14.For the redox reaction 2Fe2+ + Cl2 2Fe3+ + 2Cl which of the
following are the correct half-reactions?I.Cl2 + 2e 2Cl
II.Cl Cl + e
III.Cl2 2Cl + 2e
IV.Fe2+ Fe3+ + e
V.Fe2+ + e Fe3+
a)I and IVb)I and Vc)II and IVd)II and Ve)III and IVAns:a
Algorithm:No Chapter/Section:18.1 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:half-reaction15.What is the
oxidation state of Hg in Hg2Cl2?a)+2b)1c)2d)+1e)0Ans:d Algorithm:No
Chapter/Section:18.1 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:chemicalreactions
Keyword4:typesofchemicalreactions
Keyword5:oxidation-reductionreaction
Keyword6:assigningoxidationnumber
16.How many electrons are transferred in the following reaction?
2ClO3 + 12H+ + 10I 5I2 + Cl2 + 6H2Oa)12b)5c)2d)30e)10Ans:e
Algorithm:No Chapter/Section:18.1 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:half-reaction
Keyword5:balancingchemicalequation17.How many electrons are
transferred in the following reaction? Cd + 2HCl CdCl2 +
H2a)0b)1c)2d)4e)not enough information givenAns:c Algorithm:Yes
Chapter/Section:18.1 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:half-reaction
Keyword5:balancingoxidation-reductionreactionsConsider a galvanic
cell based in the reaction Fe2+ + Cr2O72 Fe3+ + Cr3+ in acidic
solution.21.What is the coefficient of Fe3+ in the balanced
equation?a)6b)2c)3d)4e)none of theseAns:a Algorithm:No
Chapter/Section:18.1 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:half-reaction
Keyword5:balancingoxidation-reductionreactions
Keyword6:half-reactionmethod22.Calculate the voltage of the
standard cell carrying out this reaction.a)0b)0.21 Vc)0.21 Vd)0.56
Ve)0.56 VAns:d Algorithm:No Chapter/Section:18.3 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells Keyword5:standard
cell emfs and standard electrode potentials
Keyword6:calculatingcellemfs23.Which energy conversion shown below
takes place in a galvanic cell?a)electrical to chemicalb)chemical
to electricalc)mechanical to chemicald)chemical to
mechanicale)mechanical to electricalAns:b Algorithm:No
Chapter/Section:18.2 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:voltaiccells24.Which of the following reactions is
possible at the anode of a galvanic cell?a)Zn Zn2+ + 2eb)Zn2+ + 2e
Znc)Zn2+ + Cu Zn + Cu2+d)Zn + Cu2+ Zn2+ + Cue)two of theseAns:a
Algorithm:No Chapter/Section:18.2 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells
Keyword5:constructionofvoltaiccells25.Which of the following is
true for the cell shown here? Zn(s)Zn2+(aq) Cr3+(aq) Cr(s)a)The
electrons flow from the cathode to the anode.b)The electrons flow
from the zinc to the chromium.c)The electrons flow from the
chromium to the zinc.d)The chromium is oxidized.e)The zinc is
reduced.Ans:b Algorithm:No Chapter/Section:18.2 Difficulty:Moderate
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells
Keyword5:constructionofvoltaiccells26.The anode in a voltaic cell
and in an electrolytic cell isa)positive in both cellsb)the site of
oxidation and of reduction, respectivelyc)the site of reduction and
of oxidation, respectivelyd)the site of oxidation in both
cellse)the site of reduction in both cellsAns:d Algorithm:No
Chapter/Section:18.2 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:voltaiccells Keyword5:constructionofvoltaiccells
difficulty:easy27.Which statement is always true of the cathode in
an electrochemical cell?a)It is considered the negative
