Practice Final Exam
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) What element is defined by the following information?
p+ = 17
n° = 20
e- = 17
A) neon
B) chlorine
C) calcium
1)
D) rubidium
E) oxygen
2) What does "X" represent in the following symbol?
235
X
92
A) uranium
B) copper
2)
C) tin
D) niobium
E) palladium
3) How many phosphorus atoms are contained in 158 kg of phosphorus?
3)
A) 2.95 × 1027 phosphorus atoms
B) 8.47 × 1024phosphorus atoms
C) 3.25 × 1028 phosphorus atoms
D) 1.18 × 1024 phosphorus atoms
E) 3.07 × 1027 phosphorus atoms
4) Determine the name for Cl2 O.
4)
A) chlorine oxide
B) dichloro monoxide
C) chlorate
D) chlorine (I) oxide
E) chlorine (II) oxide
5) How many N2 O4 molecules are contained in 76.3 g N2 O4 ? The molar mass of N2O4 is 92.02
g/mol.
A) 1.38 × 1024 N2O4 molecules
B) 5.54 × 1025 N2O4 molecules
C) 4.99 × 1023 N2O4 molecules
D) 4.59 × 1025 N2O4 molecules
E) 7.26 × 1023 N2O4 molecules
1
5)
6) Determine the limiting reactant (LR) and the mass (in g) of nitrogen that can be formed from 50.0 g
N2 O4 and 45.0 g N2 H4. Some possibly useful molar masses are as follows: N2 O4 = 92.02 g/mol,
N2 H4 = 32.05 g/mol.
N2O4 (l) + 2 N2H4(l)
6)
3 N2 (g) + 4 H2 O(g)
A) LR = N2H4, 59.0 g N2 formed
B) No LR, 45.0 g N2 formed
C) LR = N2O4, 45.7 g N2 formed
D) LR = N2H4, 13.3 g N2 formed
E) LR = N2O4, 105 g N2 formed
7) How many liters of a 0.0550 M KCl solution contain 0.163 moles of KCl?
A) 3.37 L
B) 1.12 L
C) 1.48 L
D) 8.97 L
7)
E) 2.96 L
8) Determine the theoretical yield of HCl if 60.0 g of BCl3 and 37.5 g of H2 O are reacted according to
the following balanced reaction. A possibly useful molar mass is BCl3 = 117.16 g/mol.
BCl3 (g) + 3 H2 O(l)
A) 187 g HCl
B) 25.3 g HCl
H3BO3(s) + 3 HCl(g)
C) 56.0 g HCl
D) 132 g HCl
E) 75.9 g HCl
9) What mass (in g) of AgCl is formed from the reaction of 75.0 mL of a 0.078 M AgC2H3O2 solution
with 55.0 mL of 0.109 M MgCl2 solution?
2 AgC2 H3 O2 (aq) + MgCl2 (aq)
A) 2.56 g
B) 1.72 g
C) 0.839 g
D) 1.70 g
and KOH are mixed.
K2 SO4 (s)
B) H2 2+(aq) + OH- (aq)
H2 (OH)2(l)
C) H+ (aq) + OH- (aq) + 2 K+(aq) + SO4 2- (aq)
D) H+ (aq) + OH- (aq)
9)
2 AgCl(s) + Mg(C2 H3O2 )2(aq)
E) 0.859 g
10) Give the net ionic equation for the reaction (if any) that occurs when aqueous solutions of H2 SO4
A) 2 K+ (aq) + SO4 2-(aq)
8)
H2 O(l) + K2 SO4 (s)
H2 O(l)
E) No reaction occurs.
2
10)
11) Give the complete ionic equation for the reaction (if any) that occurs when aqueous solutions of
MgSO3 and HI are mixed.
A) 2 H+(aq) + SO3 2- (aq)
H2 SO3 (s)
B) 2 H+(aq) + SO3 2- (aq) + Mg2+ (aq) + 2 I- (aq)
C) Mg2+(aq) + 2 I- (aq)
D) 2 H+(aq) + SO3 2- (aq)
11)
H2 SO3 (s) + MgI2 (aq)
MgI2 (s)
H2 O(l) + SO2 (g)
E) No reaction occurs.
12) Which of the gases in the graph below has the largest molar mass?
