HonorsChemistry
2016-2017
WS2.4Dimensional Analysis(FactorLabel)UsingStrange Units
1.Consider thefollowing: 3bushels=1 sack,4 pecks=1 bushel,2 gallons=1 peck.Ifthecostof agallonof apples equals$4.50, how muchwould20 sacksof applescost?(2160)
2.Priortometrication, woolweightwasmeasuredin unitslikecloves and stones. If1sack=2 weys,1 wey=6
½ tod,4 tod=2 stones,2 cloves=3 stone, and 1 clove=10 kilograms,answer thefollowing:
a.howmanystones do youhaveifyou have4 wey?(13)
b.Ifakilogramof woolhasacostof $4.00,howmuchwould15sackscostinBritishpounds?(The current exchangerateis approximately$1.20 perpound.)(2166)
Inearlier times,volume wassometimesmeasuredin strange units.Forexample:
1hogshead=2 barrels
9gallons=2 pin
2pottles=1 gallon
1puncheon=2 hogshead
1butt=2hogshead
2rundlets=4 firkins
1gill=4 fl. Ounces
10fl.Ounces=.08 gallon
1anker=10 gallons
3.Using the tableabove,howmanypuncheonaretherein7.5barrels.(1.875)
4.If10 gallonsofmilk weretocost$25.00,howmuchwould3000gillofmilk cost?(240)
5.Ifa youngtoddlercouldconsume 200fluid ouncesofmilkin 1day,howmanyankersofmilkcould the toddler consumeinoneweek?(1.12)
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HonorsChemistry
2016-2017
WS2.5MoreFactorLabel(Derived Units)
Directions:Usethefactor–labelmethod to make eachofthefollowingconversions.Referto appropriate tables for necessaryconversionfactors.
1)143milesperhourto meterspersecond.(63.9)
2)8.8feetpersecond tocentimeterspersecond.(268)
3)12.2 poundspercubicfoottokilogramsperliter.(0.196)
4)35.8gallonsperminute to literspersecond.(2.3)
5)46gramspercubic centimetertopoundspergallon.(383)
6)66.5kilometersperhour tofeetpersecond.(60.6)
7)8.2kilogramspercubic metertopoundspercubic foot.(0.51)
8)0.48centimetersperdaytoinches peryear.(69)
9)26kilogramsperlitertopoundsperquart.(54)
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HonorsChemistry
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WS2.6MoreFactorLabel
Directions:Use factor labelmethodtoconverteach of thefollowingtotheunit(s) requested.
1)Duringearlier timesinEngland,land wasmeasuredin unitssuch asfardells,nooks,yards,andkides.
2fardells=1nooke
4nookes=1 yard
4yards=1 kide a.Howmanykides aretherein 27fardells?(0.84)
b. Whatis theareaof land thatmeasures15fardells by12 kides?(5.625kidor5760fardell)
2)In1618,thePharmacopopoeiaofLondondefined thefollowingmassunits tobe usedin the preparationof drugs.
20grains=1 scruple
3scruples=1 drachma
8drachmas=1ounce
12ounces=1 pound a.Howmanygrainswerepresentin 16ounces?(7680)
b. Howmanypoundsweretherein78.16 drachmas?(0.8142)
3)Twodozendimeswillcreateastackof approximately1 inchinheight.Nickelsareas thickas1-¾dimes.