electrode.b)It is considered the positive electrode.c)Reduction
occurs here.d)Metal is plated out here.e)Negative ions flow toward
the cathode.Ans:c Algorithm:No Chapter/Section:18.2 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells
Keyword5:constructionofvoltaiccells difficulty:moderate28.A strip
of copper is placed in a 1 M solution of copper nitrate and a strip
of silver is placed in a 1 M solution of silver nitrate. The two
metal strips are connected to a voltmeter by wires and a salt
bridge connects the solutions. The following standard reduction
potentials apply:Ag+(aq) + e Ag(s) = +0.80 V
Cu2+(aq) + 2e Cu(s) = +0.34 V
Which of the following statements is false?a)Electrons flow in
the external circuit from the copper electrode to the silver
electrode.b)The silver electrode increases in mass as the cell
operates.c)There is a net general movement of silver ions through
the salt bridge to the copper half-cell.d)Negative ions pass
through the salt bridge from the silver half-cell to the copper
half-cell.e)Some positive copper ions pass through the salt bridge
from the copper half-cell to the silver half-cell.Ans:c
Algorithm:No Chapter/Section:18.3 Difficulty:Moderate
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells
Keyword5:constructionofvoltaiccells29.You are told that metal X is
a better reducing agent than metal Y. This must mean that:a)X+ is a
better oxidizing agent than Y+.b)X+ is a better reducing agent than
Y+.c)Y is a better oxidizing agent than X.d)Y+ is a better reducing
agent than X+.e)Y+ is a better oxidizing agent than X+.Ans:e
Algorithm:No Chapter/Section:18.3 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells Keyword5:standard
cell emfs and standard electrode potentials Keyword6:strength of
oxidizing and reducing agents30.Which of the following species
cannot function as an oxidizing
agent?a)S(s)b)NO3(aq)c)Cr2O72(aq)d)I(aq)e)MnO4(aq)Ans:d
Algorithm:No Chapter/Section:18.3 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells Keyword5:standard
cell emfs and standard electrode potentials31.Which of the
following is the strongest oxidizing agent? MnO4 + 4H+ + 3e MnO2 +
2H2O = 1.68 V
I2 + 2e 2I = 0.54 V
Zn2+ + 2e Zn = 0.76 V
a)MnO4b)I2c)Zn2+d)Zne)MnO2Ans:a Algorithm:No
Chapter/Section:18.3 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:voltaiccells Keyword5:standard cell emfs and standard
electrode potentials Keyword6:strength of oxidizing and reducing
agents32.Which metal, Al or Ni could reduce Zn2+ to Zn(s) if placed
in a Zn2+(aq) solution?Zn2+ + 2e Zn = 0.76 V
Al3+ + 3e Al = 1.66 V
Ni2+ + 2e Ni = 0.23 V
a)Alb)Nic)Both Al and Ni would work.d)Neither Al nor Ni would
work.e)Cannot be determined.Ans:a Algorithm:No Chapter/Section:18.3
Difficulty:Easy Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells Keyword5:standard
cell emfs and standard electrode potentials Keyword6:tabulating
standard electrode potentials
33.Which of the following is the best reducing agent? Cl2 + 2e
2Cl = 1.36 V
Mg2+ + 2e Mg = 2.37 V
2H+ + 2e H2 = 0.00 V
a)Cl2b)H2c)Mgd)Mg2+e)Cl-Ans:c Algorithm:No Chapter/Section:18.3
Difficulty:Easy Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells Keyword5:standard
cell emfs and standard electrode potentials Keyword6:strength of
oxidizing and reducing agents34.Consider the galvanic cell shown
below (the contents of each half-cell are written beneath each
compartment):
0.50 M Br2 0.20 M Cr3+ 0.10 M BrThe standard reduction
