Question 1

Which of the following pairs of ions cannot coexist in solution because a spontaneous redox reaction occurs?

Accepted Answer

A)  Cu2+ and Zn2+ 
B)  Fe3+ and Hg22+ 
C)  Cu2+ and I- 
D)  Al3+ and S2- 
E)  All of these pairs of ions can coexist. 
A)  Cu2+ and Zn2+ 
B)  Fe3+ and Hg22+ 
C)  Cu2+ and I- 
D)  Al3+ and S2- 
E)  All of these pairs of ions can coexist. B

Question 2

‪   
Determining Oxidation Numbers
-Determine the oxidation number of the bold face carbon atom in pyruvic acid:

Accepted Answer

A) -2 
B)  +2 
C)  +3 
D)  +4 
E)  none of these 
A) -2 
B)  +2 
C)  +3 
D)  +4 
E)  none of these B

Question 3

‪   
Determining Oxidation Numbers
-Determine the oxidation state of the carbon atom in bold print:
CH3CH2F

Accepted Answer

A)  0 
B)  +1 
C)  +2 
D)  +3 
E) -1 
A)  0 
B)  +1 
C)  +2 
D)  +3 
E) -1 E

Question 4

Cobalt(III) oxide reacts with hydrogen gas to form cobalt metal and water.
Co2O3(s) + 3 H2(g)  $\rightarrow$ 2 Co(s) + 3 H2O(g)
What does this tell you about the relative strength of the oxidizing and reducing agents in this reaction?

Accepted Answer

A)  The Co3+ ion is a stronger reducing agent than cobalt metal. 
B)  Cobalt metal is a better reducing agent than water. 
C)  Cobalt metal is a weaker reducing agent than hydrogen. 
D)  The Co3+ ion is a weaker oxidizing agent than water. 
E)  Statements (a) through (d) above are all false. 
A)  The Co3+ ion is a stronger reducing agent than cobalt metal. 
B)  Cobalt metal is a better reducing agent than water. 
C)  Cobalt metal is a weaker reducing agent than hydrogen. 
D)  The Co3+ ion is a weaker oxidizing agent than water. 
E)  Statements (a) through (d) above are all false.

Question 5

Which of the following isn't an example of an oxidation-reduction reaction?

Accepted Answer

A)  Ca3P2(s) + 6 H2O(l) $\rightarrow$ 3 Ca2+(aq) + 6 OH-(aq) + 2 PH3(g) 
B)  2 PH3(g) + 4 O2(g)  $\rightarrow$ H3PO4(s) 
C)  P4(s) + 5 O2(g)  $\rightarrow$ P4O10(s) 
D)  6 Ca(s) + P4(s)  $\rightarrow$  2 Ca3P2(s) 
E)  All of the above are oxidation-reduction reactions. 
A)  Ca3P2(s) + 6 H2O(l) $\rightarrow$ 3 Ca2+(aq) + 6 OH-(aq) + 2 PH3(g) 
B)  2 PH3(g) + 4 O2(g)  $\rightarrow$ H3PO4(s) 
C)  P4(s) + 5 O2(g)  $\rightarrow$ P4O10(s) 
D)  6 Ca(s) + P4(s)  $\rightarrow$  2 Ca3P2(s) 
E)  All of the above are oxidation-reduction reactions.

Question 6

An electric current is passed through a solution of CuSO4(aq) producing Cu(s) at the cathode and O2(g) at the anode. If 3.48 L of O2(g) measured at STP is produced at the anode, how many grams of Cu(s) must have been deposited on the cathode?

Accepted Answer

A)  3.48 g 
B)  4.93 g 
C)  9.87 g 
D)  19.7 g 
E)  none of these 
A)  3.48 g 
B)  4.93 g 
C)  9.87 g 
D)  19.7 g 
E)  none of these

Question 7

Calculate the complex dissociation equilibrium constant (Kd) for the Cd(NH3)42+ complex from the following data at 298K.