Howmanynickelswouldyouhaveifyour stackreached6 feet?(988)
4)Apopcornserver atSeaWorldknows thaton a busySaturday,shewillneed tofill thepopcorn warmer
53times.Thepopcornwarmerholds24bagsof popcorn.Theserveralso knowsthata20ounce scoop
ofunpopped popcornwillmake8bagsofpopcorn.Howmany50 lb. sacksof unpopped popcornwill the popcornserver need toorder? (4)
5)Walking burns 550Calories anhour.A bacon,egg and cheesecroissantcontains364Calories.Howmanyhours (each month)mustIwalk to workoffamonth’sworthofcroissants if I have croissants3 timesaweek? Assumethatonemonth =4weeks.(7.9)
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HonorsChemistry
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6)Onadistantplanet, thesmallestmonetaryunitis theweight.Themonetaryscaleisasfollows:
100 weights =1 crown,20crowns=1royal
Haigushidescost13 crownsperbundle.Abundlecontains25haigushides.Whatis the costof a single haigus hidein weights?(52)
7)Convert4.00g/cm3to kg/dm3(4)
8)Convert0.0598mg/cm3 to g/cm3(5.9810-5)
9)Convert6.72dm3/sto L/min(403.2)
10)Afamilypoolholds10,000gallonsof water. Howmanycubicmetersis this?(37.8)
11)A space scientist landedon Marsand stumbled uponachemical stockroom. HeaskedtheMartian attendantfor28gramsofformaldehydetorenew thefuelcellforhisradiotransmitter.TheMartian replied,"Howmanyzoomsofformaldehydeis that?" Holdon!Differentmassunitsfromthose usedon Earth. ThemassunitsonMarswerezings,zooms,andwarps.
If5 zings=4 grams,2 warps=3 zings,and 9 zooms=5 warps,howmanyzoomsdid thespace scientist request?(42)
12)Whatis thecostof6 onionsif3 onionsweigh1.5lb andthepriceofonionsis11centsperlb?
(0.33)
13)Howmanyhourswillit taketodrive toLos AngelesfromSanFranciscoifanaveragespeedof 72 mi/hrismaintained?Thedistance betweenthetwo citiesis 405miles.(5.625)
14)Whatis thecosttodrivefromSanFrancisco toLos Angeles(405mi)ifthecostof gasolineis$1.32
/gal and theautomobile gets18mi/gal? (29.70)
15)Howmanyoranges arein acrateifthepriceof acrateis$1.60 and theprice oforangesis
$0.20/lb. On the average,there arethreeorangesperpound.(24)
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16)Achemistryteacher workingatagolfcamp duringthesummerfound aliquid,whichcausedhim to slice ball afterballintothewater withoutdisturbinghim atall.He thought that thiswas animportant liquid to identify sohe setout to determineits density.Hefoundthatasampleof theliquidhad amassequal to
455 golfballs and occupiedavolumeof 620water cups thatheobtained at the7thhole.Eachgolfball massed50gand thewatercups at the7thhole of thegolfcourseheld45mL each. Whatis thedensityof the unknownliquid?(0.82)
17)A blockofice measures24in. x36in. x 18in. Whatis thevolumeof this blockin cubicmeters?(0.25)
18)Ifaprojectiletravels3.00 x 103 feetinonesecond,howfar willit travelin18minutes.(3,240,000)
19)Ifaswimmerswims85.4 yardsin fiveminutes, howmanymeterswills/heswimin 70.0 seconds?(18.22)
20)Saffroncosts$368.00 perounce.Determinehowmanygramsyou can purchasefor $15.00.(1.16)
21)Howmanygrams areequivalentto1.80x 10-4tons?(163.3)
22)Agasstationischarging$1.299 pergallonof gas.Ignoring thefact thatthisquestionwasclearlywritten many, manyyears ago,whatwould bethepriceforaliterofgas?(0.34)
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HonorsChemistry
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WS2.7StillMoreFactorLabel(Extra Practice)
1)Determinethenumberof yearsin8.35x106 minutes.(15.9)
2)Aquartof a liquid hasamassof2.70kilograms.How manyquartswillit taketoweigh100.0pounds?
