1.what is the oxidation number of manganese in 11.what...
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A) +7 B) +2 C) +3 D) +4
1. What is the oxidation number of manganese in ?
A) P4O10 B) PCl5
C) Ca3(PO4)2 D) KH2PO3
2. In which substance does phosphorus have a +3 oxidationstate?
A) –1 B) –2 C) +3 D) +4
3. What is the oxidation number of nitrogen in HNO2?
A) Na2S B) CaSO4
C) S D) SO2
4. In which substance does sulfur have a negative oxidationnumber?
A) –2 B) +2 C) –4 D) +4
5. What is the oxidation number of Pt in K2PtCl6?
A) H3O+ B) OH– C) H2O D) H2O2
6. Oxygen has an oxidation number of –1 in
A) –1 B) +2 C) –3 D) +4
7. What is the oxidation state of nitrogen in the compoundNH4Br?
A) –2 B) +2 C) –4 D) +4
8. What is the oxidation number of carbon in NaHCO3?
A) NaClO B) NaClO2
C) NaClO3 D) NaClO4
9. In which compound does chlorine have the highestoxidation number?
A) 0 to +2 B) 0 to –2C) +2 to 0 D) –2 to 0
10. Given the reaction that occurs in an electrochemicalcell:
Zn(s) + CuSO4(aq) ZnSO4(aq) + Cu(s)
During this reaction, the oxidation number of Znchanges from
A) It loses electrons, and its oxidation numberdecreases.
B) It loses electrons, and its oxidation numberincreases.
C) It gains electrons, and its oxidation numberdecreases.
D) It gains electrons, and its oxidation numberincreases.
11. What occurs when a substance in anoxidation-reduction reaction is reduced?
A) Mn4+ B) O2– C) H+ D) Cl–
12. In the reaction
MnO2 + 4 HCl ® MnCl2 + 2 H2O + Cl2,
which species is reduced?
A) Fe(s) Fe2+(aq) + 2e–
B) Fe2+(aq) Fe(s) + 2e–
C) Fe(s) + 2e– Fe2+(aq)D) Fe2+(aq) + 2e– Fe(s)
13. Which half-reaction correctly represents oxidation?
A) The manganese is reduced and its oxidationnumber changes from +4 to +2.
B) The manganese is oxidized and its oxidationnumber changes from +4 to +2.
C) The manganese is reduced and its oxidationnumber changes from +2 to +4.
D) The manganese is oxidized and its oxidationnumber changes from +2 to +4.
14. What occurs during the reaction below?
4 HCl + MnO2 ® MnCl2 + 2 H2O + Cl2
A) 3Ag + 3e– ® 3Ag+ B) 3Ag ® 3Ag+ + 3e–
C) Au3+ + 3e– ® Au D) Au3+ ® Au + 3e–
15. Given the reaction:
3 Ag + Au3+ ® 3 Ag+ + Au
Which equation correctly represents the oxidationhalf-reaction?
A) transmutation B) reductionC) oxidation D) neutralization
16. During which process does an atom gain one or moreelectrons?
A) mass, onlyB) charge, onlyC) both mass and chargeD) neither mass nor charge
17. In a redox reaction, there is a conservation of
A) reduced and its oxidation number increasesB) reduced and its oxidation number decreasesC) oxidized and its oxidation number increasesD) oxidized and its oxidation number decreases
18. In the reaction
2 Al + 3 Ni(NO3)2 ® 2 Al(NO3)3 + 3 Ni,
the aluminum is
A) loss of protons B) gain of protonsC) loss of electrons D) gain of electrons
19. In an oxidation-reduction reaction, reduction is definedas the
A) Al3+ B) Cu2+ C) S6+ D) O2–
20. Which is reduced in the reaction below?
2 Al + 3 CuSO4 ® Al2(SO4)3 + 3 Cu
A) Reducing agents gain protons.B) Reducing agents gain electrons.C) Reducing agents are oxidized.D) Reducing agents are reduced.