potentials are as follows:Cr3+(aq) + 3e Cr(s) = 0.725 VBr2(aq) + 2e
2Br(aq) = +1.090 VWhat is for this cell?a)1.815 Vb)0.365 Vc)0.365
Vd)4.720 Ve)1.320 VAns:a Algorithm:Yes Chapter/Section:18.3
Difficulty:Easy Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells Keyword5:standard
cell emfs and standard electrode potentials
Keyword6:calculatingcellemfs
35.Consider the galvanic cell shown below (the contents of each
half-cell are written beneath each compartment):
0.50 M Br2 0.20 M Cr3+ 0.10 M BrThe standard reduction
potentials are as follows:Cr3+(aq) + 3e Cr(s) = -0.73 VBr2(aq) + 2e
2Br(aq) = +1.09 V
Which of the following statements about this cell is
false?a)This is a galvanic cell.b)Electrons flow from the Pt
electrode to the Cr electrode.c)Reduction occurs at the Pt
electrode.d)The cell is not at standard conditions.e)To complete
the circuit, cations migrate into the left half-cell and anions
migrate into the right half-cell from the salt bridge.Ans:b
Algorithm:No Chapter/Section:18.3 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells
Keyword5:constructionofvoltaiccells36.Refer to the galvanic cell
below (the contents of each half-cell are written beneath each
compartment):
0.10 M MnO4 0.40 M Cr3+0.20 M Mn2+ 0.30 M Cr2O720.010 M H+ 0.010
M H+The standard reduction potentials are as follows:MnO4 + 8H+ +
5e Mn2+ + 4H2O, = 1.507 VCr2O72 + 14H+ + 6e 2Cr3+ + 7H2O, = 1.330
V
What is the value of
cell?a)0.177b)2.837c)0.177d)0.677e)6.205Ans:c Algorithm:Yes
Chapter/Section:18.5 Difficulty:Moderate Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:voltaiccells Keyword5:dependenceofemfonconcentration
Keyword6:Nernstequation
Use the following to answer questions 37-44:
Refer to the galvanic cell below (the contents of each half-cell
are written beneath each compartment):
0.10 M MnO4 0.40 M Cr3+0.20 M Mn2+ 0.30 M Cr2O720.010 M H+ 0.010
M H+The standard reduction potentials are as follows:MnO4 + 8H+ +
5e Mn2+ + 4H2O, = 1.51 VCr2O72 + 14H+ + 6e 2Cr3+ + 7H2O, = 1.33
V37.When current is allowed to flow, which species is
oxidized?a)Cr2O72b)Cr3+c)MnO4d)Mn2+e)H+Ans:b Algorithm:No
Chapter/Section:18.3 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:voltaiccells Keyword5:constructionofvoltaiccells38.When
current is allowed to flow, which species is
reduced?a)Cr2O72b)Cr3+c)MnO4d)Mn2+e)H+Ans:c Algorithm:No
Chapter/Section:18.3 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:voltaiccells Keyword5:constructionofvoltaiccells
39.What is the oxidation state of Cr in
Cr2O72?a)+7b)+6c)+12d)1e)2Ans:b Algorithm:No Chapter/Section:18.1
Difficulty:Easy Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:chemicalreactions Keyword4:typesofchemicalreactions
Keyword5:oxidation-reductionreaction
Keyword6:assigningoxidationnumber40.What is the value of Q, the
reaction quotient, for this cell reaction?a)6.7 1040b)1.5 1041c)1.5
104d)6.7 103e)none of theseAns:b Algorithm:No Chapter/Section:18.5
Difficulty:Moderate Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells
Keyword5:dependenceofemfonconcentration41.In which direction do
electrons flow in the external circuit?a)left to rightb)right to
leftc)no current flows; the cell is at equilibriumd)cannot be
determined.e)none of theseAns:b Algorithm:No Chapter/Section:18.3
Difficulty:Easy Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells
Keyword5:constructionofvoltaiccells45.A cell is set up with copper
