9.0122
11
12
Na
Mg
22.990310Committee
IA
1
H
1.008
IIA
3
4
Li
Be
6.941 THEUNIVERSITYOFMANITOBA
March42010
MIDTERMEXAMINATION
PAPERNOXXX
PAGENO:1of2DataPages
DEPARTMENT&COURSENO:CHEM1310
TIME:2HOURS
EXAMINATION:UniversityIChemistry:Intro.toPhys.Chem.
EXAMINER:CHEM1 24.305
VIIIA
2
He
IIIA
IVA
VA
VIA VIIA 4.003
5
6
7
8
9
10
B
C
N
O
F
Ne
10.81 12.011 14.007 15.999 18.998 20.179
atomic number
Symbol
atomic mass
IIIB
IVB
VB
VIB
VIIB
VIIIB
IB
IIB
19
20
21
22
23
24
25
26
27
28
29
30
K
Ca
Sc
Ti
V
Cr
Mn
Fe
Co
Ni
Cu
Zn
39.098 40.08 44.956 47.88 50.942 51.996 54.938 55.847 58.933 58.69 63.546 65.38
37
38
39
40
41
42
Rb
Sr
Y
Zr
Nb
Mo
85.468 87.62 88.906 91.22 92.906 95.94
43
Tc
(98)
13
14
15
16
17
18
Al
Si
P
S
Cl
Ar
26.982 28.086 30.974 32.06 35.453 39.948
31
Ga
69.72
32
33
34
35
36
Ge
As
Se
Br
Kr
72.59 74.922 78.96 79.904 83.80
44
45
46
47
48
49
50
51
52
53
54
Ru
Rh
Pd
Ag
Cd
In
Sn
Sb
Te
I
Xe
101.07 102.91 106.42 107.87 112.41 114.82 118.69 121.75 127.60 126.90 131.29
55
56
57
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
Cs
Ba
La
Hf
Ta
W
Re
Os
Ir
Pt
Au
Hg
Tl
Pb
Bi
Po
At
Rn
132.91 137.33 138.91 178.49 180.95 183.85 186.21 190.2 192.22 195.08 196.97 200.59 204.38 207.2 208.98 (209) (210) (222)
87
88
89
Fr
Ra
Ac
(223) 226.03 227.03
58
59
60
61
62
63
64
65
66
67
68
69
70
71
Ce
Pr
Nd
Pm
Sm
Eu
Gd
Tb
Dy
Ho
Er
Tm
Yb
Lu
140.12 140.91 144.24 (145) 150.36 151.96 157.25 158.93 162.50 164.93 167.26 168.93 173.04 174.97
90
91
92
93
94
95
96
97
98
99
100
101
102
103
Th
Pa
U
Np
Pu
Am
Cm
Bk
Cf
Es
Fm
Md
No
Lr
232.04 231.04 238.03 237.05 (244) (243) (247) (247) (251) (252) (257) (258) (259) (260)
You may tear off this page. Please note there are useful equations given on the back of this page
For rough work use the two blank pages found at the back of Part A of the exam.
PHYSICAL CONSTANTS
CONVERSION FACTORS
Avogadros number
N = 6.022 1023 mol1
101.3 kPa = 1.00 atm
Charge on proton
e = 1.602 1019 C
1.00 atm = 760 torr or 760 mmHg
Gas constant
R = 0.0821 L atm K1 mol1
ln(x) = 2.303 log(x)
R = 8.314 J K1 mol1
1 V = 1 J C1
Plancks constant
h = 6.626 1034 J s
1 kPa L = 1 J
Speed of light
c = 2.998 108 m s1
1 J = 1 kg m2 s2
Mass of electron
me = 9.11 1028 g
1 cal = 4.184 J
Mass of proton
mp = 1.673 1024 g
1 L = 1000 cm3
Mass of neutron
mn = 1.675 1024 g
1 bar = 100.0 kPa
0.00 C = 273.15 K
OTHER USEFUL DATA:
Density of water = 1.00 g cm-3,
Specific heat of water = 4.184 J K1 g1
Kw(25 C) = 1.0 x 10-14,
Hfusion of water = 6.01 kJ/mol
Hvap of water = 40.7 kJ/mol
Paper:
576
CHEM 1310 University I Chemistry: Intro. to Phys. Chem.