12)
A) A
B) B
C) C
D) D
E) There is not enough information to determine.
13) Determine the total pressure of all gases (at STP) formed when 50.0 mL of TNT (C3 H5 (NO3 )3 , d =
1.60 g/mL, molar mass = 227.10 g/mol) reacts according to the following reaction.
4 C3 H5 (NO3 )3(l)
A) 29.6 L
B) 57.2 L
6 N2(g) + O2(g) + 12 CO2(g) + 10 H2 O(g)
C) 175 L
3
D) 448 L
E) 4.93 L
13)
14) Determine the theoretical yield and the percent yield if 21.8 g of K2CO3 is produced from reacting
27.9 g KO2 with 29.0 L of CO2 (at STP). The molar mass of KO2 = 71.10 g/mol and K2 CO3 =
138.21 g/mol.
4 KO2(s) + 2 CO2 (g)
14)
2 K2CO3 (s) + 3 O2 (g)
A) 206 g, 10.6 % yield
B) 27.1 g, 80.4 % yield
C) 91.7 g, 23.8 % yield
D) 61.0 g, 35.7 % yield
E) 179 g, 12.2 % yield
15) A mixture of 0.220 moles CO, 0.350 moles H2 and 0.640 moles He has a total pressure of 2.95 atm.
15)
What is the pressure of CO?
A) 1.54 atm
B) 0.536 atm
C) 0.649 atm
D) 1.86 atm
E) 0.955 atm
16) Calculate the amount of heat (in kJ) required to raise the temperature of a 79.0 g sample of ethanol
from 298 K to 385 K. The specific heat capacity of ethanol is 2.42 J/g°C.
A) 16.6 kJ
B) 12.9 kJ
C) 28.4 kJ
D) 57.0 kJ
E) 73.6 kJ
17) A piece of iron (mass = 25.0 g) at 398 K is placed in a styrofoam coffee cup containing 25.0 mL of
water at 298 K. Assuming that no heat is lost to the cup or the surroundings, what will the final
temperature of the water be? The specific heat capacity of iron = 0.449 J/g°C and water = 4.18 J/g°C.
A) 388 K
B) 348 K
C) 308 K
D) 325 K
SO2Cl2 (g) + 2 H2O(l)
18)
2 HCl(g) + H2 SO4(l)
∆H rxn = ?
-364
SO2 Cl2(g)
H2 O(l)
HCl(g)
H2 SO4 (l)
A) +800. kJ
-286
-92
-814
B) +161 kJ
C) -422 kJ
4
D) -256 kJ
17)
E) 287 K
18) Use the ∆H°f information provided to calculate ∆H°rxn for the following:
∆H°f (kJ/mol)
16)
E) -62 kJ
19) Which of the following statements is TRUE?
19)
A) Part of the Bohr model proposed that electrons in the hydrogen atom are located in
"stationary states" or particular orbits around the nucleus.
B) The uncertainty principle states that we can never know both the exact location and speed of
an electron.
C) An orbital is the volume in which we are most likely to find an electron.
D) The emission spectrum of a particular element is always the same and can be used to identify
the element.
E) All of the above are true.
20) Which of the following transitions (in a hydrogen atom) represent emission of the longest
wavelength photon?
20)
A) n = 3 to n = 1
B) n = 3 to n = 4
C) n = 1 to n = 2
D) n = 5 to n = 4
E) n = 4 to n = 2
21) Each of the following sets of quantum numbers is supposed to specify an orbital. Which of the
following sets of quantum numbers contains an error?
21)
A) n = 4, l = 2, ml =0
B) n = 3, l = 0, ml =0
C) n = 3, l =3 , ml = -2
D) n = 2, l = 1 , ml = -1
E) n = 1, l = 0, ml =0
22) Each of the following sets of quantum numbers is supposed to specify an orbital. Choose the one
set of quantum numbers that does not contain an error.
A) n = 2, l = 2, ml =-1
B) n = 2, l = 2, ml =0
C) n = 4, l = 2, ml =+4
D) n = 4, l = 3, ml =-2
E) n = 3, l = 2, ml =-3
5
22)
23) Each of the following sets of quantum numbers is supposed to specify an orbital. Choose the one
set of quantum numbers that does not contain an error.
