracare whenhandlingthesolutions. Always wearsafetygoggles,gloves,andalabapron. and each solutionwith the pHofsolu- 9 H use 8 O 4 a graphof ). Becauseaspirinisan 4. 3. 2. 1. Procedure dissolved. a stirringrod,stirthemixture untilthepowderis ofdistilledwatertothebeaker. Using Add 20mL beaker. the groundtablettoa50-mL unbuffered aspirinintoafinepowder. Transfer Using amortarandpestle,grindonetabletof in mark.Recordthisnumber cylinder tothe6.0-mL pipette tobringthewaterlevelingraduated number ofdropsthatmustbeaddedfromthe Fill apipettewithdistilledwater. Countthe reading atthebottomofmeniscus. graduated cylinder. Remembertotakethevolume ofdistilledwaterina10-mL Measure 5.0mL Data Table1. aeClass Date 0.1 Materials 10-mL graduated buffered aspirin unbuffered aspirin cylinder tablet tablet M NaOH plastic spoon distilled water pH paper stirring rod thin-stem pipettes mortar andpestle 50-mL beaker (3) 69 70 1. Analyze andConclude Data andObservations 10. Name 9. 8. 7. 6. 5. Buffered aspirin Unbuffered aspirin Number ofdrops in1.0mL: LAB Making andUsingGraphs each curve.Labelbothcurvesandaxes,give thegraphatitle. the dataforbothpainrelieversonsamegraph.Draw linesbetweenthedatapointsfor the beaker. Stirthemixture. NaOH. Recordyourresultsin of NaOH fromthepHafteradding5.0mL reliever bysubtractingthepHbeforeadding Calculate thechangeinpHforeachpain aspirin. Repeat steps3 ofNaOH. mL Repeat steps6and7untilyouhaveadded5.0 of NaOHadded. additional 1.0mL Record thepHindatatablecolumnforeach Measure thepHofsolutionwithpaper. of0.1 Use thepipettetoadd1.0mL Record thepHin Measure thepHofsolutionwithpaper. anrlee aH10m . L30m . L50m Change inpH 5.0mL 4.0mL 3.0mL 2.0mL 1.0mL NaOH Pain reliever 18 Ð 8 usingonetabletofbuffered Data Table1. pH before CHEMISTRY SMALL-SCALELABORATORY MANUAL Make agraphofpHversusvolumeNaOHadded. Plot Data Table1. M NaOH to Data Table 1 pH afteraddingNaOH 3. 2. 1. Cleanup andDisposal Hypothesis detergent beforeyouleavethe lab. Wash yourhandsthoroughlywithsoapor Return alllabequipmenttoitsproperplace. teacher. Dispose ofallsolutionsasdirectedbyyour aeClass Date Chemistry Small-Scale LaboratoryManual

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 4. 3. 2. Name Real-World Chemistry 1. LAB possible reasonsforanydisagreement. Collecting andInterpreting Data Making andUsingGraphs titrated toitsequivalencepoint?Explainyouranswer. Error Analysis (Hint: Referto Explain howcalciumcarbonateprotectsDNA. a mineralmadeofcalciumcarbonate(CaCO from destructioniftheareacontainslimestone, isprotected the tissues.However, theDNA in tissues, althoughitusuallydestroystheDNA slows thebreakdownofdeadorganisms Tannic acid,acompoundfoundinpeat bogs, after hundredsoreventhousandsofyears. organisms inpeatbogsthat are wellpreserved Scientists havediscoveredtheremainsofdead 18 Table 19-2 Compare theresultsofthisexperimentwithyourhypothesis.Explain CHEMISTRY SMALL-SCALELABORATORY MANUAL in yourtextbook.) Does yourgraphindicatethateitherpainrelieverwas Which painrelieverismoreacidic? ’ 3 ). 3. 2. but methanoicacidandwater.) residue? (Assumetheresiduecontainsnothing What isthemolarityofmethanoicacidin that isso? lenses areusuallybuffered. Why doyouthink Solutions soldforcleaningandstoringcontact of0.200 neutralized by42.0mL sampleofresidueis base. Supposea75.0-mL residue, chemistscantitratetheresiduewitha tration ofmethanoicacidintheprocess processing ofleather. To determine theconcen- Methanoic acid(HCOOH)isusedinthe aeClass Date M NaOH. 71