SOME USEFUL EQUATIONS
For ax 2 + bx + c = 0 solutions are x =
Page: 2 of 2 Data Pages
b
b 2 4ac
2a
2a
PV=nRT
PX V = nX RT
E = q + w
G = H T S
Go = R T ln(Ko)
G = Go + RT ln(Q)
q
S = rev
T
q = Cs m T
w = Pext V
H=E+PV
At constant pressure, E = H + w
Kp = Kc (RT)ngas
ln( K 2 ) = ln( K1 )
P H vap 1
1
ln 2 =
T T
R
P
2
1
1
H 1
1
T T
R2
1
Integrated zero order rate law: [R]t = [R]o kt
[R ]
t
Integrated first order rate law: ln
[R ] = kt
0
Integrated 2nd order rate law:
1
1
=
+ kt
[ R ]t [ R ] 0
zero order half-life: t1 / 2 =
first order half-life: t1 / 2 =
[R]0
2k
ln 2
k
second order half-life: t1 / 2 =
1
k [R ]0
k = A eEa/RT
k Ea 1
1
ln 2 =
T T
R2
k1
1
ln( k ) = ln( A)
Beer's law: Absorbance = bc
pH = log[H3O+]
pOH = log[OH-]
Kw= KaK b
pKw = pH + pOH
[conjugate base]
[acid]
Henderson-Hasselbalch equation: pH = p Ka + log
Ea
RT
THE UNIVERSITY OF MANITOBA
March 4
20
10
PAPER NO:
MIDTERM
PAGE NO:
DEPARTMENT & COURSE NO:
CHEM 1310
TIME:
EXAMINATION: University I Chemistry: Intro. to Phys. Chem.
EXAMINATION
1 of 7
2
HOURS
EXAMINER: CHEM 1310 Committee
THIS EXAM CONSISTS OF TWO PARTS: Part A (multiple-choice) and Part B (free-response)
Part A of this CHEM 1310 March midterm examination paper is an objective-type, machine-scored
examination. All questions in this paper are of equal value.
Part A is worth 15 marks (or 60% of the 25 marks allotted to this midterm examination) and should
require approximately 60 minutes to complete.
There are thirty (30) questions on Part A of this examination paper.
GENERAL INSTRUCTIONS
Do not fold, staple, tear, or otherwise mutilate the answer sheet.
Indicate your answers with a bold mark on the answer sheet, using a soft lead (graphite) pencil.
If you do any erasing, be sure that erasures are complete.
Each question has ONE correct answer only. DO NOT MARK MORE THAN ONE ANSWER
PER QUESTION.
Marks will NOT be deducted for wrong answers.
Blank sheets are attached to this examination to be used for rough work.
Numerical answers are correct to within +2 in the last dsignificant digit
VERY IMPORTANT
For accurate processing of the answer sheet for this examination, we must have on your answer sheet:
1. your correct student number, and
2. your name
Write your student number in the column marked by a colored arrow on the answer sheet and score your
student number correctly in the area to the right of this column.
NO CELLPHONES, PAGERS, CALCULATORS WITH TEXT, ETC. ARE PERMITTED.
STUDENTS FOUND WITH ANY OF THESE PROHIBITED ITEMS WILL HAVE THEIR
ANSWER PAPERS CONFISCATED AND WILL RECEIVE A GRADE OF ZERO ON THE
EXAMINATION.
Submit the ANSWER SHEET for grading.
You may keep this question paper. We suggest that you record your answers so that you may compare
them against the answer key which will be available on the ANGEL course site immediately after the
examination.
Paper:
CHEM 1310 University I Chemistry: Intro. to Phys. Chem.
Page: 2 of
7
1) Whichoneofthefollowingstatementsistrue?
A) Theenthalpychangeforareactionisindependentofthestateofthereactantsandproducts.
B) Histhevalueofqmeasuredunderconditionsofconstantvolume.
C) TheenthalpychangeofareactionisthereciprocaloftheHofthereversereaction.
D) Enthalpyisanintensiveproperty.
E) Enthalpyisastatefunction.
2) Calculatetheinternalenergychange(E)forasystemthatisgivingoff45.0kJofheatandisperforming855J
ofworkonthesurroundings.
A) 44.1kJ
B) -45.9kJ
C) -44.1kJ
D) -9.00x102kJ
E) 9.00x102 kJ
3) A__________Hcorrespondstoan__________process.