23)
A) n = 4, l = 0, ml =-1
B) n = 3, l = 1, ml = -2
C) n = 3, l = 2, ml =+3
D) n = 5, l = 3, ml =-3
E) n = 4, l = 4, ml =0
24) How many orbitals are contained in the third principal level (n=3) of a given atom?
A) 5
B) 3
C) 9
D) 18
24)
E) 7
25) Which of the following statements are TRUE?
25)
A) The angular momentum quantum number (l) describes the the size and energy associated
with an orbital.
B) The principal quantum number (n) describes the shape of an orbital.
C) The magnetic quantum number (ml ) describes the orientation of the orbital.
D) An orbital is the path that an electron follows during its movement in an atom.
E) All of the above are true.
26) Which of the following quantum numbers describes the shape of an orbital?
26)
A) magnetic quantum number
B) principal quantum number
C) spin quantum number
D) angular momentum quantum number
E) shrödinger quantum number
27) How many different values of ml are possible in the 4f sublevel?
A) 3
B) 1
C) 2
27)
D) 7
6
E) 5
28) Choose the orbital diagram that represents the ground state of N.
28)
A)
B)
C)
D)
E)
29) Choose the valence orbital diagram that represents the ground state of Zn.
A)
B)
C)
D)
E)
7
29)
30) Give the set of four quantum numbers that represent the last electron added (using the Aufbau
principle) to the Cl atom.
1
A) n = 3, l = 1, ml =0 , ms = +
2
B) n = 3, l =1 , ml = 0, ms = -
1
2
C) n = 2, l = 1, ml = 0, ms = -
1
2
D) n = 3, l = 0, ml = 0, ms = -
1
2
E) n = 3, l = 1, ml = 1, ms = +
1
2
31) Give the set of four quantum numbers that represent the electron gained to form the Br ION from
the Br atom.
1
A) n = 4, l = 0, ml = 1, ms = +
2
B) n = 4, l = 1, ml = 1, ms = -
31)
1
2
C) n = 4, l = 1, ml =-1 , ms = +
1
2
D) n = 3, l = 2, ml = 2, ms = +
1
2
E) n = 4, l = 2, ml = 1, ms = -
1
2
32) How many unpaired electrons are present in the ground state P atom?
A) 4
30)
B) 0
C) 1
D) 2
33) Choose the statement that is TRUE.
32)
E) 3
33)
A) Valence electrons are most difficult of all electrons to remove.
B) Core electrons are the easiest of all electrons to remove.
C) Core electrons efficiently shield outer electrons from nuclear charge.
D) Outer electrons efficiently shield one another from nuclear charge.
E) All of the above are true.
8
34) Place the following in order of increasing radius.
Ca2
S2
34)
Cl
A) Ca2 < Cl < S2
B) Ca2 < S2 < Cl
C) Cl < Ca2 < S2
D) Cl
< S2 < Ca 2
E) S2 < Cl < Ca 2
35) Place the following in order of increasing radius.
Br
Na
35)
Rb
A) Rb < Na < Br
B) Br < Rb < Na
C) Na < Rb < Br
D) Rb < Br < Na
E) Br < Na < Rb
36) Place the following in order of decreasing radius.
Te2
36)
O2
F
A) Te2 > F > O2
B) Te2 > O2 > F
C) F > Te2 > O2
D) O2 > F > Te2
E) F > O2 > Te2
37) What period 3 element is described by the following ionization energies (all in kJ/mol)?
IE1 = 1012
IE2 = 1900 IE3= 2910
A) P
B) S
IE4= 4960
IE5= 6270
C) Mg
IE6 = 22,200
D) Cl
9
E) Si
37)
38) Place the following in order of increasing IE1 .
N
F
38)
As
A) F < N < As
B) As < N < F
C) As < F < N
D) N < As < F
E) F < N < As
39) Place the following elements in order of increasing electronegativity.
K
Cs
39)
P
A) K < P < Cs
B) Cs < P < K
C) Cs < K < P
D) P < K < Cs
E) P < Cs < K
40) Place the following elements in order of increasing electronegativity.
Sr
N
40)
Na
A) Sr < Na < N
B) Sr < N < Na
C) Na < N < Sr
D) N < Na < Sr
E) N < Sr < Na
41) Using periodic trends, place the following bonds in order of increasing ionic character.