Accepted Answer

A)  2.7 x 10-7 
B)  0.19 
C)  6.6 
D)  3.6 x 106 
E)  none of the above 
A)  2.7 x 10-7 
B)  0.19 
C)  6.6 
D)  3.6 x 106 
E)  none of the above

Question 8

A molten sample of TiCl4 was electrolyzed for 10.0 hours at 12 amps. What is the ratio of the weight of Cl2 produced compared to that of Ti?

Accepted Answer

A)  0.34 g Cl2/1.00 g Ti 
B)  0.68 g Cl2/1.00 g Ti 
C)  0.74 g Cl2/1.00 g Ti 
D)  1.48 g Cl2/1.00 g Ti 
E)  2.96 g Cl2/1.00 g Ti 
A)  0.34 g Cl2/1.00 g Ti 
B)  0.68 g Cl2/1.00 g Ti 
C)  0.74 g Cl2/1.00 g Ti 
D)  1.48 g Cl2/1.00 g Ti 
E)  2.96 g Cl2/1.00 g Ti

Question 9

Which of the following is the correct half-cell reaction for the anode process in the electrolysis of an aqueous solution of potassium sulfate?

Accepted Answer

A)  SO42-(aq)  $\rightarrow$ SO2(g) + O2(g) + 2 e- 
B)  H2O(l)  $\rightarrow$ 1/2 O2(g) + 2 H+(aq) + 2 e- 
C)  H2O(l) + 1/2 O2(g) + 2 e-  $\rightarrow$  2 OH-(aq) 
D)  SO42-(aq) + 4 H+(aq) + 2 e-  $\rightarrow$ SO2(g) + 2 H2O(l) 
E)  3 H2O(l) + e-  $\rightarrow$  1/2 H2(g) + 3 OH-(aq) + 2 H+(aq) 
A)  SO42-(aq)  $\rightarrow$ SO2(g) + O2(g) + 2 e- 
B)  H2O(l)  $\rightarrow$ 1/2 O2(g) + 2 H+(aq) + 2 e- 
C)  H2O(l) + 1/2 O2(g) + 2 e-  $\rightarrow$  2 OH-(aq) 
D)  SO42-(aq) + 4 H+(aq) + 2 e-  $\rightarrow$ SO2(g) + 2 H2O(l) 
E)  3 H2O(l) + e-  $\rightarrow$  1/2 H2(g) + 3 OH-(aq) + 2 H+(aq)

Question 10

Use a table of standard reduction potentials to determine which of the following statements is true for the electrochemical cell diagrammed below.

Accepted Answer

A)  The Al is the cathode. 
B)  Electrons move from the Al electrode to the Fe electrode. 
C)  The mass of the Al electrode decreases. 
D)  Both (b) and (c) are true. . 
E)  Both (a) and (c) are true 
A)  The Al is the cathode. 
B)  Electrons move from the Al electrode to the Fe electrode. 
C)  The mass of the Al electrode decreases. 
D)  Both (b) and (c) are true. . 
E)  Both (a) and (c) are true

Question 11

Use the following half reactions and accompanying standard reduction potentials to determine the best reducing agent.

Accepted Answer

A)  Ga3+ 
B)  Be2+ 
C)  Be 
D)  Pd2+ 
E)  Pd 
A)  Ga3+ 
B)  Be2+ 
C)  Be 
D)  Pd2+ 
E)  Pd

Question 12

What is the ratio by weight of Br2 to Cr if a molten sample of CrBr2 is electrolyzed for 4.00 hr. at 10.0 amps?

Accepted Answer

A)  1.05 g Br2/1 g Cr 
B)  1.54 g Br2/1 g Cr 
C)  2.05 g Br2/1 g Cr 
D)  3.07 g Br2/1 g Cr 
E)  4.61 g Br2/1 g Cr 
A)  1.05 g Br2/1 g Cr 
B)  1.54 g Br2/1 g Cr 
C)  2.05 g Br2/1 g Cr 
D)  3.07 g Br2/1 g Cr 
E)  4.61 g Br2/1 g Cr

Question 13

Calculate the weight of sodium metal that would be produced by the electrolysis of molten sodium chloride for 1.00 hour with a 10.0-amp current.