21. What happens to reducing agents in chemical reactions?
A) Zn2+ B) Mg2+ C) Co2+ D) Ca2+
22. Which ion is most easily reduced?
A) reduced and is the oxidizing agentB) reduced and is the reducing agentC) oxidized and is the oxidizing agentD) oxidized and is the reducing agent
23. In the reaction
Cu0 + 2 H2SO4 ® CuSO4 + 2 H2O + SO2,
copper is
A) Sn2+ B) Cu2+ C) Al3+ D) Fe3+
24. Which ion can be both an oxidizing agent and reducingagent?
A) Fe(s) B) Fe2+(aq)C) Zn(s) D) Zn2+(aq)
25. Given the redox reaction:
Fe2+(aq) + Zn(s) ® Zn2+(aq) + Fe(s)
Which species acts as a reducing agent?
A) loses protonsB) gains protonsC) acts as an oxidizing agentD) acts as a reducing agent
26. When a substance is oxidized, it
A) Ag+ B) Ag C) Pb D) Pb2+
27. In the reaction
Pb + 2 Ag+ ® Pb2+ + 2 Ag,
the oxidizing agent is
A) Zn(s) ® Zn2+ + 2e–
B) 2 H + 2e– ® H2(g)C) Zn2+ + 2e ® Zn(s)D) 2 Cl– ® Cl2(g) + 2e–
28. Given the reaction:
Zn(s) + 2 HCl(aq) ® ZnCl2(aq) + H2(g)
Which equation represents the correct oxidationhalf-reaction?
A) Al + 3e– Al3+ B) Al Al3+ + 3e–
C) O2+ 4e– 2 O2– D) O2 2 O2– + 4e–
29. Given the reaction for the corrosion of aluminum:
4 Al + 3 O2 2 Al2O3Which half-reaction correctly represents the oxidationthat occurs?
A) Fe2+ ®Fe3+ + e– B) Fe2+ + 2e– ® FeC) Fe3+ + e– ® Fe2+ D) Fe ® Fe2+ + 2e–
30. Which half-reaction equation represents the reductionof an iron(II) ion?
A) 6 B) 2 C) 3 D) 8
31. Given the reaction:
2 Al0(s) + 3 Ni2+ (aq) ® 2 Al3+(aq) + 3 Ni0(s)
What is the total number of moles of electronslost by 2 moles of Al0(s)?
A) 2 Na+ + S2– ® Na2SB) H+ + C2H3O2– ® HC2H3O2
C) NH3 + H+ + Cl– ® NH4+ + ClD) Cu + 2 Ag+ + 2 NO3– ® 2 Ag + Cu2+ + 2
NO3–
32. Which equation represents a redox reaction?
A) 2 KBr + F2 ® 2 KF + Br2
B) 2 HCl + Mg(OH)2 ® 2 HOH + MgCl2
C) 2 NaCl + H2SO4 ® Na2SO4 + 2 HClD) Ca(OH)2 + Pb(NO3)2 ® Ca(NO3)2 + Pb(OH)2
33. Which is a redox reaction?
A) reduction, onlyB) oxidation, onlyC) both oxidation and reductionD) neither oxidation nor reduction
34. The reaction
CuO + CO ® CO2 + Cu
is an example of
A) –2 to –3 B) –2 to +3C) –3 to –2 D) –3 to +2
35. In the reaction
4 NH3 + 5 O2 ® 4 NO + 6 H2O,
the oxidation number of nitrogen changes from
A) HCl + KOH ® KCl + H2OB) 4 HCl + MnO2 ® MnCl2 + 2 H2O + Cl2
C) 2 HCl +CaCO3 ® CaCl2 + H2O + CO2
D) 2 HCl + FeS ® FeCl2 + H2S
36. Which is a redox reaction?
A) Au B) Ag C) Cr D) Cu
37. According to Reference Table J, which metal will reactspontaneously with H+?
A) Ca2+ B) Cr3+ C) Cu+ D) Ag+
38. According to Reference Table J, which of these ions ismost easily reduced?
A) Cl2(g) + 2NaBr(aq) Br2( ) + 2NaCl(aq)B) Cl2(g) + 2NaF(aq) F2(g) + 2NaCl(aq)C) I2(s) + 2NaBr(aq) Br2( ) + 2NaI(aq)D) I2(s) + 2NaF(aq) F2(g) + 2NaI(aq)