S-F
Se-F
O-F
A) O-F < S-F < Se-F
B) Se-F < S-F < O-F
C) O-F < Se-F < S-F
D) Se-F < O-F < S-F
E) S-F < Se-F < O-F
10
41)
42) Draw the Lewis structure for NO2 including any valid resonance structures. Which of the
following statements is TRUE?
A) The nitrite ion contains two N-O bonds that are equivalent to 1
42)
1
bonds.
2
B) The nitrite ion contains two N=O double bonds.
C) The nitrite ion contains two N-O single bonds.
D) The nitrite ion contains one N-O single bond and one N=O double bond.
E) None of the above are true.
43) Using Lewis structures and formal charge, which of the following ions is most stable?
OCN
ONC
NOC
A) ONC
B) NOC
C) OCN
D) None of these ions are stable according to Lewis theory.
E) All of these compounds are equally stable according to Lewis theory.
11
43)
44) Choose the best Lewis structure for SF4.
44)
A)
B)
C)
D)
E)
12
45) Choose the best Lewis structure for BF3 .
45)
A)
B)
C)
D)
E)
46) Determine the electron geometry (eg) and molecular geometry(mg) of BCl3.
A) eg=trigonal bipyramidal, mg= trigonal bipyramidal
B) eg=trigonal planar, mg=trigonal planar
C) eg=tetrahedral, mg=trigonal planar
D) eg=tetrahedral, mg=trigonal pyramidal
E) eg=trigonal planar, mg=bent
13
46)
47) Consider the molecule below. Determine the molecular geometry at each of the 2 labeled carbons.
47)
A) C1 = trigonal planar, C2= bent
B) C1 = bent, C2 = trigonal planar
C) C1 = tetrahedral, C2 = linear
D) C1 = trigonal pyramidal, C2 = see-saw
E) C1 = trigonal planar, C2 = tetrahedral
48) Consider the molecule below. Determine the hybridization at each of the 3 labeled atoms.
48)
A) 1=sp3, 2=sp3 , 3=sp2
B) 1=sp2, 2=sp3 , 3=sp2
C) 1=sp, 2=sp2 , 3=sp2
D) 1=sp2, 2=sp3 , 3=sp3
E) 1=sp3, 2=sp3 , 3=sp3
49) What is the strongest type of intermolecular force present in CHF3 ?
A) dispersion
B) hydrogen bonding
C) ion-dipole
D) dipole-dipole
E) None of the above
14
49)
50) What is the strongest type of intermolecular force present in NH2CH3 ?
50)
A) dipole-dipole
B) ion-dipole
C) disperion
D) hydrogen bonding
E) None of the above
51) Place the following compounds in order of increasing strength of intermolecular forces.
CO2
F2
51)
NH2 CH3
A) CO2 < NH2 CH3 < F2
B) F2 < NH2 CH3 < CO2
C) NH2 CH3 < CO2 < F2
D) NH2 CH3 < F2 < CO2
E) F2 < CO2 < NH2CH3
52) Assign the appropriate labels to the phase diagram shown below.
A) A = solid, B = gas, C = liquid, D = supercritical fluid
B) A = gas, B = solid, C = liquid, D = triple point
C) A = liquid, B = solid, C = gas, D = critical point
D) A = gas, B = liquid, C = solid, D = critical point
E) A = liquid, B = gas, C = solid, D = triple point
15
52)
53) Which of the following compounds will be most soluble in ethanol (CH3 CH2OH)?
53)
A) hexane (CH3CH2 CH2 CH2 CH2CH3 )
B) acetone (CH3 COCH3 )
C) trimethylamine (N(CH3 )3)
D) ethylene glycol (HOCH2CH2 OH)
E) None of these compounds should be soluble in methanol.
54) Calculate the molality of a solution formed by dissolving 27.8 g of LiI in 500.0 mL of water.
A) 0.254 m
B) 0.394 m
C) 0.241 m
D) 0.415 m
54)
E) 0.556 m
55) Choose the aqueous solution below with the highest freezing point. These are all solutions of
nonvolatile solutes and you should assume ideal van't Hoff factors where applicable.
55)
A) 0.200 m HOCH2 CH2 OH
B) 0.200 m Ca(ClO4 )2
C) 0.200 m K3PO3
D) 0.200 m Ba(NO3 )2
E) These all have the same freezing point.