Accepted Answer

The answer of Calculate the weight of sodium metal that...

Question 14

Calculate the amount of aluminum produced in 1.00 hour by the electrolysis of molten AlCl3 if the current is 10.0 A.

Accepted Answer

Question 15

Which of the following electrolysis processes will produce the largest volume of Cl2 gas at STP?

Accepted Answer

A)  passing 35 amps for 20 hours through an aqueous Na2SO4 solution 
B)  passing 10 amps for 2.69 hours through a 1 M NaCl solution 
C)  passing 2 moles electrons through a 1 M CaCl2 solution 
D)  passing 1.5 moles electrons through a 5 M CaCl2 solution 
E)  passing 1.4 moles electrons through a 5 M AlCl3 solution 
A)  passing 35 amps for 20 hours through an aqueous Na2SO4 solution 
B)  passing 10 amps for 2.69 hours through a 1 M NaCl solution 
C)  passing 2 moles electrons through a 1 M CaCl2 solution 
D)  passing 1.5 moles electrons through a 5 M CaCl2 solution 
E)  passing 1.4 moles electrons through a 5 M AlCl3 solution

Question 16

What is the oxidation state of the osmium atom in an unknown salt if 26.7 grams of osmium plate out when a current of 15.0 amps is passed through a solution of this salt for 1.00 hour?

Accepted Answer

A)  Os+ 
B)  Os2+ 
C)  Os3+ 
D)  Os4+ 
E)  Os5+ 
A)  Os+ 
B)  Os2+ 
C)  Os3+ 
D)  Os4+ 
E)  Os5+

Question 17

What is the magnitude of the standard-state cell potential for the following redox reaction?
2 Al(s) + 3 Pb2+(aq)  $\rightarrow$  2 Al3+(aq) + 3 Pb(s)

Accepted Answer

A)  1.58 V 
B)  1.83 V 
C)  3.03 V 
D)  3.790 V 
E)  4.866 V 
A)  1.58 V 
B)  1.83 V 
C)  3.03 V 
D)  3.790 V 
E)  4.866 V

Question 18

Use a table of standard reduction potentials to determine which is the strongest oxidizing agent among the following.

Accepted Answer

A)  Cl2 gas at 1 atm pressure 
B)  O2 gas at 1 atm pressure in contact with 1 M acid 
C)  F2 gas at 1 atm pressure 
D)  Ag metal 
E)  H2O2 in acid solution 
A)  Cl2 gas at 1 atm pressure 
B)  O2 gas at 1 atm pressure in contact with 1 M acid 
C)  F2 gas at 1 atm pressure 
D)  Ag metal 
E)  H2O2 in acid solution

Question 19

refer to the following reaction which occurs in basic solution.
CrOS1U1B14S1U1B0S1U1P12-S1S1P0 + PHS1U1B13S1U1B0 $\rightarrow$Cr(OH)S1U1B14S1U1B0S1U1P1-S1S1P0 + PS1U1B14S1U1B0
-How many CrO42- ions are consumed in the balanced chemical equation?

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  6 
A)  1 
B)  2 
C)  3 
D)  4 
E)  6

Question 20

Write a balanced chemical equation for the following reaction, which can be used to standardize aqueous permanganate ion solutions.
H2C2O4(aq) + MnO4-(aq) + H+(aq) $\rightarrow$ CO2(g) + Mn2+(aq)

Accepted Answer

5 H₂C₂O<

Which of the following pairs of ions cannot coexist in solution because a spontaneous redox reaction occurs?

‪ Determining Oxidation Numbers -Determine the oxidation number of the bold face carbon atom in pyruvic acid:

‪ Determining Oxidation Numbers -Determine the oxidation state of the carbon atom in bold print: CH₃CH₂F

Cobalt(III) oxide reacts with hydrogen gas to form cobalt metal and water. Co₂O₃(s) + 3 H₂(g) $\rightarrow$ 2 Co(s) + 3 H₂O(g) What does this tell you about the relative strength of the oxidizing and reducing agents in this reaction?