(16.8)
3)Convert4.7km/hto m/s(1.3)
4)Aparticular typeoforecontains10 gramsofgold per1000kgofore.If gold isworth$400.00anounce, what massoforemust be mined toobtain gold worth$1,000,000?(7,087,500)
5)Acar consumes25.00 gallonsoffuelwhendrivingadistanceof 400.0km.Howmanygallonswillit consumewhendriving250.0miles?(25.14)
6).0054weeksisequivalent tohowmanyminutes?(54.432)
7)Howmanyfeetpersecondisawavegoingifittravelsadistance ofonemilein 7.35 seconds?(718.4)
8)Themeasuredwavelength ofa sampleof yellow lightis1.60 x 10-8ft.Express thiswavelengthinnm.(4.9)
9)Howmanyseconds arerequiredforawave travelingat600.0 milesin anhour to goadistanceof 700.0 feet? (0.795)
10)Sound travelsapproximately atarateof 1.50 x10-3meterspersecond throughwater.Determinethisratein milesperhour.(3.310-3)
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11)A student's ageis16.25 years.Determinehis/herageindays.(Use365.25days/year)(5935)
12)The approximatetotalnumberofminutesfora semesterofschool(includingeveningsand weekends)is
181,440.Howmanyweeksis this?(18)
13)Aduckhawk candiveatarateof175.0milesperhour.Howmanyminutesmustaduckhawkfly totravel
80.0miles? (27.4)
14)Howmanygrams areequivalentto125lbs?(56,700)
15)Sound travelsapproximately atarateof 344meterspersecond throughair.Determinethisratein miles perhour.(769.7)
16)Aflockof birdsconsumes40.0poundsof seed infour days.Howmanyweekswillit takefor the birds to consume1400 kgof seed?(44)
17)Ifaone-centcoinweighs3.16g,whatwouldbethedollarvalueof 1kgof one-centcoins? (3.16)
18)Ifthedensityof copperat20oCis8.933g/cm3,whatwould bethevolumeof aone-centcoppercoinat
20oC?(0.35)
19)Thedensityof a sodiumhydroxidesolutionis1.1589g/mL.Whatisthemassof 550mLof this solution?
(637.4)
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HonorsChemistry
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20)Becauseyou neverlearneddimensionalanalysis,you have beenworkingatafastfoodrestaurantfor the past 35yearswrappinghamburgers. Each houryouwrap184 hamburgers.you work8hoursperday.you work 5 daysaweek.yougetpaid every2 weekswith a salaryof $840.34.How manyhamburgerswill youhavetowrap tomakeyour firstonemillion dollars?[You arein aclosed loop.Ifyou cansolvethe problem, youwillhavelearned dimensional analysis andyoucangeta betterjob.But, since youwon'tbe working thereany longer, your solutionwillbewrong.Ifyoucan'tsolvetheproblem,you cancontinue working whichmeans theproblemis solvable,but youcan't solveit. Wehavedecidedtooverlook this impasseand allow you to solvethe problem asifyouhadcontinuedtowraphamburgers.](17,516,719)
21)The unitoflandmeasurein themetricsystemis thehectare.Inthe English system,itis theacre. Ahectare isequal toexactly100meterson a side. Ifonehectareisequal to2.47acres,howmanysquarefeetare there inoneacre?(43,319)
22)Thelegal limitfor alcoholsobrietyis0.10% alcoholbyvolume in bloodplasma.HowmanymL of alcoholin 3.0qtof blood plasmadoesthisrepresent?(2.838)
23)Sodiumhydrogencarbonate,knowncommerciallyasbaking soda,reactswith acidicmaterials such as vinegar torelease carbondioxidegas.Anexperimentcallsfor0.348kgof sodiumhydrogencarbonate. Express thismassinmilligrams.(348,000)
24)Thetotal amountoffreshwateronearthisestimatedtobe 3.73X108 km3.Whatis thisvolumeincubic meters? In liters?(3.731017;3.731020)
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HonorsChemistry
2016-2017
WS6.1 Calculate Molar MassSHOWWORK!!!!!!