56) Determine the vapor pressure of a solution at 25°C that contains 76.6 g of glucose (C6 H12O6 ) in
56)
250.0 mL of water. The vapor pressure of pure water at 25°C is 23.8 torr.
A) 22.9 torr
B) 72.9 torr
C) 70.8 torr
D) 23.1 torr
E) 7.29 torr
57) What is the overall order of the following reaction, given the rate law?
2X+3Y
A) 5th order
2Z
57)
Rate = k[X]1 [Y]2
B) 1st order
C) 2nd order
16
D) 0th order
E) 3rd order
58) Determine the rate law and the value of k for the following reaction using the data provided.
NO2(g) + O3 (g)
-1
(M s-1 )
NO3(g) + O 2(g)
[NO2 ]i (M)
[O3 ]i (M)
Initial Rate
0.10
0.10
0.25
0.33
0.66
0.66
1.42
2.84
7.10
58)
A) Rate = 43 M-1s-1 [NO2 ][O3 ]
B) Rate = 227 M-2.5s-1 [NO2 ][O3]2.5
C) Rate = 130 M-2 s-1 [NO2 ][O3 ]2
D) Rate = 1360 M-2.5s-1 [NO2 ]2.5[O3 ]
E) Rate = 430 M-2 s-1 [NO2 ]2[O3 ]
59) What data should be plotted to show that experimental concentration data fits a first-order
reaction?
59)
A) ln(k) vs. 1/T
B) 1/[reactant] vs. time
C) ln[reactant] vs. time
D) ln(k) vs. Ea
E) [reactant] vs. time
60) What data should be plotted to show that experimental concentration data fits a second-order
reaction?
60)
A) ln[reactant] vs. time
B) ln(k) vs. 1/T
C) ln(k) vs. Ea
D) 1/[reactant] vs. time
E) [reactant] vs. time
61) What data should be plotted to show that experimental concentration data fits a zeroth-order
reaction?
A) ln(k) vs. 1/T
B) ln[reactant] vs. time
C) [reactant] vs. time
D) 1/[reactant] vs. time
E) ln(k) vs. Ea
17
61)
62) The first-order decay of radon has a half-life of 3.823 days. How many grams of radon remain
after 7.22 days if the sample initially weighs 250.0 grams?
A) 4.21 g
B) 76.3 g
C) 67.5 g
D) 183 g
E) 54.8 g
63) Given the following proposed mechanism, predict the rate law for the overall reaction.
2NO2 + Cl2
Mechanism
NO2 + Cl2
NO2 + Cl
2NO 2Cl
62)
63)
(overall reaction)
NO2Cl + Cl slow
NO2 Cl
fast
A) Rate = k[NO2 ][Cl2 ]
B) Rate = k[NO2 ]2[Cl 2]
C) Rate = k[NO2 ][Cl]
D) Rate = k[NO2 Cl]2
E) Rate = k[NO2 Cl][Cl]
64) Which of the following statements are TRUE?
64)
A) A reaction quotient (Q) larger than the equilibrium constant (K) means that the reaction will
favor the production of more products.
B) The equilibrium constant for the forward reaction is equal to the equilibrium constant for the
reverse reaction.
C) Dynamic equilibrium occurs when the rate of the forward reaction equals the rate of the
reverse reaction.
D) Dynamic equilibrium indicates that the amount of reactants and products are equal.
E) All of the above are true.
65) Which of the following statements is FALSE?
65)
A) When K << 1, the reverse reaction is favored and the forward reaction does not proceed to a
great extent.
B) K >> 1 implies that the reaction is very fast at producing products.
C) When K 1, neither the forward or reverse reaction is strongly favored, and about the same
amount of reactants and products exist at equilibrium.
D) When K >> 1, the forward reaction is favored and essentially goes to completion.
E) All of the above statements are true.
18
66) The equilibrium constant is given for one of the reactions below. Determine the value of the
missing equilibrium constant.
H2 (g) + Br2 (g)
Kc = 3.8 × 104
Kc = ?