and lead electrodes in contact with CuSO4(aq) and Pb(NO3)2(aq),
respectively, at 25C. The standard reduction potentials are: Pb2+ +
2e Pb = 0.13 V Cu2+ + 2e Cu = +0.34 VIf the Pb2+ and Cu2+ are each
1.0 M, the potential of the cell, in volts, is:a)0.47 Vb)0.92
Vc)0.22 Vd)0.58 Ve)none of theseAns:a Algorithm:No
Chapter/Section:18.3 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:voltaiccells Keyword5:standard cell emfs and standard
electrode potentials Keyword6:calculatingcellemfs46.Consider an
electrochemical cell with a zinc electrode immersed in 1.0 M Zn2+
and a silver electrode immersed in 1.0 M Ag+.Zn2+ + 2e Zn = 0.755
VAg+ + e Ag = 0.800 VCalculate for this cell.a)0.045 Vb)0.045
Vc)1.555 Vd)1.555 Ve)none of theseAns:c Algorithm:Yes
Chapter/Section:18.3 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:voltaiccells Keyword5:standard cell emfs and standard
electrode potentials Keyword6:calculatingcellemfs
47.The galvanic cell described by Zn(s)Zn2+(aq)Cu2+(aq)Cu(s) has
a standard cell potential of 1.101 volts. Given that Zn(s) Zn2+(aq)
+ 2e has an oxidation potential of 0.762 volts, determine the
reduction potential for .a)1.863 Vb)1.863 Vc)0.339 Vd)0.339 Ve)none
of theseAns:d Algorithm:Yes Chapter/Section:18.3
Difficulty:Moderate Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells Keyword5:standard
cell emfs and standard electrode potentials
48.The following question refers to a galvanic cell that
utilizes the following reaction (unbalanced):(AuCl4)(aq) + Cu(s)
Au(s) + Cl(aq) + Cu2+(aq)Given the following information, determine
the standard cell potential:SpeciesStandard Reduction Potential
(V)
Au3+(aq)1.4980
Cu2+(aq)-0.3391
a)1.1589 Vb)1.8371 Vc)3.8158 Vd)0.8198 Ve)4.1549 VAns:a
Algorithm:Yes Chapter/Section:18.3 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells Keyword5:standard
cell emfs and standard electrode potentials
Keyword6:calculatingcellemfs49.Choose the correct statement given
the following information: Fe3+(aq) + e Fe2+(aq) = 0.77 V
Fe(CN)63(aq) + e Fe(CN)64(aq) = 0.36 Va)Fe2+(aq) is more likely to
be oxidized than Fe2+ complexed to CN.b)Fe3+(aq) is more likely to
be reduced than Fe3+ complexed to CN.c)Both A and B are
true.d)Complexation of Fe ions with CN has no effect on their
tendencies to become oxidized or reduced.e)None of these is
true.Ans:b Algorithm:No Chapter/Section:18.3 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells Keyword5:standard
cell emfs and standard electrode potentials Keyword6:strength of
oxidizing and reducing agents50.The following question refers to
the following system:3Ag(s) + NO3(aq) + 4H+(aq) 3Ag+(aq) + NO(g) +
2H2O(l)Anode reaction:Ag Ag+(aq) + e = 0.7990 VCathode
reaction:NO3(aq) + 4H+(aq) + 3e NO(g) + 2H2O(l) = 0.9639 VDetermine
the standard cell potential.a)1.7629 Vb)0.1649 Vc)2.0927 Vd)3.5258
Ve)0.5876 VAns:b Algorithm:Yes Chapter/Section:18.3 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells Keyword5:standard
cell emfs and standard electrode potentials
Keyword6:calculatingcellemfs
51.Which of the following would be the best oxidizing
agent?a)Cl2b)Fec)Nad)Na+e)FAns:a Algorithm:No Chapter/Section:18.3
Difficulty:Easy Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells Keyword5:standard
cell emfs and standard electrode potentials Keyword6:strength of
oxidizing and reducing agents52.Copper will spontaneously reduce
