CHEM%1310% Sample%Final%Exam% % 5.%What%is%the%formula%of%the%organic%molecule%below?% % %

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1 CHEM1310 SampleFinalExam 1.Antimony,Sb,hastwostableisotopes.Giventhat43.8ofnaturalantimonyis 123Sbwiththeexperimentallydeterminedmass amu,whatistheother stableisotope? A) 120 Sb B) 121 Sb C) 122 Sb D) 123 Sb E) 124 Sb 2.Whatisthechemicalformulaforthecompoundcontainingtheiron(III)cation andthesulfateanion? A)Fe3SO4 B)FeS C)Fe3(SO4)2 D)Fe2(SO4)3 E)Fe2S3 3.Agivenisotopecontains92protons,146neutrons,and86electrons.Whatisthe chemicalsymbolforthisisotope? A) U 6+ B) U C) Rn D) Rn 6+ E) 146 U 6+ 4.Alaboratoryanalysisofanunknownsoliddeterminedthefollowingmass percentcomposition: Ca=54.09 H=2.72 O=43.19 Whatistheempiricalformulaforthesolid? A)Ca(OH)2 B)Ca27O22H C)CaOH D)Ca0.337O0.675H0.668 E)Ca4(OH)8

2 CHEM1310 SampleFinalExam 5.Whatistheformulaoftheorganicmoleculebelow? A)C3H6O3 B)C3H2O3 C)CH2O D)C3H3O6 E)CHO2 6.WhatisthesolidproducedwhenK3PO4reactswithCa(NO3)2? A)KNO3 B)Ca3(PO4)2 C)Ca 2+ D)NO3 \ E)K 7.Howmanymolesofcarbonaretherein650.5gramsofglucose,C6H12O6? A)2.17x10 24 B)3.61 C)0.277 D)21.7 E)1.30x Fiveliters(5.00\L)ofanaqueoussolutionispreparedbycompletedissolutionof 40.00gofFeCl2.Whatisthechlorideion(Cl \ )concentrationofthissolution?the molarmassoffecl2is126.75g/mol. A)0.0631M" B)0.0315M" C)0.0876M" E)0.0438M" E)0.126M"

3 CHEM1310 SampleFinalExam 9.HowmuchC2H2canbeproducedwhen100.gofH2Oreactswith100.gofCaC2 accordingtothereactionbelow? CaC2(s)+2H2O(l) Ca(OH)2(aq)+C2H2(g) A)72.25g B)40.62g C)144.5g D)31.63g E)112.9g 10.Ifthepercentyieldofthereactionis74.2when24.0gofNaHCO3isheated, thenhowmuchna2co3isformed? Molarmasses:NaHCO3=84.01g/mol;Na2CO3=105.99g/mol;CO2=44.01g/mol; H2O=18.01g/mol A)15.1g B)11.2g C)22.3g D)26.4g E)30.3g 11.WhatisthepartialpressureofCOinacontainerthatholds5.0molesCO(g),3.0 molesofn2(g),and1.0moleofh2(g)andhasatotalpressureof1.05atm? A)0.42atm B)0.53atm C)0.58atm D)0.47atm E)Thereisnotenoughinformationtoanswerthisquestion. 12.Anidealgasdiffersfromarealgasinthatthemoleculesofanidealgas. A)haveanaveragemolecularmass. B)havenokineticenergy. C)haveamolecularweightofzero. D)havenoattractionforoneanother. E)takeupasignificantamountofvolumeincomparisontothevolumeofthe sample.

