Introductory Chemistry: Atoms First, 5e (Russo/Silver)
Chapter 10 Electron Transfer in Chemical Reactions
10.1 Multiple-Choice Questions
1) What is electricity?
A) flow of atoms
B) flow of protons
C) flow of neutrons
D) flow of electrons
2) Which of the following does not have the same number of electrons when compared with the
rest?
A) Mg2+
B) O2-
C) F
D) Ne
3) Which of the following has 8 electrons in the outer shell?
A) Ca2+
B) Cl+
C) S2+
D) Fe3+
4) In which case is chlorine in its highest oxidation state?
A) sodium hypochlorite
B) sodium chloride
C) sodium perchlorate
D) sodium chlorate
5) What is the oxidation state of manganese in the compound KMnO4?
A) +4
B) +2
C) +7
D) -4
6) What is the oxidation state of chromium in the compound K2Cr2O7?
A) +4
B) +6
C) +7
D) -1
7) Which atom in the compound K2C2O4 has a positive oxidation state?
A) potassium
B) carbon
C) both potassium and carbon
D) both potassium and oxygen
8) Which atom in the compound KClO3 has a negative oxidation state?
A) potassium
B) oxygen
C) both potassium and chlorine
D) both chlorine and oxygen
9) What is the oxidation state of the nitrogen atom in the compound NCl3?
A) 0
B) +3
C) +5
D) -3
10) What is the oxidation state of the carbon atom in the compound CO2?
A) +2
B) +3
C) +4
D) -2
11) Which atom(s) has a more positive oxidation state on the product side than the reactant side?
Fe2O3 + 3CO → 2Fe + 3CO2
A) iron
B) oxygen
C) carbon
D) carbon and iron
12) Which atom(s) has a more negative oxidation state on the product side than the reactant side?
Fe2O3 + 3CO → 2Fe + 3CO2
A) iron
B) oxygen
C) carbon
D) carbon and oxygen
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13) In a chemical bond, which atom gets ownership the shared electrons?
A) the larger element
B) the smaller element
C) the more electronegative element
D) the most electropositive element
14) In the water molecule, which atom holds the shared electrons between hydrogen and
oxygen?
A) oxygen
B) hydrogen
C) both are shared equally
D) One cannot say unless the state of water is known.
15) Which of the following elements may have more than one oxidation number?
A) hydrogen
B) sodium
C) calcium
D) lithium
16) Which of the following elements may have an oxidation number of +1 or -1?
A) hydrogen
B) sodium
C) potassium
D) lithium
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17) Which of the following elements may have an oxidation number other than +2?
A) magnesium
B) calcium
C) barium
D) iron
18) Which of the following elements may not have an oxidation number of -1?
A) chlorine
B) hydrogen
C) sodium
D) fluorine
19) Which of the following elements may have +4 charge?
A) magnesium
B) aluminum
C) carbon
D) chlorine
20) Which of the following elements may have a +3 charge when it becomes an ion?
A) magnesium
B) aluminum
C) carbon
D) chlorine
21) In which of the following is oxygen not at the -2 oxidation state?
A) water
B) methanol
C) hydrogen peroxide
D) carbon dioxide
22) The only element that is more electronegative than oxygen is ________.
A) chlorine
B) fluorine
C) nitrogen
D) sulfur
23) The overall charge of sodium dichromate is ________.
A) 0
B) +1
C) +2
D) -2
24) What is the sum of the oxidation states in the following species H2SbO3–?
A) 0
B) -1
C) +2
D) -2
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25) The oxidation state of nitrogen in the ammonium ion is ________.
A) +3
B) +1
C) -3
D) -1
26) The oxidation state of sulfur in the sulfate ion is ________.
A) +6
B) +7
C) -2
D) +4
27) The oxidation state of chlorine in the perchlorate ion is ________.
A) +8
B) +7
C) -1
D) +6
28) Identify the compound that contains bromine with a +3 oxidation state.
A) NaBrO2
B) NaBrO3
C) NaBrO
D) NaBrO4
29) Halogens most often have an oxidation state of ________.
A) +1
B) -1
C) +7
D) -3
30) The oxidation state of chlorine in sodium perchlorate is ________.
A) -1
B) +1
C) +3
D) +7
31) Which of the following is true for the following reaction?
Mg + O2 → 2 MgO
A) Magnesium is oxidized.
B) The oxidation state of magnesium in MgO is +2.
C) Oxygen is reduced.
D) All of the above are true.
32) Which of the following is true for the following reaction?
Cu + ZnCl2 → CuCl2 + Zn
A) Cu is oxidized.
B) Cu is a reducing agent.
C) Zn+2 is reduced.
D) All of the above statements are correct.
33) Which of the following is true for the following reaction?
Zn + CuCl2 → ZnCl2 + Cu
A) The solution will turn blue.
B) The solution will turn from blue to light blue.
C) The gray zinc powder will disappear.
D) Both B and C are correct.
34) The oxidation state of phosphorus in P4 is ________.
A) +4
B) +3
C) -3
D) 0
35) The oxidation state of oxygen gas is ________.