B) 5.3 × 10-5
C) 1.6 × 103
H2(g) + Br2(g)
2 HBr(g)
A) 1.9 × 104
2 HBr(g)
D) 2.6 × 10-5
E) 6.4 × 10-4
67) The equilibrium constant is given for two of the reactions below. Determine the value of the
missing equilibrium constant.
A(g) + B(g)
AB(g) + A(g)
2 A(g) + B(g)
A) 4.0
AB(g)
A2B(g)
A2 B(g)
B) 3.6
67)
Kc = 0.24
Kc = 3.8
Kc = ?
C) 16
D) 0.91
E) 0.63
68) Consider the following reaction at equilibrium. What effect will adding some C have on the
system?
CO2 (g) + C(graphite)
66)
68)
2 CO(g)
A) No effect will be observed since C is not included in the equilibrium expression.
B) The equilibrium constant will increase.
C) The reaction will shift to the left in the direction of reactants.
D) The equilibrium constant will decrease.
E) The reaction will shift to the right in the direction of products.
69) Consider the following reaction at equilibrium. What effect will increasing the temperature have
on the system?
Fe3 O4 (s) + CO(g)
3 FeO(s) + CO2(g)
∆H°= +35.9 kJ
A) The reaction will shift to the left in the direction of reactants.
B) The equilibrium constant will decrease.
C) No effect will be observed.
D) The equilibrium constant will increase.
E) The reaction will shift to the right in the direction of products.
19
69)
70) Which of the following acids is the STRONGEST? The acid is followed by its Ka value.
70)
A) HF, 3.5 × 10-4
B) HCHO2, 1.8 × 10-4
C) HClO2 , 1.1 × 10-2
D) HCN, 4.9 × 10-10
E) HNO2, 4.6 × 10-4
71) Which of the following bases is the STRONGEST? The base is followed by its Kb.
71)
A) CH3NH2 , 4.4 × 10-4
B) NH3 , 1.76 × 10-5
C) C5 H5 N, 1.7 × 10-9
D) (CH3CH2)2 NH, 8.6 × 10-4
E) C6 H5 NH2, 4.0 × 10-10
72) Determine the Kb for CN . The Ka for HCN is 4.9 × 10-10.
72)
A) 4.9 × 10-14
B) 2.0 × 10-5
C) 3.7 × 10-7
D) 1.4 × 10-5
E) 2.3 × 10-9
73) Determine the pH of a solution that is 0.15 M HClO2 (Ka = 1.1 x 10-2 ) and 0.15 M HClO (Ka = 2.9 ×
73)
10-8).
A) 1.45
B) 3.55
C) 9.82
D) 12.55
E) 4.18
74) Determine the pH of a 0.227 M C5 H5 N solution. The Kb of C5 H5 N is.1.7 × 10-9 .
A) 4.71
B) 10.14
C) 4.59
D) 9.41
20
74)
E) 9.29
75) Place the following in order of increasing acid strength.
HBrO2
HBrO3
HBrO
75)
HBrO4
A) HBrO < HBrO2 < HBrO3 < HBrO4
B) HBrO4 < HBrO2 < HBrO3 < HBrO
C) HBrO < HBrO4 < HBrO3 < HBrO2
D) HBrO2 < HBrO3 < HBrO4 < HBrO
E) HBrO2 < HBrO4 < HBrO < HBrO3
76) Which of the following solutions is a good buffer system?
76)
A) A solution that is 0.10 M HC2 H3 O2 and 0.10 M LiC2 H3 O2
B) A solution that is 0.10 M HF and 0.10 M NaC2 H3 O2
C) A solution that is 0.10 M NaOH and 0.10 M KOH
D) A solution that is 0.10 M HCl and 0.10 M NH4 +
E) None of the above are buffer systems.
77) Calculate the pH of a buffer that is 0.058 M HF and 0.058 M LiF. The Ka for HF is 3.5 × 10-4 .
A) 9.31
B) 4.69
C) 2.86
D) 3.46
77)
E) 10.54
78) If the pKa of HCHO2 is 3.74 and the pH of an HCHO2 /NaCHO2 solution is 3.89, which of the
78)
following is TRUE?
A) [HCHO2] > [NaCHO2 ]
B) [HCHO2] < [NaCHO2 ]
C) [HCHO2] >> [NaCHO2 ]
D) [HCHO2] = [NaCHO2 ]
E) It is not possible to make a buffer of this pH from HCHO2 and NaCHO2 .