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Reduction ofManganese Chemistry Small-Scale LaboratoryManual Safety Precautions an oxidizingagent? unknown concentrationof agent beusedtofindthe tion containingareducing How canastandardsolu- Problem Name known concentration.ForKMnO before usetogettheirexactconcentrations.Aprimarystandardhasa oxalate, Na concentration ofKMnO solution, andthestoichiometryofbalancedchemicalequation, according tothefollowingequation: KMnO of anacid redox reactioninmuchthesamewaythatphenolphthaleinmarksend intense coloroftheseionsactsasanindicatorthatmarkstheend they containmanganeseatoms(Mn)withahighoxidationnumber. The oxidizing agent.Permanganateionsareexcellentagentsbecause 5H according tothefollowingreaction: solution turnsfaintpink.Thepermanganateionsreactwiththeoxalate A Reduction ofManganese 2 LAB C In thisactivity, ameasuredamountofNa This colorlesssolutionisheated,andKMnO From themassofNa 2 transfer ofelectronsbetweenreactantsidentifiesoxidation reactions. Areducingagentreleaseselectronsthatareacquiredbythe O 4 4 solutions havetobetitratedagainstaprimarystandardshortly (aq) – base reaction.But,becausepermanganateionsdecomposeeasily, 2 H 19 C 2 2 SO O 2KMnO 4 , inanaqueoussolutionofsulfuricacid. 4 (aq) LABORATORY MANUAL CHEMISTRY SMALL-SCALE 4 4 (aq) Na can bedetermined. 10CO 2 2 C • • • • • • • Objectives C 2 2 O molarity oftheKMnO tion Write try andvolumedata. solution usingstoichiome- Calculate 3H Never placeapipetteinyour mouth. Potassium permanganate istoxicandanirritant. Sodium oxalateistoxicand anirritant. Acids canbecorrosive. Handlewithcare. Always wearsafetyglasses,gloves,andalabapron. O 4 2 4 4 (s) 2 (g) , thevolumeofpotassiumpermanganate solutions, theprimarystandardissodium SO – reduction equations. 0 and 4 (aq) Na 8H a valueforthe balance 2 2 0 SO O(l) 2 4 C (aq) 2 4 O oxida- is addeddropwiseuntilthe 4 2MnSO is dissolvedinH 4 H 2 C 2 4 aeClass Date O (aq) 1.0 micropipettes (2) 10-mL graduated 100-mL beaker 0.1 gNa KMnO Materials 4 (aq). cylinder H M 2 SO solution of – K 4 reduction 4 2 solution 2 2 SO SO C 2 O 4 4 (aq). 4 distilled water stirring rod grease pencil hot plate test-tube rack test-tube holder thermometer test tubes(3) 73 74 Procedure Pre-Lab Name 5. 4. 3. 2. 1. 6. 5. 4. 3. 2. 1. LAB the H small amountofthesulfuric acidsolution.Put 1 milliliter.) Rinse thecalibratedH “ tube rack.Labelasecondsmalltest solid toatesttube,andsetthetubeintest- to thenearesthundredthofagram. Transfer the Measure andrecordthemassof0.10gNa tion, andtheendpointcannotbereached. causes theformationofamurkybrownsolu- 80 on ahotplateandheatthewatertobetween beakerto75mL.Setthe in the100-mL Prepare ahot-waterbath. Adjust thewaterlevel Label thispipette Repeat step1forthesecondmicropipette. number ofdropsin mark.Recordthe ated cylindertothe1.00mL gradu- number ofdropsneededtofilla10-mL one micropipettewithdistilledwater. Countthe beakerwithdistilledwater. Fill Fill a100-mL and NaC Hypothesize aboutwhatelementintheKMnO Na drops willbeneededtoreactwith0.10g KMnO Read theentirelaboratoryactivity. Ifthe ofKMnO Suppose that30.00mL electrons aretransferred? According tothebalancedequation,howmany MnO What istheoxidationstateofmanganesein redox reactionbetweenKMnO Write andbalancethenetionicequationfor “ process twomoretimes.Labelthispipette been dissolvedinH exactly reactswith0.250gofNa of theKMnO Partially fillthemicropipette with1.0 reduced. Recordyourhypothesisbelow. WASTE KMnO ¡ 2 C and90 C 19 4 2 2 O SO 4 ? InMnSO 4 4 solution isexactly0.04 2 . ? (Hint: There are24drops in ” 4 ” O andsetitinthetest-tuberack. rinse intothewastetesttube. 