4 CHEM1310 SampleFinalExam 13.ThegraphbelowrepresentsthegasesHe,Ar,N2,andCH4allatthesame temperature.whichstatementregardingthisgraphistrue? A)Curve3representsN2. B)Curve1representsN2 C)Curve4representsAr. D)Curve2representsHe. E)Curve3representsCH4. 14.Anewlydiscoveredsubstanceinthegasphasehasdensityof2.39g/Lat25.0 o C and0.941atm.whatisthemolarmassofthesubstance? A)16.1g/mol B)62.1g/mol C)5.21g/mol D)0.0919g/mol E)Thisproblemcannotbesolvedwithoutthevolumeofsample. 15.WhatmassofP4(s)isrequiredtocompletelyconsume25.0LofH2(g)at27.0 o C and0.976atminthepresenceofexcessoxygen?themolarmassofp4is g/mol.ThemolarmassofH2is2.02g/mol. P4(s)+6H2(g)+8O2(g) 4H3PO4(s) A)0.202g B)20.5g C)1.21g D)123g E)246g

5 CHEM1310 SampleFinalExam 16.Howmanyunpairedelectronsareinagroundstatevanadium(V)atom? A)0 B)1 C)3 D)4 E)5 17.Whichofthefollowinghasthelargestatomicorionicradius? A)S 2\ B)Cl C)Cl \ D)K + E)S 18.Whichsetofquantumnumberscouldcorrespondtoa4d\orbital? A) B) C) D) n=4,l=4,ml=+3 n=4,l=2,ml=+4 n=4,l=3,ml= 3 n=4,l=2,ml=+1 19.Forahydrogenatom,whichtransitioncorrelatestothelongestwavelengthof lightabsorbed? A)n=1ton=2 B)n=3ton=4 C)n=1ton=3 D)n=2ton=5 E)n=2ton=3 20.A0.500Joulelaserpulsewith780.0nmwavelengthcontainshowmany photons? A)1.96x10 18 photons B)2.55x10 \19 photons C)9.67x10 38 photons D)1.96x10 27 photons E)1.27x10 \19 photons

6 CHEM1310 SampleFinalExam 21.How many lone pairs of electrons are found on the central atom in the Lewis structure of the compound ICl 3? A) 2 B) 3 C) 4 D) 8 E) Thehybridorbitalsusedincarbons2and4,respectively,inthemoleculebelow are: A) sp 3 andsp B) sp 2 andsp C) sp 3 andsp 3 D) sp 2 ands 2 E) spd " andsp 23.Whichbondisthemostpolar? A)C H B)C C C)C S D)C O E)C N 24.Whatistheelectrongrouparrangement(electrongeometry)ofAsF3? A)tetrahedral B)trigonalplanar C)trigonalpyramidal D)bent(V\shapedorangular) E)trigonalbipyramidal

7 CHEM1310 SampleFinalExam 25.Whichmoleculecanformintermolecularhydrogenbonds(withothermolecules ofitself)? A)NH2CH2COOH B)SiH4 C)CH3COCH3 D)CH2F2 E)CH3Cl 26.Whatisap\typesemi\conductor? A) Onewithexcesselectronsinthevalenceband(valenceelectronrich). B) Onewithexcesselectronsintheconductionband(conductionelectronrich). C) Onewithaless\than\fullvalenceband(valenceelectrondeficient). D) Onewithaless\than\fullconductionband(conductionelectrondeficient). E) Onewithelectronspositivelyintheconductionband(conductionpositiveelectrons). 27.Whichstatementregardingtheimageistrue? A)Itisabodycenteredcubicunitcell,andthereare9atomspercell. B)Itisafacecenteredcubicunitcell,andthereare2atomspercell. C)Itisasimplecubicunitcell,andthereisoneatompercell. D)Itisabodycenteredcubicunitcell,andthereare2atomspercell. E)Itisafacecenteredcubicunitcell,andtherearetwoatomspercell. 28.Ranktheboilingpointsfromhighesttolowestfor: CH3OH,CH3CH3,CH2O A)CH3OH>CH3CH3>CH2O B)CH2O>CH3OH>CH3CH3 C)CH3CH3>CH3OH>CH2O D)CH3OH>CH2O>CH3CH3 E)CH2O>CH3CH3>CH3OH