79) When titrating a strong monoprotic acid and KOH at 25°C, the
A) pH will be less than 7 at the equivalence point.
B) titration will require more moles of base than acid to reach the equivalence point.
C) pH will be equal to 7 at the equivalence point.
D) pH will be greater than 7 at the equivalence point.
E) titration will require more moles of acid than base to reach the equivalence point.
21
79)
80) When titrating a weak monoprotic acid with NaOH at 25°C, the
80)
A) pH will be equal to 7 at the equivalence point.
B) pH will be greater than 7 at the equivalence point.
C) titration will require more moles of acid than base to reach the equivalence point.
D) titration will require more moles of base than acid to reach the equivalence point.
E) pH will be less than 7 at the equivalence point.
81) Give the expression for the solubility product constant for Ca3 (PO4 )2 .
A)
81)
[Ca2+]3 [PO43- ]2
Ca3 (PO4)2
B) [Ca2+ ]3 [PO4 3- ]2
C)
[Ca2+ ]2[PO4 3- ]3
Ca3(PO4 )2
D) [Ca2+ ]2 [PO4 3- ]3
E)
Ca3(PO4 )2
[Ca2+ ]3[PO4 3- ]2
82) Determine the molar solubility of MgCO3 in pure water. Ksp (MgCO3 ) = 6.82 × 10-6 .
82)
A) 3.41 × 10-6 M
B) 6.82 × 10-6 M
C) 3.25 × 10-4 M
D) 4.65 × 10-3 M
E) 2.61 × 10-3 M
83) Balance the following redox reaction if it occurs in acidic solution. What are the coefficients in front
of H2C2 O4 and H2 O in the balanced reaction?
MnO4 (aq) + H2C2 O4(aq)
Mn2+(aq) + CO2 (g)
A) H2 C2 O4 = 5, H2 O = 1
B) H2 C2 O4 = 1, H2 O = 4
C) H2 C2 O4 = 3, H2 O = 2
D) H2 C2 O4 = 1, H2 O = 1
E) H2 C2 O4 = 5, H2 O = 8
22
83)
84) Balance the following redox reaction if it occurs in acidic solution. What are the coefficients in front
of Zn and H+ in the balanced reaction?
Zn2+(aq) + NH4+ (aq)
84)
Zn(s) + NO3 (aq)
A) Zn = 2, H = 4
B) Zn = 4, H = 10
C) Zn = 3, H = 5
D) Zn = 1, H = 4
E) Zn = 1, H = 8
85) Determine the redox reaction represented by the following cell notation.
Mg(s) Mg 2+ (aq)
Cu2+(aq) Cu(s)
A) 2 Mg(s) + Cu2+(aq)
Cu(s) + 2 Mg2+(aq)
B) 3 Mg(s) + 2 Cu2+ (aq)
C) Cu(s) + Mg2+ (aq)
85)
2 Cu(s) + 3 Mg2+ (aq)
Mg(s) + Cu2+ (aq)
D) Mg(s) + Cu2+(aq)
Cu(s) + Mg2+(aq)
E) 2 Cu(s) + Mg2+(aq)
Mg(s) + 2 Cu2+ (aq)
86) What is the reducing agent in the redox reaction represented by the following cell notation?
Ni(s) Ni2+(aq)
A) Ni(s)
Ag+(aq) Ag(s)
B) Pt
C) Ag(s)
D) Ag+ (aq)
E) Ni2+ (aq)
87) What is undergoing oxidation in the redox reaction represented by the following cell notation?
Pb(s) Pb2+ (aq)
A) Pb2+ (aq)
C) H+ (aq)
D) Pb(s)
E) H2 (g)
88) Use the standard half-cell potentials listed below to calculate the standard cell potential for the
following reaction occurring in an electrochemical cell at 25°C. (The equation is balanced.)
Cl2 (g) + 2 e
2 Cl (aq)
Fe3+(aq) + 3 e
Fe(s)
A) +1.32 V
87)
H+(aq) H2(g) Pt
B) Pt
3 Cl2 (g) + 2 Fe(s)
86)
6 Cl (aq) + 2 Fe3+ (aq)
E° = +1.36 V
E° = -0.04 V
B) -1.32 V
C) +4.16 V
23
D) -1.40 V
E) +1.40 V
88)
89) Use the standard half-cell potentials listed below to calculate the standard cell potential for the
following reaction occurring in an electrochemical cell at 25 °C. (The equation is balanced.)