which of the following?a)Fe2+ and Ag+b)Fe2+c)Ag+d)Al3+e)Fe2+ and
Al3+Ans:c Algorithm:No Chapter/Section:18.3 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells Keyword5:standard
cell emfs and standard electrode potentials Keyword6:tabulating
standard electrode potentials53.Determine the standard potential, ,
of a cell that employs the reaction:Fe + Cu2+ Cu + Fe2+.Reaction
(volts)
Fe2++ 2e Fe0.440
Cu2++ 2e Cu+0.340
a)0.100b)0.780c)0.100d)0.780e)0.200Ans:d Algorithm:Yes
Chapter/Section:18.3 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:voltaiccells Keyword5:standard cell emfs and standard
electrode potentials Keyword6:calculatingcellemfs54.Of Sn2+, Ag+,
and/or Zn2+, which could be reduced by Cu?a)Sn2+b)Ag+c)Zn2+d)Two of
them could be reduced by Cu.e)All of them could be reduced by
Cu.Ans:b Algorithm:No Chapter/Section:18.3 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells Keyword5:standard
cell emfs and standard electrode potentials Keyword6:tabulating
standard electrode potentials55.You wish to plate out zinc metal
from a zinc nitrate solution. Which metal, Al or Ni, could you
place in the solution to accomplish this?a)Alb)Nic)Both Al and Ni
would work.d)Neither Al nor Ni would work.e)Cannot be
determined.Ans:a Algorithm:No Chapter/Section:18.3 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells Keyword5:standard
cell emfs and standard electrode potentials Keyword6:tabulating
standard electrode potentials56.Which of the following is the best
reducing agent?a)Cl2b)H2c)Mgd)Mg2+e)ClAns:c Algorithm:No
Chapter/Section:18.3 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:voltaiccells Keyword5:standard cell emfs and standard
electrode potentials Keyword6:strength of oxidizing and reducing
agents65.Which of the following statements is true concerning the
electrochemical cell depicted below?Ca | Ca2+(aq) || Mn2+(aq) |
MnCa2+(aq) + 2e Ca(s); = 2.87 VMn2+(aq) + 2e Mn(s); = 1.19 Va)The
cell reaction is spontaneous with a standard cell potential of 1.68
V.b)The cell reaction is spontaneous with a standard cell potential
of 4.06 V.c)The cell reaction is nonspontaneous with a standard
cell potential of 1.68 V.d)The cell reaction is nonspontaneous with
a standard cell potential of 4.06 V.e)The cell is at
equilibrium.Ans:a Algorithm:Yes Chapter/Section:18.3
Difficulty:Moderate Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells Keyword5:standard
cell emfs and standard electrode potentials
Keyword6:calculatingcellemfs66.Which of the following statements is
true concerning the electrochemical cell depicted below?Sr |
Sr2+(aq) || Rb+(aq) | RbSr2+(aq) + 2e Sr(s); = 2.90 VRb+(aq) + e
Rb(s); = 2.98 Va)The cell reaction is spontaneous with a standard
cell potential of 0.08 V.b)The cell reaction is nonspontaneous with
a standard cell potential of 5.88 V.c)The cell reaction is
nonspontaneous with a standard cell potential of 0.08 V.d)The cell
reaction is spontaneous with a standard cell potential of 5.88
V.e)The cell is at equilibrium.Ans:c Algorithm:Yes
Chapter/Section:18.3 Difficulty:Moderate Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:voltaiccells Keyword5:standard cell emfs and standard
electrode potentials Keyword6:calculatingcellemfs
67.The reduction potentials for Au3+ and Ni2+ are as
follows:Au3+ + 3e Au, = +1.50 VNi2+ + 2e Ni, = 0.232 V
Calculate G (at 25C) for the reaction:2Au3+ + 2Ni 3Ni2+ +
2Aua)1.00 103 kJb)7.34 102 kJc)7.34 102 kJd)1.67 102 kJe)1.00 103