A) zero,endothermic
B) positive,endothermic
C) negative,endothermic
D) zero,exothermic
E) positive,exothermic
4) Asampleofironabsorbs67.5Jofheat,uponwhichthetemperatureofthesampleincreasesfrom21.5Cto
28.5C.Ifthespecificheatofironis0.450J/g - K,whatisthemass(ingrams)ofthesample?
A) 21
B) 1100
C) 1.1x10 3
D) 11
E) 4.3
5) Onepossiblewaytoconvertseawaterintodrinkingwateristhroughdistillation.Howmuchenergyis
requiredtotake325mlofwaterat20Candconvertittosteamat100C?
A) 469kJ
B) 441kJ
C) 733kJ
D) 843kJ
E) 122kJ
6) Usethestandardreactionenthalpiesgivenbelowtodetermine Hrxn forthefollowingreaction:
P4 (g)+10Cl 2 (g)4PCl5 (s)
Hrxn=?
PCl5 (s)PCl3 (g)+Cl2 (g)
Hrxn=+157kJ
P4 (g)+6Cl2 (g)4PCl3 (g)
Hrxn =- 1207kJ
Given:
A) -1050.kJ
B) -1786kJ
C) -1835kJ
D) -1364kJ
E) -2100.kJ
Paper:
CHEM 1310 University I Chemistry: Intro. to Phys. Chem.
Page: 3 of
7
7) GiventhebondenthalpiesNH(389),ClCl(243),NCl(201),andH Cl(431)inkJ/mol,computeH in
kJ/molforNH3 (g)+ Cl2 (g)NH2 Cl+ HCl(g)
A) +71
B) -393
D) +393
C) 0
E) -1100
8) CalculatethelatticeenergyforNaCl( s)usingaBorn - Habercycleandthefollowinginformation:
Na (g + ) + Cl- (g ) NaCl(s)
?
Na(s) + 1/2Cl2 (g ) NaCl(s)
- 411.0kJ/mol
Na(s) Na(g )
Na(g ) Na + (g ) + e -
+ 107.3kJ/mol
+ 495.8kJ/mol
1/2Cl 2 (g ) Cl(g )
+ 121.7kJ/mol
Cl(g ) + e - Cl- (g )
- 348.6kJ/mol
A) -690.3kJ/mol
B) -787.2kJ/mol
C) -1512kJ/mol
D) -289.3 kJ/mol
E) -34.8kJ/mol
9) ThestandardenthalpyofformationforCuSO 4 5H2O(s)is- 2278.0kJ/moleat25C. Thechemicalequationto
whichthisvalueappliesis:
A) 2Cu(s)+ 2SO2(g)+5H2 O(g) 2CuSO4 5H2 O(s)
B) Cu(s) + SO4(g)+5H2 O(g)CuSO 4 5H2 O(s)
C) Cu(s) + S(s) +9/2O2 (g)+ 5H2(g) CuSO 4 5H2O(s)
D) Cu(s) + S(s) +5H2 O(g)+ 2O2 (g) CuSO 4 5H2 O(s)
E) Cu(s) + S(s) +5/9O2 (g)+ 5H2(g) CuSO 4 5H2O(s)
10) A6.55gsampleofaniline(C 6 H5 NH2,molarmass= 93.13g/mol)wascombustedinabombcalorimeter.If
thetemperatureroseby32.9C,usetheinformationbelowtodeterminetheheatcapacityofthecalorimeter.
4C6 H5 NH2 (l)+ 35O2 (g)24CO2 (g)+ 14H 2 O(g)+ 4NO2 (g) Hrxn=- 1.28x104 kJ
A) 5.94kJ/C
B) 97.3kJ/C
C) 38.9kJ/C
D) 12.8kJ/C
E) 6.84kJ/C
11) A5- ouncecupofraspberryyogurtcontains6.0gofprotein,2.0goffat,and26.9gofcarbohydrate.The
caloricvaluesforprotein,fat,andcarbohydrateare4.0,9.0,and4.0Cal./g,respectively.Thefoodenergy
valueofthiscupofyogurtis__________Cal.
A) 2.0 102
B) 1.5 102
C) 1.7 102
D) 3.3 102
E) 17
12) Howmuchenergyis evolvedduringthereactionof48.7gofAl,accordingtothereactionbelow?Assume
thatthereisexcessFe2 O3 .
Fe 2 O3 (s)+2Al(s)Al2 O3 (s)+2Fe(s)
A) 769kJ
B) 241kJ
C) 207kJ
Hrxn=- 852kJ
D) 415kJ
E) 130kJ
Paper:
CHEM 1310 University I Chemistry: Intro. to Phys. Chem.