39. Which reaction occurs spontaneously?
A) Cl2 + 2e– ® 2 Cl B) Cl2 ® Cl– + 2e–
C) 2 Br– + 2e– ® Br2 D) Br– ® Br2 + 2e–
40. Which half-reaction shows both the conservation ofmass and the conservation of charge?
A) Al3+ + 3e– ® Al B) Al3+ + 3e– ® 3 AlC) Al3+ ® Al + 3e– D) Al3+ ® 3 Al + 3e–
41. Which half-reaction for the reduction of Al3+ to Al iscorrectly balanced?
A) temperature B) volumeC) matter D) nothing
42. A chemical reaction always demonstrates theconservation of what?
A) 1 B) 2 C) 0.5 D) 4
43. In the reaction
Ni + 2 Ag+ ® Ni2+ + 2 Ag,
what is the total number of moles of electrons lost by 1mole of Ni?
A) Cu + e– ® Cu+ B) Cu2+ + 2e– ® CuC) Cu+ ® Cu + e– D) Cu2+ ® Cu + 2e–
44. Which half-reaction shows conservation of charge?
A) nickel B) zincC) chromium D) iron
45. Which metal will undergo the greatest degree ofcorrosion if left unprotected from its surroundings?
A) are reducedB) are oxidizing agentsC) form oxides that are self-protectiveD) form oxides
46. Iron corrodes more easily than aluminum and zincbecause aluminum and zinc both
A) Al and Fe B) Al and ZnC) Fe and Na D) Fe and Zn
47. Which two metals resist corrosion by formingself-protective coatings?
A) 10 B) 7 C) 5 D) 4
48. Given the reaction:
When the equation is correctly balanced using smallestwhole numbers, the sum of the coefficients will be
A) 1 B) 2 C) 3 D) 4
49. When the equation
is correctly balanced using the smallest whole numbercoefficients, the coefficient of the Pb2+ will be
A) 1 B) 2 C) 3 D) 4
50. When the equation
is completely balanced, the coefficient of Al will be
51. Base your answer to the following question on the reaction below
A) 1 B) 2 C) 3 D) 6
If 3 moles of Cu react according to the equation above,the total number of moles of electrons transferred willbe
52. Base your answer to the following question on theequation and diagram below represent anelectrochemical cell at 298 K and 1 atmosphere.
A) Mg(s) B) Mg2+ (aq)C) Ag(s) D) Ag+(aq)
Which species is oxidized when the switch is closed?
A) a positive and negative electrodeB) an anode and a cathodeC) a redox reaction that produces an electric
currentD) an electric current that causes a redox reaction
53. A chemical cell differs from an electrolytic cell becausein a chemical cell there is
A) only oxidation occursB) only reduction occursC) both oxidation and reduction occurD) neither oxidation nor reduction occurs
54. In a chemical cell, electrical energy will be producedwhen
A) The concentration of decreases and the number of moles of increases.B) The concentration of decreases and the number of moles of increases.C) The concentration of increases and the number of moles of decreases.D) The concentration of increases and the number of moles of decreases.
55. Given the equation for the overall reaction in a lead-acid storage battery:
Which occurs during the charging of the battery?
A) Ni3+ B) Ni2+ C) Cd D) Cd2+
56. Given the reaction for the nickel-cadmium battery:
2 NiO(OH)3 + Cd + 2 H2O ® 2 Ni(OH)2 + Cd(OH)2Which species is oxidized during the discharge of thebattery?
57. Base your answer to the following question on thediagram of the chemical cell at 298 K and on theequation below.
A) gain electrons B) lose electronsC) gain protons D) lose protons
In the given reaction, the Ag+ ions
A) an oxidation reaction, onlyB) a reduction reaction, onlyC) both an oxidation reaction and a reduction
reactionD) neither an oxidation reaction nor a reduction
reaction
58. The electricity produced by a battery results from
59. Base your answer to the following question on thediagram below which represents a chemical cell at 298K and 1 atmosphere.
A) Zn to Zn2+ B) Zn to CuC) Cu to Zn2+ D) Cu to Zn
When switch S is closed, electrons in the externalcircuit will flow from
A) at the cathode in both an electrolytic cell and avoltaic cell
B) at the cathode in an electrolytic cell and at theanode in a voltaic cell
C) at the anode in both an electrolytic cell and avoltaic cell
D) at the anode in an electrolytic cell and at thecathode in a voltaic cell
60. Where does oxidation occur in an electrochemical cell?
A) Positive ions migrate toward the anode, wherethey lose electrons.