4 ¡ is oxidizedandwhatelement 4 C. Donotboilthewater. This solution. “ 4 H CHEMISTRY SMALL-SCALELABORATORY MANUAL ? Data Table1. 2 SO 2 SO 2 SO 4 . Calculatethemolarity 4 . 4 ” micropipette witha 4 M and H 2 4 , howmany C Repeat this solution 2 O M 4 2 C that has sulfuric 2 2 O C 4 2 . O 4 4 Cleanup andDisposal Hypothesis 10. 8. 7. 6. 3. 2. 1. 9. ring constantly. Add dropsofKMnO endpoint. it isthecolorofreactionmixtureat distilled water. This isyourtitrationstandard; and add1droptothetesttubecontaining KMnO ofthe the graduatedcylinderwith10mL drops in persist for30s.Recordthetotalnumberof color asthetitrationstandard. The colorshould added dropturnsthesolutionsamepink KMnO test tube.Partiallyfillthemicropipettewith water. RinsetheKMnO Fill athirdtesttubehalfwaywithdistilled graduated cylinderwithKMnO While thetesttubeiswarming,rinse10-mL 5 minutes. water bath. Allow thesolutiontowarmfor containing theacidicoxalatesolutioninto Using atest-tubeholder, placethetesttube detergent before youleavethelab. Wash your handsthoroughlywithsoapor Return alllabequipmentto itsproperplace. teacher. Dispose ofallchemicalsas directedbyyour add dropsofKMnO of thewaterbathabove65 After thecolordisappears,keeptemperature Using theKMnO test tubecontainingtheNa ofthisacidtothe acid solution,andadd2mL KMnO the KMnO solution. PuttheKMnO small amountofthepotassiumpermanganate (5 minutesorless). water bath.Stiruntilthecolordisappears in thewaterbath.Keeptesttube aeClass Date 4 4 4 solution fromthegraduatedcylinder, solution. rinse intothewastetesttube. Then fill Data Table2. Chemistry Small-Scale LaboratoryManual 4 solution intothetesttubewarming 4 micropipette, add3dropsof 4 one atatimewhilestir- 4 4 micropipette witha rinse intothewaste ¡ 2 C andcontinueto C 2 O 4 4 . Putthe . 4 until the

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 2. 1. Analyze andConclude 6. 5. 4. 3. 2. 1. Data andObservations Name Volume of KMnO Drops ofKMnO Mass ofsodiumoxalate(g) irppteue o:Til1Til2Til3Average Trial 3 Trial 2 Trial 1 H KMnO Micropipette usedfor: LAB occurs attheendpoint. Observing andInferring Observing andInferring Divide thenumberofmolesKMnO Using thebalancedchemicalequationandnumberofmolesNa Calculate thenumberofmolessodiumoxalate. Calculate themolarmassofsodiumoxalateandrecordin Data Table2. Multiply thedropsofKMnO number in Calculate theaveragenumberofdropsin1milliliterforyourmicropipettes.Recordthis Containing KMnO the numberofmolesKMnO question 2). This istheexact molarity, thestandardizedconcentration. per millilitertocalculatethevolumeofKMnO 2 SO 4 4 19 Data Table1. 4 needed toreachendpoint 4 needed toreachendpoint(mL) 4 ? Usethebalancednetionicequationtoinferwhy pinkcolor CHEMISTRY SMALL-SCALELABORATORY MANUAL Data Table 2 What isthepurposeofcalibratingmicropipette? What colorwasthesolutioncontainingH 4 needed toreachendpointbytheaveragenumberofdrops 4 used. 4 (from question5)bythevolumeofKMnO Data Table 1 4 solution used.Recordthisnumberin Number ofdrops in1mL aeClass Date Data Table2. 2 SO 2 C 4 2 and Na O 4 , calculate 4 2 C (from 2 O 4 ? 