8 CHEM1310 SampleFinalExam 29.When some TNT detonates, the volume of gas increases from 10.0 L to 90.0 L at a constant pressure of 1.00 atm. Additionally, 90 kj of energy is released as heat. What is ΔE for this process? ( 1 L atm = J) A)\98.1kJ B) 81.9kJ C) 8.1kJ D)+81.9kJ E)+98.1 kj 30.Youholdagramofaluminuminonehandandagramofcopperintheother; eachstartedatthesametemperature.to/fromwhichmetalwillmoreheathave beentransferredwhenbothhavereachedbodytemperature?givencs,cu=0.387 J/g C,dCu=8.93g/cm 3,Cs,Al=0.900J/g C,anddAl=2.70g/cm 3. A)Copper,becauseit sspecificheatcapacityislower B)Copper,becauseit sdensityishigher C)Aluminum,becauseit sspecificheatcapacityishigher D)Aluminum,becauseit sdensityislower E)Copperandaluminumwillreachbodytemperatureatthesametime 31.Whichstatementistrue? A)Inanendothermicreaction,theenergyoftheproductsislessthanthatof thereactants. B)Thereisnotemperaturechangeassociatedwiththeconversionoficeto liquidwater. C)Freezingisanendothermicprocess. D)Thechangeinenthalpyisequaltoqatconstantvolume. E)Noneofthesestatementsistrue. 32.Whichstatementbestexplainswhywaterfreezesonlyatorbelow0 o Cat atmosphericpressure. A)Freezingisanendothermicprocesswithanincreaseinentropy. B)Freezingisanexothermicprocesswithdecreaseinentropy. C)ThesignofΔGfortheprocessisalwayspositive. D)Freezingisanendothermicprocesswithadecreaseinentropy. E)Freezingisanexothermicprocesswithanincreaseinentropy.

9 CHEM1310 SampleFinalExam 33.Given: 1. NH3(g)+HBr(g) NH4Br(s) H rxn=\188.32kj 2. N2(g)+3H2(g) 2NH3(g) H rxn=\92.22kj 3. N2(g)+4H2(g)+Br2(l) 2NH4Br(s) H rxn=\541.66kj Whichstepsarenecessarytocalculatethe Hrxnforthisreaction: H2(g)+Br2(l) 2HBr(g) I. Reversereaction1. II. Halvereaction3. III. Doublereaction1. IV. Reversereaction2. A. I&IVonly B. II&IIIonly C. I&IIIonly D. I,III,&IVonly E. Allofthesestepsarenecessary. 34. For which reaction or process is the change in entropy greater than zero? A) NH3(g)+HBr(g) NH4Br(s) Β) N2(g)+3H2(g) 2NH3(g) C) N2(g)+4H2(g)+Br2(l) 2NH4Br(s) D)H2O(s) H2O(g) E)Na + (aq)+cl \ (aq) NaCl(s)!! 35.Whichofthestatementsbelowisnotadirectconsequenceofalawof thermodynamics? A)Entropyoftheuniverse(systemplussurroundings)increases. B)Spontaneousreactionsarefast. C)Totalenergyisconserved. D)Theentropyofacrystallinesolidapproacheszeroat0Kelvin. E)Alloftheseareconsequencesofthelawsofthermodynamics.

10 CHEM1310 SampleFinalExam 36.CalculatethenormalboilingpointofCH3CH2OH,giventhefollowing information: H vap 43.5kJ/mol H fus 4.60kJ/mol H f \278kJ/mol S vap 124J/mol K S fus 31.0J/mol K Molecularweight 46.1g/mol A) 159K B) 2240K C) 1.40e3K D) 351K E) 0.351K 37.CalculateΔG o at45.0 o CforareactionforwhichΔH o =\293kJand ΔS o =\69.5J/K. A)\271000kJ B)\290kJ C)21800kJ D)\271kJ E)2830kJ 38.The rate law for a reaction is: Rate = k[a] 2 [B]. What happens to the rate if both concentrations are doubled? A) No change B) Rate increases by a factor of 4 C) Rate increases by a factor of 2 D) Rate increases by a factor of 8. E) Not enough information 39.The rate law for a particular reaction is Rate = k[a][b]. If the initial concentration of B is increased from 0.1 M to 0.3 M (while the concentration of A is held constant), the initial rate will increase by which of the following factors? A) 2 B) 27 C) 4 D) 6 E) 3