Page: 4 of
7
13) WhichofCH4 (g),C2 H2 (g),andCH3 OH(l)providesthemostenergypergramuponcombustionandwhich
providestheleast?
CH4 (g ) + 2O2 (g ) CO2 (g ) + 2H2 O( l)
2C2 H2 (g ) + 5O2 (g ) 4CO 2 (g ) + 2H2 O( l)
2CH3 OH(l) + 3O2 (g ) 2CO 2 (g ) + 4H2 O( l)
H=- 890kJ
H=- 2599kJ
H=- 1453kJ
A) C2 H2 providesthemostenergypergramandCH 4 theleast.
B) CH4providesthemostenergypergramandCH 3OHtheleast.
C) C2 H2 providesthemostenergypergramandCH 3 OHtheleast.
D) CH4providesthemostenergypergramandC 2H2 theleast.
E) CH3OHprovidesthemostenergypergramandC 2 H2 theleast.
14) Forthereaction:2N2 O5(g)4NO2(g)+ O 2 (g)theratelawis:
[O 2 ]
=k[N2 O5 ]
t
At300K,thehalf- lifeis2.50 104 secondsandtheactivationenergyis103.3kJ/molO 2 .Atthetimewhen
N2 O5 isbeingconsumedatarateof1.2 10- 4 M/s,whatistherateatwhichNO 2 isbeingformed?
A) 2.4 10- 4M/s
B) 6.0 10- 5M/s
C) 4.8 10- 4M/s
D) 1.2 10- 4M/s
E) 3.0 10- 5M/s
15) Whatistheoverallorderofthefollowingreaction?
2NO(g)+H2 (g)N2 (g)+2H 2 O(g)
A) 2ndorder
B) 3rdorder
C) 1storder
D) 0thorder
E) Insufficientinformationgiven.
16) SO2Cl2decomposesinthegasphasebythereaction
SO2 Cl2 (g) SO2 (g)+ Cl2 (g)
ThereactionisfirstorderinSO2 Cl2 andtherateconstantis3.0 10- 6 s - 1 at600K.Avesselischargedwith
2.4atmof SO2 Cl2 at600K.Thepartialpressureof SO2 Cl2 at3.0 105 sis__________atm.
A) 1.4 105
B) 0.29
C) 0.76
D) 0.98
E) 2.2
Paper:
CHEM 1310 University I Chemistry: Intro. to Phys. Chem.
Page: 5 of
7
17) Determinetheratelawforthefollowingreactionusingthedataprovided.
CO(g)+Cl 2 (g)COCl2 (g)
[CO]i(M)
0.25
0.25
0.50
[Cl2 ]i(M)
0.40
0.80
0.80
InitialRate(M- 1 s - 1 )
0.696
1.97
3.94
A) Rate=18M- 3/2s - 1[CO]2[Cl2]1/2
B) Rate=36M- 1.8s -1 [CO][Cl2 ]2.8
C) Rate=11M- 3/2s - 1[CO][Cl2]3/2
D) Rate=17M- 2s - 1[CO][Cl2]2
E) Rate=4.4M-1/2s -1 [CO][Cl2 ]1/2
18) Thesecond-orderdecompositionofHIhasarateconstantof1.80x10 -3 M-1 s -1 .HowmuchHIremains
after27.3siftheinitialconcentrationofHIis4.78M?
A) 2.20M
B) 2.39M
C) 4.55M
D) 3.87M
E) 0.258M
19) If1.0gramofanisotopehasahalf - lifeof15hours,thehalf -lifeofa0.50gramsampleofthesameisotopeis:
A) 3.75hours
B) 7.5hours
C) 60hours
D) 15hours
E) 30hours
20) Theageofanancienttreetrunkisestimatedusingradiocarbondating.IfthetrunkhasaC - 14decayrate
thatis34%ofwhatitisinlivingplants,howoldisthetrunk?Thehalf - lifeofC- 14is5730years.
A) 2.9 104 years
B) 1.7 102 years
C) 8.9 103 years
D) 5.3 103 years
E) 1.9 104 years
21) Thereactionofcarbonmonoxidewithnitrogendioxidehasarateconstantof0.028at300 Cand1.3at400C.
Whatistheactivationenergyofthisreaction?
A) 14.7kJ/mol
B) 197kJ/mol
C) 38.3kJ/mol
D) 123kJ/mol
E) Insufficientinformationgiven.