2 K(s) + I2 (s)
K+ (aq) + e
I2(s) + 2 e
2 K (aq) + 2 I (aq)
K (s)
2 I (aq)
A) +3.47 V
89)
E° = -2.93 V
E° = +0.54 V
B) +1.85 V
C) +5.32 V
D) +6.40 V
E) -5.32 V
90) Use the tabulated half-cell potentials to calculate the equilibrium constant (K) for the following
balanced redox reaction at 25°C.
Pb2+ (aq) + Cu(s)
90)
Pb(s) + Cu2+ (aq)
A) 1.26 × 10-16
B) 1.12 × 10-8
C) 8.89 × 107
D) 7.91 × 1015
E) 7.88 × 10-8
91) Calculate the cell potential for the following reaction that takes place in an electrochemical cell at
25°C.
Fe(s) Fe 3+ (aq, 0.0011 M)
A) +0.066 V
B) -0.036 V
Fe3+ (aq, 2.33 M) Fe(s)
C) -0.099 V
D) +0.20 V
E) 0.00 V
92) Nickel can be plated from aqueous solution according to the following half reaction. How long
would it take (in min) to plate 29.6 g of nickel at 4.7 A?
Ni2+(aq) + 2 e
91)
92)
Ni(s)
A) 5.9 × 102 min
B) 3.5 × 102 min
C) 4.8 × 102 min
D) 6.2 × 102 min
E) 1.7 × 102 min
93) Which of the following is the strongest reducing agent?
A) Sn4+(aq)
B) Sn2+(aq)
C) Cr3+(aq)
24
93)
D) Cr(s)
E) Sn(s)
94) Which of the following is the strongest oxidizing agent?
A) Au(s)
B) Br2 (l)
94)
D) Au3+(aq)
C) Ag(s)
E) Br (aq)
95) Above what temperature does the following reaction become nonspontaneous?
FeO(s) + CO(g)
CO2 (g) + Fe(s)
95)
∆H = -11.0 kJ; ∆S = -17.4 J/K
A) 298 K
B) 191 K
C) 632 K
D) This reaction is nonspontaneous at all temperatures.
E) This reaction is spontaneous at all temperatures.
96) Place the following in order of decreasing molar entropy at 298 K.
HCl
N 2 H4
96)
Ar
A) N2 H4 > Ar > HCl
B) Ar > HCl > N2 H4
C) Ar > N2 H4 > HCl
D) HCl > N2 H4 > Ar
E) N2 H4 > HCl > Ar
97) Calculate the ∆G°rxn using the following information.
∆H°f (kJ/mol)
S°(J/mol·K)
4 HNO3(g) + 5 N2 H4 (l)
-133.9
50.6
266.9
121.2
97)
7 N2(g) + 12 H2 O(l)
-285.8
191.6
A) -2.04 × 103 kJ
B) -2.96 × 103 kJ
C) +3.90 × 103 kJ
D) -3.15 × 103 kJ
E) +4.90 × 103 kJ
25
70.0
∆G°rxn = ?
98) Determine the equilibrium constant for the following reaction at 498 K.
2 Hg(g) + O2 (g)
2 HgO(s)
98)
∆H° = -304.2 kJ; ∆S° = -414.2 J/K
A) 5.34 × 10-11
B) 4.33 × 1021
C) 8.10 × 1031
D) 1.87 × 1010
E) 2.31 × 10-22
99) Choose the statement below that is TRUE.
99)
A) K > 1, ∆G°rxn is positive
B) K < 1, ∆G°rxn is negative
C) ∆Grxn = 0 at equilibrium
D) ∆G°rxn = 0 at equilibrium
E) None of the above statements are true.
100) Calculate ∆Grxn at 298 K under the conditions shown below for the following reaction.
CaCO3 (s)
CaO(s) + CO2 (g)
∆G° =+131.1 kJ
P(CO2) = 0.033 atm
A) -49.3 kJ
B) -8.32 kJ
C) +123 kJ
26
D) +43.3 kJ
E) +39.7 kJ
100)