75 76 3. Name Real-World Chemistry 1. LAB Error Analysis b. a. reactions: lowing chemicalequationsdescribethesetwo to anynearbyoxidizablesubstance. The fol- HClO isformed,itreadilygivesupoxygen,O, when chlorinereactswithwater. Oncethe to thehypochlorousacid,HClO,thatisformed power. Chlorineowesitsbleachingcapability but totallydrychlorinehasnobleaching Chlorine isusedasableachanddisinfectant, reasoning. dizing agentorareducingagent?Explainyour HClO tobetheresultofitsactivityasanoxi- Would youexpectthebleachingactionof HClO Cl 19 2 0 H 2 O HCl 0 Explain possiblesourcesoferrorinthisactivity. CHEMISTRY SMALL-SCALELABORATORY MANUAL HCl O HClO 2. 2MnO Examine thecathodichalf-reaction: cathode inanalkalineflashlightbattery. of thepermanganateion.Itisalsopart Manganese dioxideisadecompositionproduct Is MnO cathode agent? Which processtakes placeatthe aeClass Date 2 (s) 2 — an oxidizingagentorareducing oxidation orreduction? Chemistry Small-Scale LaboratoryManual H 2 O(l) 0 Mn 2 O 3 (s) 2OH (aq)

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Plants Produce Oxygen Chemistry Small-Scale LaboratoryManual rate ofphotosynthesis? concentration affect the How doescarbondioxide Problem Name from methyleneblue. is usedasanindicator. Oxygengasistheonlythatremovescolor colorless andodorlessatroomtemperature pressure,methyleneblue photosynthesis oncarbondioxideconcentration. Becauseoxygengasis color changeoccurs,youcanqualitativelyevaluatethedependenceof oxygen, thecolorofsolutionchanges.Byobservinghowquickly carbon dioxideandwater. energy facilitatestheproductionofoxygenandcarbohydratesfrom from thered,blue,andindigowavelengthsofsunlight.Thelight energy source.Greenplants,algae,andsomebacteriaabsorbthe indicator anddifferent amountsofCO photosynthesis. monitoring itsproductionisanindirectmeasureoftheamount in thechloroplasts.Becauseoxygengasisaproductofphotosynthesis, of algaethenledscientiststohypothesizethatphotosynthesistookplace green chloroplastsinplantleaves.Oxygenproductionthe was obtainedfromtheredandbluewavelengthsoflightabsorbedby ecosystem requirescomplimentaryprocesses. exhales carbondioxideandwatervapor. To becomplete,thismini- investigators realizedthattheplantsproduceoxygen,whileanimal in anairtightjar, bothlived;butwhenkeptseparately, bothdied.Later, 1772. Heobservedthatwhenaplantandananimalwerekepttogether A Plants Produce Oxygen LAB In thisactivity, youwillpreparetwotestsamplescontaining an Researchers discoveredthattheenergyneededforphotosynthesis This conversionprocess,photosynthesis,wasobservedbyPriestleyin within agivenarea.Formostecosystems,sunlightistheultimate n ecosystemisthesumtotalofallorganismsandtheirenvironments 20 6CO 2 LABORATORY MANUAL CHEMISTRY SMALL-SCALE 6H 2 O • • Objectives • ------0 light energy chlorophyll photosynthesis. dioxide concentrationon dioxide concentration. production tocarbon Infer Relate Observe indicator. of oxygengasusingan enzymes the effect ofcarbon the rateofoxygen 2 the production . AsCO C 6 H 2 12 is consumedtoproduce O 6 6O aeClass Date 2 plastic weighing green leaves methylene blue 0.2% sodium Materials cup indicator solution solution ate (NaHCO hydrogen carbon- 3 ) light source distilled water test-tube rack stirring rod scoop orequivalent scissors small testtubes(3) micropipettes (2) 77 78 3. 2. 1. Procedure 4. 3. 2. 