A) -4
B) +2
C) -2
D) 0
36) What is reduction?
A) loss of electrons
B) increase in oxidation number
C) gain of electrons
D) two of the above
37) What is oxidation?
A) loss of electrons
B) increase in oxidation number
C) gain of electrons
D) two of the above
38) The oxidizing agent is ________.
A) reduced in a redox equation
B) oxidized in a redox equation
C) reduced in an oxidation reaction
D) oxidized in a reduction reaction
39) The reducing agent is ________.
A) reduced in a redox equation
B) oxidized in a redox equation
C) reduced in an oxidation reaction
D) oxidized in a reduction reaction
40) Identify the reducing agent in the following chemical process (a lead storage battery).
Pb + PbO2 + 2H+ + 2HSO4– → 2PbSO4 + 2H2O
A) PbO2
B) Pb
C) H+
D) 2HSO4–
41) Identify the reduced species in the following chemical process (a lead storage battery).
Pb + PbO2 + 2H+ + 2HSO4– → 2PbSO4 + 2H2O.
A) PbO2
B) Pb
C) H+
D) 2HSO4–
42) Identify the oxidizing agent in the following chemical process.
Fe + Cu(NO3)2 → Fe(NO3)2 + Cu
A) Fe
B) Cu+2
C) NO3–
D) Cu
43) Identify the oxidized species in the following chemical process.
Fe + Cu(NO3)2 → Fe(NO3)2 + Cu
A) Fe
B) Cu+2
C) NO3–
D) Cu
44) Identify the reducing agent in the following chemical process.
Cu + 2AgCl → CuC12 + 2Ag
A) Ag
B) Ag+
C) Cl-
D) Cu
45) Identify the reduced species in the following chemical process.
Cu + 2AgCl → CuC12 + 2Ag
A) Ag
B) Ag+
C) Cl-
D) Cu
46) Identify the equation that has the greatest number of electrons transferred.
A) NaClO → NaClO2
B) 2 Mg + O2 → 2 MgO
C) CuCl → CuCl2
D) NaClO2 → NaClO4
47) Identify the equation that has the least number of electrons transferred
A) NaClO → NaClO2
B) 2 Mg + O2 → 2 MgO
C) CuCl → CuCl2
D) NaClO2 → NaClO4
48) Identify the element that was oxidized.
H2O + CO2 → H2CO3
A) carbon
B) oxygen
C) hydrogen
D) None of the elements were oxidized.
49) Identify the element that was reduced.
H2SO4 + Al(OH)3 → Al2(SO4)3 + H2O
A) aluminum
B) sulfur
C) oxygen
D) No elements were either oxidized or reduced.
50) Identify the element that was oxidized.
3 P + 5 HNO3 + 2 H2O → 5 NO + 3 H3PO4
A) phosphorus
B) nitrogen
C) oxygen
D) No elements were either oxidized or reduced.
51) Identify the oxidizing agent.
I2 + 6 H2O + 5 Cl2 → 2HIO3 + 10 HCl
A) I2
B) H2O
C) Cl2
D) the oxygen in water
52) Identify the oxidation-reduction equation.
A) NaOH + HCl → NaCl + H2O
B) AgNO3 + NaCl → AgCl + NaNO3
C) CH4 + 2 O2 → CO2 + 2 H2O
D) CaO + CO2 → CaCO3
53) A fuel cell is essentially a battery which uses the following reaction to produce electricity.
What is happening at the cathode of such a fuel cell?
2H2 + O2 → 2H2O
A) Hydrogen is being oxidized.
B) Oxygen is being oxidized.
C) Nothing at all is happening there.
D) Oxygen is being reduced.
54) What chemical process is happening at the anode of a fuel cell, which uses the following
reaction to generate electricity?
2H2 + O2 → 2H2O
A) Hydrogen is being oxidized.
B) Oxygen is being oxidized.
C) Nothing at all is happening there.
D) Oxygen is being reduced.
55) The reactants in a dry cell are ________.
A) Cu+2 and Zn
B) Zn+2 and Cu
C) Zn and MnO2
D) Zn+2 and Al
56) The following reaction is an example of a ________ battery.
Zn + Cu+2 → Zn+2 + Cu
A) zinc-copper
B) copper-zinc
C) copper-silver
D) copper-zinc—hydrogen
57) Consult the EMF activity series and predict which of the following changes will occur if an
iron nail is placed in an aqueous solution containing the (Sn2+) ion.
A) Nothing at all will happen (no reaction).
B) Tin will be further oxidized.
C) Iron will be reduced.
D) Iron will be oxidized.
58) Consult the EMF activity series and predict which of the following changes will occur if an
24K gold ring (pure gold) is placed in an aqueous solution containing hydrochloric acid.
A) Nothing at all will happen (no reaction).
B) Hydrogen will be further oxidized.
C) Gold will be reduced.
D) Gold will be oxidized.
59) Which of the following is the most easily reduced?
A) Mn2+
B) Fe2+
C) Zn2+
D) Cu2+
60) Which of the following is the most easily reduced?
A) K+
B) Na+
C) Au+
D) Hg2+