11 CHEM1310 SampleFinalExam 40. A eneral reaction written as 2A + 2B C + 2D is studied and yields the following data. [A] 0 [B] 0 Initial Δ[C]/Δt M M mol/l s M M mol/l s M M mol/l s What are the proper units for the rate constant for the reaction? A) 1/s B) M/s C) 1/M s D) 1/M 3 s E) 1/M 2 s 41.The rate constant, k, for a chemical reaction is dependent on A) the concentration of the reactant. B) the concentration of the product. C) the temperature. D) enthalpy. E) none of these 42.A1.00atmsampleofH2Sisallowedtodecomposeat1405Kuntilequilibriumis achieved.atequilibrium,thepartialpressureofs2is0.0370atm.whatisthevalueofkfor thisreaction? A)2.36x10 \4 B)2.96x10 \3 C)1.42x10 \3 D)4.24x10 3 E)7.04x10 2 2H2S(g) S2(g)+2H2(g)

12 CHEM1310 SampleFinalExam 43.Selecttheequilibriumexpressionforthereaction: P4(s)+3KOH(aq)+3H2O(l) PH3(aq)+3KH2PO2(aq) ANS:E 1 A) K = [P 4 ][H 2 O] 3 B) K = [KOH] 3 [PH 3 ][KH 2 PO 2 ] 3 C) K = [PH ][KH PO ]3 [P 4 ][KOH] 3 [H 2 O] 3 D) K = [PH 3 ][KH 2 PO 2 ]3 [KOH] 3 [H 2 O] 3 E) K = [PH ][KH PO ]3 [KOH] An increase in total pressure (at constant temperature) for the following reaction causes: A(g) + B(g) C(g) + heat A) increase in the number of moles of A B) decrease in the number of moles of A C) no change in the number of moles of A D) an undetermined effect on the number of moles of A 45. Calculate the [H + ] in a M solution of HCN, K a = A) M B) M C) M D) M E) none of these!!

13 CHEM1310 SampleFinalExam 46. ThevalueofKforthereactionN2O4(g) 2NO2(g)atagiventemperatureis IftheequilibriumpartialpressureofNO2atthesametemperatureis0.0172bar, thenwhatistheequilibriumconcentrationofn2o4? A) B) C) D) E) Thegalvaniccellshownbelowusesthehalf\cellsMg 2+ /MgandZn 2+ /Zn,anda saltbridgecontainingkcl(aq).thevoltmetergivesapositivevoltagereading. Whichstatementcorrectlyidentifiestheanodeandcathodecompartmentsandthe reactionsthatoccurinthem? Mg 2+ (aq)+2e \ Mg(s) E o =\2.37 Zn 2+ (aq)+2e \ Zn(s) E o =\0.76V A)AandErepresentthecathode:Zn 2+ (aq)+2e \ Zn(s) B)BandFrepresentthecathode:Mg 2+ (aq)+2e \ Mg(s) C)AandErepresenttheanode:Mg 2+ (aq)+2e \ Mg(s) D)BandFrepresenttheanode:Zn(s) Zn 2+ (aq)+2e \ E)BandFrepresentthecathode:Zn 2+ (aq)+2e \ Zn(s) 48.WhatistheoxidationstateofNinSn(NO3)4? A)\3 B)+2 C)+3 D)+4 E)+5

14 CHEM1310 SampleFinalExam 49.Whichreactioncorrespondstothecelldiagram? Pt(s) H2(g) H+(aq) Ag+(aq) Ag(s) A)H2(g)+2Ag + (aq) 2H + (aq)+2ag(s) B)2H + (aq)+pt(s)+2ag(s) H2(g)+2Ag + (aq) C)2H + (aq)+ag(s) H2(g)+Ag + (aq) D)Pt(s)+H2(g)+2Ag + (aq) 2H + (aq)+2ag(s) E)H2(g)+Ag + (aq) 2H + (aq)+ag(s) 50.Whatisthestandardcellpotential(E o cell)whenagalvaniccellisconstructed usingthefollowinghalf\reactions? Au 3+ +3e \ Au(s) E o =+1.50V Cu + +e \ Cu(s) E o =+0.52V A)+0.52V B)+0.98V C)+2.02V D)\0.98V E)\2.02V