kJAns:e Algorithm:Yes Chapter/Section:18.4 Difficulty:Moderate
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells74.Determine G for a
cell that utilizes the following reaction:
Cl2(g) + 2Br(aq) 2Cl(aq) + Br2(l)The standard reduction for the
chlorine gas is 1.360 volts and the standard reduction for the
bromine liquid is about 1.076 volts.a)470 kJb)27.4 kJc)235 kJd)54.8
kJe)24.3 kJAns:d Algorithm:Yes Chapter/Section:18.4
Difficulty:Moderate Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells77.A common car
battery consists of six identical cells, each of which carries out
the reaction:
Pb + PbO2 + 2HSO4 + 2H+ 2PbSO4 + 2H2OThe value of for such a
cell is 2.041 V. Calculate G at 25 C for the reaction.a)196.9
kJb)98.46 kJc)393.9 kJd)787.7 kJe)590.8 kJAns:c Algorithm:Yes
Chapter/Section:18.4 Difficulty:Moderate Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:voltaiccells78.What is G for the following electrochemical
equation? (red(Na+/Na) = 2.710 V, red(Zn2+/Zn) = 0.762 V)2Na(s) +
Zn2+(aq) 2Na+(aq) + Zn(s)a)376 kJ/molb)188 kJ/molc)376 kJ/mold)752
kJ/mole)752 kJ/molAns:c Algorithm:Yes Chapter/Section:18.4
Difficulty:Moderate Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells107.Which of the
following statements is true concerning the electrochemical cell
described below at 25oC?Cu | Cu2+(0.935 M) || Cu2+(0.982 M) |
CuCu2+(aq) + 2e Cu(s); = 0.34 Va)The cell reaction is spontaneous
with a cell potential of 1.10 mV.b)The cell reaction is spontaneous
with a cell potential of 0.630 mV.c)The cell reaction is
nonspontaneous with a cell potential of 0.630 mV.d)The cell
reaction is nonspontaneous with a cell potential of 1.10 mV.e)The
cell reaction is spontaneous with a cell potential of 0.34 V.Ans:b
Algorithm:Yes Chapter/Section:18.5 Difficulty:Difficult
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells
Keyword5:dependenceofemfonconcentration
Keyword6:Nernstequation108.What is the potential at 25C for the
following cell?CrCr3+(0.015 M)Ag+(0.00010 M)AgCr3+ + 3e Cr = 0.73
VAg+ + e Ag = 0.80 Va)2.09 Vb)1.33 Vc)0.95 Vd)1.73 Ve)1.49 VAns:b
Algorithm:Yes Chapter/Section:18.5 Difficulty:Moderate
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells
Keyword5:dependenceofemfonconcentration
Keyword6:Nernstequation109.T F Concentration cells work because
standard reduction potentials are dependent on
concentration.Ans:False Algorithm:No Chapter/Section:18.5
Difficulty:Easy Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells
Keyword5:dependenceofemfonconcentration110.Consider the
hydrogenoxygen fuel cell where:H2(g) + O2(g) H2O(l) G = 237.18
kJ/mol H2Which of the following statements is true?a)At standard
conditions, the maximum work the fuel cell could do on the
surroundings is 237.18 kJ/mol.b)In the real world, the actual
amount of useful work the cell can do is less than 237.18 kJ.c)More
energy is dissipated as waste heat in the fuel cell than in the
reversible pathway.d)A, B, and C are all true.e)A, B, and C are all
false.Ans:d Algorithm:No Chapter/Section:18.6 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:voltaiccells115.How many
faradays are involved in conversion of a mole of Cu2O to
CuO?a)1b)2c)3d)4e)5Ans:a Algorithm:Yes Chapter/Section:18.8
Difficulty:Easy Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis116.How many moles of electrons
are produced from a current of 17.6 A in 3.00 hours?