1. Pre-Lab Safety Precautions Name LAB shows therelationshipbetweenCO leaves toeachtesttube. solution. Besuretoaddthesamequantityof test tubefilledwithsodiumhydrogencarbonate of thetesttubesfilledwithdistilledwaterand Using ascoop,dividetheleafpiecesbetweenone pieces intheplasticweighingcup. small enoughtofitintothetesttubes.Collect Using thescissors,cutagreenleafintopieces blue solutiontoeachtesttube. it inthetest-tuberack. Add 3dropsofmethylene 0.2% sodiumhydrogencarbonatesolutionandset tube rack.Fillathirdsmalltesthalffullwith full withdistilledwaterandsetthetubesinatest- Using amicropipette,filltwosmalltesttubeshalf present? Explain. When methylenebluelosesitscolor, whatgasis water butnoleafpieces? What isthepurposeofatesttubewithdistilled function? are andwheretheyfound. What istheir Read abiologybooktolearnwhatchloroplasts of CO hydrogen carbonatedissolvedinwaterisasource Read theentirelaboratoryactivity. Sodium your hypothesisinthenextcolumn. photosynthesis tooccurmorerapidly. Record NaHCO Form ahypothesisastowhichsubstance 2 20 . The chemicalequationforphotosynthesis 3 or distilledwater CHEMISTRY SMALL-SCALELABORATORY MANUAL — • • • will cause Never placethepipetteinyourmouth. Methylene bluewillstainskinandclothing. Always wearsafetygoggles,gloves,andalabapron. 2 and O — 2 . 6. 5. 4. 3. 2. 1. Cleanup andDisposal Hypothesis cloudy.) (More entriesmaybeneededifthedayis 1-min intervalsuntilthesolutiondecolorizes. Record yourobservationsofthesolutionsat 0 min Record yourobservationsofthesolutionsin sunny windoworunderalamp. the liquid.) Then placethethreetesttubesina solution. (Leavesmayremainnearthesurfaceof Using astirringrod,mixtheleavesintoeach detergent beforeyouleavethelab. Wash yourhandsthoroughlywithsoap or Return alllabequipmenttoitsproperplace. teacher. Dispose ofallchemicalsasdirectedbyyour aeClass Date column of Chemistry Small-Scale LaboratoryManual Data Table1.

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual 3. 2. 1. Analyze andConclude Data andObservations Name Na Distilled water ouin0123456 5 4 3 2 1 0 Distilled water Solution LAB of photosynthesis? O of polymer ofglucosemoleculesthatwereformedduring photosynthesis.Suppose5mL Measuring andUsingNumbers Drawing aConclusion Observing andInferring (C collected at22.0 answer withevidencefromyourobservations. the photosynthesisequationwithformulaforglucose.) methylene blue methylene blue methylene blue 2 2 6 HCO gas isproducedduringaphotosynthesisexperiment similar tothisone.Ifthegaswas H 12 20 3 O solution 6 ) wasproduced?(Hint: leaf pieces ¡ C andabarometricpressureof754mmHg,whatmass ofglucose leaf pieces CHEMISTRY SMALL-SCALELABORATORY MANUAL What istherelationshipbetweenCO Which testtubebettersupportsphotosynthesis?Supportyour PV Starch isthestoragecarbohydrateinplants. a nRT ; replacethegeneralcarbohydrateformulain Data Table 1 Time elapsed(min) aeClass Date 2 concentration andtherate 79 80 5. 4. Name Real-World Chemistry 1. LAB be modifiedtocollectandmeasuretheamountofO Designing anExperiment/Identifying Variables Error Analysis to havegreenbeltsalongmajorfreeways? combustion offossilfuels. Why isitimportant community. Automobiles arepropelledbythe and othergreenerythatareplantedarounda Greenbelts arenarrowareasoftrees,shrubs, 20 Explain possiblesourcesoferrorinthisactivity. CHEMISTRY SMALL-SCALELABORATORY MANUAL 2 gas produced? 2. How couldtheexperimentaldesign might ithaveoverotherindicators? methylene bluebeincluded? What advantage blue initsformulation.Forwhatreasonwould oxygen infoodpackagingincludesmethylene ucts. Onepatentedindicatorfordetecting Oxygen promotesdeteriorationoffoodprod- aeClass Date Chemistry Small-Scale LaboratoryManual

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc. Chemistry Small-Scale LaboratoryManual Navta Associates: Art Credits CREDITS v, 6,18; Glencoe: 62; MacArt Design: 1, 2,14,18,22,34,38,42,46,50 81