1.Pb2. Ca
3. Zr4. Ne
5. aluminum6. oxygen atom
7. iodine atom8. radium atom
9. P2O3 (110)10.BaSO4 (233)
11. Mg(C2H3O2)2 (142)12.Na
13.(NH4)2SO4 (132)14.nitric acid(63)
15.Br2 (160)16.lithiumcarbonate(74)
17.disiliconhexachloride(269)18.H2O2 (34)
19.oxygenmolecule(32)20.C2H2 (26)
21.ammoniumhydroxide(35)22.C6H8O6(176)
23.PtCl2 (266)24.C19H28O2(288)
25.fluorinemolecule(38)26.manganese atom
27.P4 (124)28.methane (16)
29.octane (114)30.sugar (C6H12O6)(180)
31.sulfuric Acid (98)32.magnesium chloride(95)
33.calciumphosphide(182)34.NaBr(103)
35.Na2O(62)36.PO4- (95)
37.LiNO3 (69)38.KHCO3 (100)
39.Calciumiodite (358)40.Lead(II)Nitrate(331)
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HonorsChemistry
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WS6.2 MoleMapProblems
Calculatethemassingramsofeachofthefollowing:
1.5.0 molesofC(6.0101)2. 8.00molesof Al(216)
3. 10.5molesof O2(336)4. 200molesof Cl2 (14,200)
5. 4.00molesof Hg(802)6. 7.00 molesofI2 (1780)
7. 6.20molesofMg (151)8. 9.20molesof Fe(514)
Calculatethenumberofmolesofatomsinthefollowing:
1.800 gofCa(20)2. 280gofFe(5.0)
3. 560gofBr(7.0)4. 72gMg (3.0)
5. 66gofMn (1.2)6. 93gofP (3.0)
7. 80kg of S(2500)8. 1035gofPb(4.995)
Calculatethenumberofatomsin:
1. 3.2molesof magnesium(1.91024)2. 5.4molesofiron(3.31024)
3. 8.1molesofsodium(4.91024)4. 10.0molesoftitanium(6.021024)
Calculatethenumberofmolesofatomsinthefollowing:
1.3.011023 atomsofzinc(0.500)
2. 9.031023 atomsof S(1.50)
3. 1.8061024 atomsof Ba(2.999)
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Calculatethenumberofatomsin:
1.0.5moleof P4 molecules (1.21024)2. 24gramsofO3 molecules (9.01023)
3. 84grams of iron atoms(9.11023)4. 96grams ofS8 molecules(1.81024)Calculatethemassingramsofeachofthefollowing:
1.5.00 molesofZnO(407)2. 12.0molesof HCl(438)
3. 6.00molesof H2SO4 (588)4. 7.500molesofsugar,C12H22O11 (2567)
5. 200molesof Al2O3 (20,000)6. 40.0 molesofNa2CO3 (4240)
7. 80.0molesof methane (CH4)(1280)8. 8.2molesof CaCO3 (820)Calculatethenumberofmolesineachofthefollowing:
1.400 gramsofNaOH(10)2. 2700gramsofH2O(150)
3. 814gramsofCa(OH)2 (11.0)4. 3.0 kilogramsofCaCO3 (3.0101)Calculatethefollowing:
1.massof192molesof HCl (7.00103)
2. molesin510 gramsof Al2O3 (5.0)
3. massof17.2 molesofNa2O(1070)
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HonorsChemistry
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WS6.3 MoreMoleMapProblems
1)Calculatethe numberofmolesin
9.03X1023atomsofCu(1.5)
3.76X1025moleculesofSO2 (62.4)
8.6X1018 electrons(1.410-5)
2) Calculatethe numberofmoleculesin
12.5gofnitrogen,N2 (2.691023)
0.76gof ammonia, NH3 (2.71022)
0.60gofhydrogen,H2 (1.81023)
3) Calculatethe massof
4.25X1024atomsof C (84.7)
6.02X1021moleculesof H2O(0.180)
4) Calculatethe massof
2.00molesof water, H2O(36.0)
4.38molesof chlorine,Cl2 (311)
0.025molesofammonia,NH3(0.43)
1.8molesof oxygen, O2(58)
5) Howmanymolesarein15 gramsof lithium? (2.16)
6) Howmanygrams arein 2.4molesof sulfur?(77)
7) Howmanymolesarein9.8gramsof calcium?(0.24)
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8) Howmanygrams arein 4.5molesof sodiumfluoride,NaF?(190)
9) Howmanymolesarein 68 gramsof copper(II)hydroxide,Cu(OH)2? (0.70)
10)Howmanygrams arein 2.3x10-4molesof calciumphosphate,Ca3(PO3)2?(0.064)
11) Whatmassofcarboncontainsthe samenumberofatomsas1.008gof hydrogen?(12.01)
12)Whatmassofoxygencontainsthe samenumberofatomsas14.01gof nitrogen?(16.00)
13)Whatmassofnitrogencontainsthesame numberof atoms as48gofoxygen?(42)
14)Whichweighsmore,1 mole ofhelium atomsor 0.5 moleof carbonatoms?