a)5.47 104 molb)1.97 molc)52.8 mold)3.35 mol
e)9.33 103 molAns:b Algorithm:Yes Chapter/Section:18.8
Difficulty:Easy Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis
117.A common car battery consists of six identical cells each of
which carries out the reaction:Pb + PbO2 + 2HSO4 + 2H+ 2PbSO4 +
2H2OSuppose that in starting a car on a cold morning a current of
125 amperes is drawn for 22.9 seconds from a cell of the type
described above. How many grams of Pb would be consumed? (The
atomic weight of Pb is 207.19.)a)6.15 gb)3.07 gc)5.86 103 gd)1.97
104 ge)1.48 102 gAns:b Algorithm:Yes Chapter/Section:18.8
Difficulty:Moderate Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis
Use the following to answer questions 118-119:
An antique automobile bumper is to be chrome plated. The bumper,
which is dipped into an acidic Cr2O72 solution, serves as a cathode
of an electrolytic cell. The atomic mass of Cr is 51.996; 1 faraday
= 96,485 coulombs.118.If oxidation of H2O occurs at the anode, how
many moles of oxygen gas will evolve for every 145 grams of Cr(s)
deposited?a)4.18b)0.697c)16.7d)11.2e)3.72Ans:a Algorithm:Yes
Chapter/Section:18.8 Difficulty:Difficult Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis119.If the current is 10.0
amperes, how long will it take to deposit 137 grams of Cr(s) onto
the bumper?a)7.06 hb)1.77 daysc)70.6 mind)2.63 mine)2 mo, 25 days,
14 h, and 6 sAns:b Algorithm:Yes Chapter/Section:18.8
Difficulty:Easy Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis
120.Copper is electroplated from CuSO4 solution. A constant
current of 3.70 amp is applied by an external power supply. How
long will it take to deposit 1.00 102 g of Cu? The atomic mass of
copper is 63.546.a)22.8 hb)11.4 minc)1.75 daysd)11.10 se)3.26
hAns:a Algorithm:Yes Chapter/Section:18.8 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis121.What quantity of charge is
required to reduce 21.4 g of CrCl3 to chromium metal? (1 faraday =
96,485 coulombs)a)1.30 104 Cb)3.91 104 Cc)6.19 102 Cd)2.06 102
Ce)none of theseAns:b Algorithm:Yes Chapter/Section:18.8
Difficulty:Easy Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis122.Electrolysis of a molten
salt with the formula MCl, using a current of 3.86 amp for 16.2
min, deposits 1.52 g of metal. Identify the metal. (1 faraday =
96,485 coulombs)a)Lib)Nac)Kd)Rbe)CaAns:c Algorithm:No
Chapter/Section:18.8 Difficulty:Moderate Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:electrolyticcells Keyword5:electrolysisofmoltensalts123.If
a constant current of 4.3 amperes is passed through a cell
containing Cr3+ for 1.0 hour, how many grams of Cr will plate out
onto the cathode? (The atomic mass of Cr is 51.996.)a)8.3 gb)7.7
104 gc)2.8 gd)25 ge)5.3 102 gAns:c Algorithm:Yes
Chapter/Section:18.8 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis124.If an electrolysis plant
operates its electrolytic cells at a total current of 1.1 106 amp,
how long will it take to produce one metric ton (one million grams)
of Mg(s) from seawater containing Mg2+? (1 faraday = 96,485
coulombs)a)2.0 hb)2.0 daysc)60 mind)1.0 he)0.50 yearAns:a
Algorithm:Yes Chapter/Section:18.8 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis125.Nickel is electroplated
from a NiSO4 solution. A constant current of 2.03 amp is applied by
an external power supply. How long will it take to deposit 100. g
of Ni? The atomic mass of Ni is 58.69.a)45.0 hb)22.5 hc)49.3
mind)150.0 se)2.95 sAns:a Algorithm:Yes Chapter/Section:18.8
Difficulty:Easy Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis126.A solution of MnO42 is