Paper:
CHEM 1310 University I Chemistry: Intro. to Phys. Chem.
Page: 6 of
7
22) Whichenergydifferenceintheenergyprofilebelowcorrespondstotheactivationenergyforthereverse
reaction?
A) x
C) y- x
B) y
D) x+ y
E) x- y
23) ChoosetheINCORRECTstatement.
A) Therate- determiningstepistheslowstep.
B) Areactionintermediateisproducedandusedupduringthereaction.
C) Areactionintermediatehasfullyformedbonds.
D) Anactivatedcomplexisatransitorychemicalspecieswhichexistsatthetopofanactivationenergy
barrier.
E) Atransitionstateandareactionintermediatearethesame.
24) WhichofthefollowingstatementsisTRUE?
A) Acatalystraisestheactivationenergyofareaction.
B) Theadditionofahomogeneouscatalystdoesnotchangetheactivationenergyofagivenreaction.
C) Rateconstantsaretemperaturedependent.
D) Therateconstantdoesnotdependontheactivationenergyforareactionwheretheproductsarelower
E)
inenergythanthereactants.
Noneoftheabovearetrue.
25) Inachemicalsystematequilibrium,
A) theforwardandreversereactionsoccuratequalrate.
B) allofthereactantshavebeenconvertedtoproducts.
C) theforwardandreverserateconstantsarealwaysequal.
D) thereactantsandproductshavestoppedinteracting.
E) thechemicalreactionshaveallstopped.
26) Theequilibriumconstantforreaction(1)isK.Theequilibriumconstantforreaction(2)is__________.
(1)SO2 (g)+ (1/2) O2 (g)
(2)2SO3 (g)
A) -K2
SO3 (g)
2SO2 (g)+ O2 (g)
B) 1/(2K)
C) 1/K2
D) K2
E) 2K
Paper:
CHEM 1310 University I Chemistry: Intro. to Phys. Chem.
Page: 7 of
7
27) Theequilibrium-constantexpressionforthereaction
Ti(s)+ 2Cl2(g)
TiCl4(l)
isgivenby
[TiCl4 (l)]
A)
B)
C)
[Ti(s)][Cl2 (g)] 2
[TiCl4(l)]
[Cl2 (g)] 2
[Ti(s)][Cl2 (g)] 2
[TiCl4(l)]
D) [Cl2 (g)] -2
E)
[TiCl4 (l)]
[Ti(s)][Cl2 (g)]
28) Thereaction
H2 (g)+ I2 (g)2HI(g)
hasanequilibriumconstantKc=50at718K.Whatistheequilibriumconstant,K p,equalto,forthereaction
1
1
HI(g) H2 (g)+ I2 (g)?
2
2
A) 50
B) 25
C) 7.1
D) 0.14
E) 0.020
29) Considerthefollowingreactionatequilibrium.Whateffectwilladdingsomegraphitehaveonthesystem?
CO 2 (g)+C(graphite) 2CO(g)
A) Noeffectwillbeobservedsincegraphiteisnotincludedintheequilibriumexpression.
B) Thereactionwillshifttotheleftinthedirectionofreactants.
C) Theequilibriumconstantwilldecrease.
D) Theequilibriumconstantwillincrease.
E) Thereactionwillshifttotherightinthedirectionofproducts.
30) ForthereactionCO(g) +3H2 (g)H2O(g)+ CH4(g),Kc = 190at1000K.Avesselisfilledwiththesegases
suchthattheinitialconcentrationsare[CO] =0.025,[H 2 ] =0.045,[H 2 O]=0.025,and[CH 4 ] =0.046M. Which
ofthefollowingstatementsisTRUE?
A) Nothingwillhappenthereactionisatequilibrium.
B) Thereactionwillproceed towardproducts.
C) Thereactionwillproceedtowardreactants.
D) Addingacatalystwillcausetheequilibriumtoshifttotherightproducingmoreproducts.
E) Addingacatalystwillcausetheequilibriumtoshifttotheleftproducingmorereactants.
AnswerKey
Testname:2010CHEM1310MIDTERM
1) E
2) B
3) B
4) A
5) D
6) C
7) C
8) B
9) C
10) E
11) B
12) A
13) B
14) A
15) E
16) D
17) C
18) D
19) D
20) C
21) D
22) D
23) E
24) C
25) A
26) C
27) D
28) D
29) A
30) C