15)There are50 billiongold atomsineverydropof seawater! (1drop =0.05ml) Isitfeasible to"mine" theoceanforgold?Inotherwords,howmanygallonsof seawater wouldhave tobestripped ofits goldtoproduce1 troyounceof thepreciousmetal worth$283.
(1 troy ounceis31.1g) (30,000,000)
16)Howmanymolesof sodiumnitratearein 1.70 gramsofsodiumnitrate,asubstanceused in fertilizers and to makegunpowder.(0.020)
17)Ammoniumsulfateis afertilizerused to supply both nitrogen and sulfur. Howmanygrams of ammonium sulfatearein 35.8 molesof(NH4)2SO4.(4730)
18)A0.500 molsampleof tablesugar,C12H22O11,weighshowmanygrams?(171)
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HonorsChemistry
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19)A solutionofzincchloride,ZnCl2,in wateris used tosoak theendsof woodenfence poststo preservethemfromrotting while they are stuckin theground.Oneratio usedis 840grams ZnCl2 to4Lwater. HowmanymolesofZnCl2 arein840gramsof ZnCl2? (6.2)
20)In theearly1970s,thalliumsulfate,apowerfulpoison,wasillegally usedin poison baits to controlpredatorssuch ascoyoteson westernrangelands.Hundredsofeaglesdiedafter takingthese baits.A1.00kilogramcanofTl2SO4 containshowmanymolesof this compound?(1.98)
21)Borazon,onecrystallineformofboron nitride,BN,isvery likely thehardestof all substances. Ifonesamplecontains3.02X1023atomsofboron,howmanyatomsandhowmanygramsofnitrogen are alsoin thissample?(3.021023;7.02)
22)Ifiodineisnotin aperson's diet,a thyroid condition calledgoitredevelops. Iodized saltis all thatit takes topreventthisdisfiguring condition.Calciumiodateis added totable salt to make iodizedsalt.Howmanyatomsofiodine arein0.500molesof calciumiodate? How manygramsofcalciumiodate areneeded to supply thismuchiodine?(3.011023;195)
23)Ammoniumnitrateisusedasafertilizer and tomanufacture explosives. How many atomsofnitrogenarein0.665molesof thissubstance?Howmanygramsof ammonium nitratesupply thismuchnitrogen?(8.01023;53.2)
24)Sodiumperborateispresentin"oxygenbleach".It actsbyreleasingoxygen,whichhas bleaching ability.Howmanygramsof sodiumperboratearein 4.65molesof NaBO3?
(3.80102)
25)Bariumsulfate,BaSO4,isgiven topatients asa thickslurryinflavored water beforeX-rays aretakenof theintestinal tract. Thebarium blocks theX-rays,and thetractthereforecastsa shadowthatis seenonthex-rayfilm.Howmanygrams arein0.568 mole of barium sulfate. (133)
26)Whydoes100.0 gramsof ammonia,NH3,havesomanymoremolesthan100.0 gramsof cholesterol, C27H46O?