B) Positive ions migrate toward the anode, wherethey gain electrons.
C) Positive ions migrate toward the cathode, wherethey lose electrons.
D) Positive ions migrate toward the cathode,where they gain electrons.
61. The diagram below shows the electrolysis of fused KCl.
What occurs when the switch is closed?
62. Base your answer to the following question on thediagram of the chemical cell shown below. The reactionoccurs at 1 atmosphere and 298 K.
A) Pb is oxidized and electrons flow to the Znelectrode.
B) Pb is reduced and electrons flow to the Znelectrode.
C) Zn is oxidized and electrons flow to the Pbelectrode.
D) Zn is reduced and electrons flow to the Pbelectrode.
When the switch is closed, what occurs?
A) Both occur at the anode.B) Both occur at the cathode.C) Oxidation occurs at the anode and reduction
occurs at the cathode.D) Oxidation occurs at the cathode and reduction
occurs at the anode.
63. Which statement is true about oxidation and reductionin an electrochemical cell?
A) +0.52 V B) +0.34 VC) –0.52 V D) –0.34 V
64. Based on Reference Table X, what is the standardelectrode potential (E 0) for the oxidation of Cu(s) to Cu2+(aq)?
A) 0.00 V B) 0.34 VC) 0.42 V D) 0.76 V
65. What is the potential (Eo) of a zinc-copper chemicalcell at equilibrium?
A) 0.26 V B) 0.50 VC) 0.76 V D) 1.021 V
66. Given the reaction:
Zn(s) + Ni2+ + (aq) ® Zn2+(aq) + Ni(s)
What is the cell voltage (E0) for the overall reaction?
A) 3.90 V B) 2.30 VC) 0.90 V D) 0.70 V
67. Given the reaction:
3 Ag(s) + Au3+(aq) ® 3 Ag+(aq) + Au(s)
The net potential (E0) for the overall reaction is
A) a redox reaction occursB) a spontaneous reaction occursC) an electric current is producedD) an electric current causes a chemical reaction
68. An electrolytic cell is different from an electrochemicalcell because in an electrolytic cell
A) anode, at which oxidation occursB) anode, at which reduction occursC) cathode, at which oxidation occursD) cathode, at which reduction occurs
69. In an electrolytic cell, the negative electrode is calledthe
A) anode, which is negatively chargedB) anode, which is positively chargedC) cathode, which is negatively chargedD) cathode, which is positively charged
70. In an electrolytic cell, a negative ion will migrate to andundergo oxidation at the
A) It produces electrical energy.B) It requires an external energy source.C) It uses radioactive nuclides.D) It undergoes a spontaneous redox reaction.
71. Which statement describes one characteristic of anoperating electrolytic cell?
72. Base your answer to the following question on thediagram below of an electrolytic cell in which theelectrodes are tin and copper.
A) anode and is positiveB) anode and is negativeC) cathode and is positiveD) cathode and is negative
In this electrolytic cell, electrode A is designated as the
A) an electrolytic cell in which an exothermicreaction occurs
B) an electrolytic cell in which an endothermicreaction occurs
C) a chemical cell in which an exothermic reactionoccurs
D) a chemical cell in which an endothermic reactionoccurs
73. Given the cell reaction:
2 H2O( ) + electricity ® 2 H2(g) + O2(g)
This cell is best described as
A) 2 H2O( ) ® 2 H2(g) + O2(g)B) 2 HgO(s) ® 2 Hg( ) + O2(g)C) 2 KClO3( ) ® 2 KCl(s) + 3 O2(g)D) MgCO3(s) ® MgO(s) + CO2(s)
74. Which net reaction occurs by the process ofelectrolysis?
A) Cl– B) C0 C) Ca0 D) Ca2+
75. In the electrolysis of molten CaCl2, the particle reducedis
A) Ka and Ca B) Ka and CrC) Cu and Zn D) Cu and Hg
76. Which metals are obtained by electrolysis of their fusedsalts?
A) lithium B) goldC) silver D) zinc
77. Which element is obtained only by the electrolysis ofits fused salt?
A) Sr and Cr B) Be and FeC) Li and Ni D) Na and Ca
78. Which metals are produced commercially only byelectrolysis of their fused salts?