electrolytically reduced to Mn3+. A current of 7.32 amp is passed
through the solution for 15.0 minutes. What is the number of moles
of Mn3+ produced in this process? (1 faraday = 96,485
coulombs)a)0.0683b)0.205c)3.79 104d)0.0228e)1.52 103Ans:d
Algorithm:Yes Chapter/Section:18.8 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis127.How many seconds would it
take to deposit 17.3 g of Ag (atomic mass = 107.87) from a solution
of AgNO3 using a current of 10.00 amp?a)3.09 103 sb)7.74 102
sc)4.64 103 sd)1.55 103 se)5.16 102 sAns:d Algorithm:Yes
Chapter/Section:18.8 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis128.Gold (atomic mass = 197.0)
is plated from a solution of chloroauric acid, HAuCl4; it deposits
on the cathode. Calculate the time it takes to deposit 0.65 gram of
gold, passing a current of 0.10 amperes. (1 faraday = 96,485
coulombs)a)27 hoursb)2.7 hoursc)53 minutesd)18 minutese)none of
theseAns:b Algorithm:Yes Chapter/Section:18.8 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis129.An unknown metal (M) is
electrolyzed. It took 74.1 s for a current of 2.00 amp to plate
0.107 g of the metal from a solution containing M(NO3)3. Identify
the metal.a)Lab)Bic)Gad)Cue)RhAns:b Algorithm:No
Chapter/Section:18.8 Difficulty:Moderate Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis130.Gold is produced
electrochemically from an aqueous solution of Au(CN)2 containing an
excess of CN. Gold metal and oxygen gas are produced at the
electrodes. How many moles of O2 will be produced during the
production of 1.00 mole of gold?a)0.25b)0.50c)1.00d)3.56e)4.00Ans:a
Algorithm:No Chapter/Section:18.8 Difficulty:Difficult
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:electrolyticcells
Keyword5:aqueouselectrolysis131.What mass of Ni(s) may be deposited
from an aqueous NiCl2 solution if a current of 2.50 A is applied to
the solution for 365 s? (red(Ni2+/Ni) = 0.257 V, F = 96485
C/mol)a)0.555 gb)1.11 gc)0.0713 gd)0.278 ge)1.08 gAns:d
Algorithm:Yes Chapter/Section:18.8 Difficulty:Moderate
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis132.What mass of chromium could
be deposited by electrolysis of an aqueous solution of Cr2(SO4)3
for 175 minutes using a constant current of 13.0 amperes?a)0.187
gb)220.7 gc)0.409 gd)36.8 ge)24.5 gAns:e Algorithm:Yes
Chapter/Section:18.8 Difficulty:Moderate Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:electrolyticcells
Keyword5:stoichiometryofelectrolysis133.Which of the following are
incorrectly paired?a)Alumina pure aluminum oxideb)Downs cell
electrolyzes molten sodium chloridec)Mercury cell used in
preventing contamination of NaOH by NaCld)Hall-Heroult process uses
cryolite in production of aluminume)All of these are correct.Ans:e
Algorithm:No Chapter/Section:18.9 Difficulty:Easy
Keyword1:Chemistry Keyword2:generalchemistry
Keyword3:electrochemistry Keyword4:electrolyticcells
Keyword5:commercialelectrolyticprocesses134.Which of the following
used to be more precious than gold or silver, due to difficulties
refining it?a)copperb)aluminumc)tind)zince)ironAns:b Algorithm:No
Chapter/Section:18.9 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:electrolyticcells
Keyword5:commercialelectrolyticprocesses135.What are the products
of the chlor-alkali process?a)sodium and sodium chlorideb)sodium
chloride and chlorinec)sodium and chlorined)sodium hydroxide and
chlorinee)aluminum and cryoliteAns:d Algorithm:No
Chapter/Section:18.9 Difficulty:Easy Keyword1:Chemistry
Keyword2:generalchemistry Keyword3:electrochemistry
Keyword4:electrolyticcells
Keyword5:commercialelectrolyticprocesses