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27)Itisestimated thatasampleofmatter contains1.38X1025atoms. Howmanymolesare present in thesample?(22.9)
28)Howmanymolesof barium arepresentin asamplehavingamassof22.3 grams?(0.162)
29)Achemicalreactionrequires3.7molesof boron. Whatmass,in grams,of boronmustbe usedin thereaction?(4.0101)
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HonorsChemistry
2016-2017
WS6.4 CalculatingwithPercent Composition
1.Calculatethepercentageof ironiniron(II)oxide.(77.7)
2. Calculatethepercentof oxygeninmercury(II)oxide.(7.39)
3. Calculatethepercentageof waterinCalciumSulfatedihydrate.(20.9)
4. Findthepercentageof eachelementinNH3(82.2N;17.8H)
5. Calculatethe massin kg of titaniumin1.0kgof titanium(IV) oxide.(0.599)
6. Calculatethe massof aluminumin2500gramsof aluminumoxide.(1320)
7. Whatis the massin gramsofmanganesein 50kgof anore thatis60.0%manganese (IV) oxide?(18953)
8. Calculatethepercentageof tinin tin(IV)oxide(78.8)
9. Calculatethepercentageof oxygenin sulfur trioxide.(59.9)
10.Calculatethe massof lead in 1500gramsLead (II)oxide.(1400)
11.Whatis the massofmercuryfoundin 3.5kgofanore thatis 35.0%mercury(II)sulfide?(1056)
12.Animportantoreofchromiumcontains5.00%chromite(FeCr2O4).Whatmassof chromiumwill be found in10.0 kgof thisore?(232)
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13. Calculatethepercentageof copperin each of thefollowingminerals: Cuprite,Cu2O(88.8)
Copper pyrites,CuFeS2 (34.6)
Malachite,CuCO3·Cu(OH)2 (57.5)
14. Using answer fromquestion13,Howmanytonsof cupritewillgive 500tonsof copper.(600)
15. Whatis thenitrogencontentof: NH4NO3 (35)
(NH4)2SO4 (21)
16. Determinethe percentagecompositionof: Silverchromate, Ag2CrO4 (65,16,19)
Calciumpyrophosphate, Ca2P2O7 (32,24,44)
17. Determinethe percentagecompositionof: UO2F2 (77,10,12)
C3Cl2F6 (16,32,52)
18. Findthepercentage arsenic inapolymerhavingtheempiricalformulaC2H8AsB.(63.6)
19. Whatweightof silveris presentin 3.45gAg2S?(3.00)
20. Determinethe weightof sulfur required tomake100lbH2SO4.(30lb)
21. Howmanypoundsofmetallic sodiumand liquid chlorinecanbeobtained fromonetonof salt?(786;1213)
22.A12.00gramsampleof acrudeorecontains2.89%HgS.Whatis thepercentageofmercuryin the ore? (2.49)
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HonorsChemistry
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WS6.5 Empiricalformulas
1.Derivetheempiricalformulasof thesubstanceshavingthefollowingpercentage composition:
a.Fe=63.53%,S =36.47%(FeS) b. Fe=46.55%,S=53.45%(FeS2) c.Fe=53.73%,S=46.27%(Fe2S3)
2. Acompoundcontains21.6% sodium,33.3%chlorine,45.1%oxygen.Deriveits empirical
formula. (NaClO3)
3. When1.010gramsof zinc vapor isburnedin air,1.257 gramsof an oxide of zincisproduced.
Whatis theempiricalformulaof theoxide? (ZnO)
4. Determinethesimplestformulaof acompound thathas thefollowingcompositions:Cr =
26.52%,S=24.52%,O =48.96% (Cr2S3O12)
5. A3.245 gsampleof a titaniumchloride wasreducedwith sodiumto metallic titanium.
Aftertheresultant sodiumchloride waswashedout, theresidualtitanium metalwasdried andweighed0.819g.Whatis theempiricalformulaof titaniumchloride?(TiCl4)
6. Acompoundcontains63.1 carbon,11.92%hydrogen,and 24.97%fluorine.Deriveits empiricalformula.(C4H9F)
7. Anorganiccompoundwas foundon analysis toconsistof47.37%carbonand 10.59% hydrogen.Thebalance waspresumedtobeoxygen.Whatis theempiricalformulaof the compound?(C3H8O2)
8. A borane(acompoundcontainonly boronand hydrogen)analyzed 88.45% boron.What isits empiricalformula?(B2H3)
9. Anexperimentalcatalystusedin the polymerizationofbutadienehas thefollowing composition: 23.3%Co,25.3%Mo,and51.4%Cl.Whatis itsempiricalformula? (Co3Mo2Cl11)
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WS6.6 Molecular Formulas
Determinetheempiricalformulaforeach of thefollowing substances. The percentage composition isgiven.Thenfind the molecularformulabyusingthe molar mass.
1.92.3%carbon;7.7%hydrogenMolar mass–78 g/mol(C6H6)
2.5.88%hydrogen,94.12%oxygenMolar mass --34g/mol(H2O2)
3.30.43%nitrogen;69.57%oxygenMolar mass–138 g/mol (N3O6)
4.12.5%hydrogen;37.5%carbon;50.0%oxygenMolar mass–64g/mol(H8C2O2)
5.47.4% sulfur;52.6%chlorineMolar mass–135 g/mol(S2Cl2)
6.30.43%nitrogen;69.57%oxygenMolar mass–92g/mol(N2O4)
7.73.8%carbon;8.7%hydrogen;17.5%nitrogenMolar mass–166 g/mol (C10H14N2)
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HonorsChemistry
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WS6.7 Review Problems
1.Aluminumsulfateis acompound used in sewagetreatmentplants.
a.HowmanyatomsofSarein onemoleof aluminumsulfate?(1.81 x 1024)
b. HowmanymolesofSarein 1molealuminumsulfate? (3)
c.HowmanyatomsofAl areinonemoleof aluminumsulfate?(1.20 x 1024)
2. Butane(formulaC4H10)is thevolatileliquidfuelin disposablecigarettelighters. a.Whatis the mole ratioof CtoHin thiscompound?
b. HowmanymolesofCarein 3.00molof butane?(12)
c.Whatis the molarmass forbutane?(58)
d. IfIhave2.5molesof butane,howmanygramsof butanedoIhave?(145)
3. Give themass(ingrams)foreach of thefollowing:
a.2.5molesmagnesium(60.8)
b. 0.13molescarbon(1.56)
c.7.24molesstrontiumoxide (7.50102)
d. 3.21016atoms sulfur(1.7110-6)
e.7.531027molecules sodiumchloride(731,736)
4. Calculatetheformulamass foreach of thefollowingandroundtothenearest0.1 amu. a.Magnesium oxide(40.0)
b. Calciumchloride(110.9)
c.Phosphoruspentachloride(209.2)
d. S2Cl2 (135.2)
e.Na3PO4 (163.9)
f.Magnesium sulfateheptahydrate(246.4)
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5. Whatis the massingramsof2.33molof penicillin,C16H18O4N2S?(778)
6. Howmanymolesof sodium bicarbonate,NaHCO3 (baking soda),arein a242-gram sample?(2.88)
7. Howmanymolesof potassiumatoms arein 125 gramsofKCl?(1.68)
8. Whatis the mass,in grams,ofoneatomof Fe?(9.310-23)
9. Howmanymoleculesof sucrose(C12H22O11)arein 25.00gramsof sucrose?(4.4031022)
10.Howmanyatomsofcarbon aretherein 3.2molesofcarbon?(1.91024)
11. Calculatethepercentcomposition for thefollowing:
a.FeCl3(34;65)
b. SodiumSulfate(32;23;45)
c.(NH4)2HPO4 (21;7;23;48)
12.Calculatethe massinhydrogenin12.0gramsofNH3. (2.12)
13.Arsenic reactswith oxygentoformacompound thatis75.7% arsenicand 24.3%oxygen, by mass.Whatis theempiricalformulaof thiscompound?(As2O3)
14.A1.31grams sampleof sulfurwasallowed toreactwithanexcessof chlorineto produce
4.22gramsof aproduct thatcontainsonlysulfur and chlorine.Whatis theempirical formula of thecompound?(SCl2)
15.A substance wasfoundtohavethefollowing compositionbymass: 60.8%sodium,28.5%
boron, and 10.5%hydrogen.Whatis theempiricalformulaof thecompound?(NaBH4)
16.Thefollowing areempiricalformulasandformulamassesforfivecompounds.Whatare theirmolecularformulas?
a.NaS2O3Molar mass=270.4 g/mol(Na2S4O6)
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b. C3H2ClMolar mass=147.0 g/mol(C6H4Cl2)
c.Na2SiO3 Molar mass=732.6 g/mol(Na12Si6O18)
17.Determinetheempirical andmolecularformulasforeachof thefollowing:
a.Ethylene glycol,the substanceused as theprimarycomponentofmostantifreeze solutions: 38.7%C,9.7%H,and 51.6%O bymass;Molar mass=62.1 g/mol (C2H6O2)
b. Caffeine,a stimulantfoundincoffee:49.5%C,5.15%H,28.9%N and16.5%O
bymass; Molar mass=195g/mol(C8H10N4O2)
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WS6.8MoreMoleReview
1.Howmanymolesaretherein45.0gof acetic acid,HC2H3O2?(0.75)
2. Whatis the massinkgof 125.50molesofStrontium nitrate,Sr(NO3)2? (26.56)
3. Whatis the massingramsof3.50x1021moleculesof Uraniumhexafluoride, UF6? (2.05)
4. 7.46x1024atomsofgoldhave whatmass?(2441)
5. Howmanymolesaretherein1.0lb.of tablesugar?(Tablesugar is sucrose,C12H22O11;1lb.=
453.6 grams)(1.3)
6. Water hasadensityof 0.997gpermilliliter.Whatis themassof250.0ml(acupful)of water?
Howmanymolesof water doesthisrepresent?(13.9)
7. DeterminethepercentcompositionofKClO3. (31.9;29.0;39.1)
8. Whatis thepercentageofwaterin strontiumchloridehexahydrate?(41)
9. Whatmassof seleniumisfoundin 683gramsofsodium selenite,Na2SeO3?(312)
10.A sampleof silversulfide,Ag2S,hasamassof 62.4 grams.Whatmassofeachelementcould be obtainedbydecomposingthis sample?(54.3;8.11)
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11. Determinetheempiricalformulaforacompound thatis93.5%niobiumand 6.50%oxygen. (Nb5O2)
12.A sampleof thecompoundcopperfluoridehasamass of0.858 grams.The sample contains
0.321gramsoffluorine. Whatis theempiricalformulaforthiscompound?(CuF2)
13.Acompoundhas anempiricalformulaofC2H2O.Itsmolarmassis254g/mol.Usethe experimentalmolarmasstodetermine themolecularformulafor thecompound.(C12H12O6)
14.A2.65-gram sampleof powdercontains0.70gramsofchromium,0.65gramsof sulfur. The otherelementin thepowderisoxygen.The compound hasamolarmassof392.2g/mol. Determine themolecularformulafor thecompound.(Cr2S3O12)
15.Histamineis a substance released bycellsinresponsetoinfection,stingsor allergies. A sampleof histamine iscomposedof 208mgof carbon,31mgofhydrogen, and 146mgof nitrogen.Its molar massis111g/mol. Whatis the molecularformulaforhistamine?(C5H9N3)
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