Which of the following isn't an example of an oxidation-reduction reaction?

An electric current is passed through a solution of CuSO₄(aq) producing Cu(s) at the cathode and O₂(g) at the anode. If 3.48 L of O₂(g) measured at STP is produced at the anode, how many grams of Cu(s) must have been deposited on the cathode?

Calculate the complex dissociation equilibrium constant (K_d) for the Cd(NH₃)₄²⁺ complex from the following data at 298K.

A molten sample of TiCl₄ was electrolyzed for 10.0 hours at 12 amps. What is the ratio of the weight of Cl₂ produced compared to that of Ti?

Which of the following is the correct half-cell reaction for the anode process in the electrolysis of an aqueous solution of potassium sulfate?

Use a table of standard reduction potentials to determine which of the following statements is true for the electrochemical cell diagrammed below.

Use the following half reactions and accompanying standard reduction potentials to determine the best reducing agent.

What is the ratio by weight of Br₂ to Cr if a molten sample of CrBr₂ is electrolyzed for 4.00 hr. at 10.0 amps?

Calculate the weight of sodium metal that would be produced by the electrolysis of molten sodium chloride for 1.00 hour with a 10.0-amp current.

Calculate the amount of aluminum produced in 1.00 hour by the electrolysis of molten AlCl₃ if the current is 10.0 A.

Which of the following electrolysis processes will produce the largest volume of Cl₂ gas at STP?

What is the oxidation state of the osmium atom in an unknown salt if 26.7 grams of osmium plate out when a current of 15.0 amps is passed through a solution of this salt for 1.00 hour?

What is the magnitude of the standard-state cell potential for the following redox reaction? 2 Al(s) + 3 Pb²⁺(aq) $\rightarrow$ 2 Al³⁺(aq) + 3 Pb(s)

Use a table of standard reduction potentials to determine which is the strongest oxidizing agent among the following.

refer to the following reaction which occurs in basic solution. CrO₄^2- + PH₃ $\rightarrow$ Cr(OH)₄^- + P₄ -How many CrO₄^2- ions are consumed in the balanced chemical equation?

Write a balanced chemical equation for the following reaction, which can be used to standardize aqueous permanganate ion solutions. H₂C₂O₄(aq) + MnO₄^-(aq) + H⁺(aq) $\rightarrow$ CO₂(g) + Mn²⁺(aq)

Elements Compounds

The Mole

Structure of the Atom

The Covalent Bond

Ionic and Metallic Bonds

Gases

Making and Breaking of Bonds

Liquids and Solutions

Solids

An Introduction to Kinetics and Equilibrium

Acids and Bases

Chemical Thermodynamics

Kinetics

Nuclear Chemistry

Organic Chemistry

Filters

Exam 12: Oxidation-Reduction Reactions

Which of the following pairs of ions cannot coexist in solution because a spontaneous redox reaction occurs?

‪ Determining Oxidation Numbers -Determine the oxidation number of the bold face carbon atom in pyruvic acid:

‪ Determining Oxidation Numbers -Determine the oxidation state of the carbon atom in bold print: CH3CH2F

Cobalt(III) oxide reacts with hydrogen gas to form cobalt metal and water. Co2O3(s) + 3 H2(g) →\rightarrow→ 2 Co(s) + 3 H2O(g) What does this tell you about the relative strength of the oxidizing and reducing agents in this reaction?

Which of the following isn't an example of an oxidation-reduction reaction?

An electric current is passed through a solution of CuSO4(aq) producing Cu(s) at the cathode and O2(g) at the anode. If 3.48 L of O2(g) measured at STP is produced at the anode, how many grams of Cu(s) must have been deposited on the cathode?

Calculate the complex dissociation equilibrium constant (Kd) for the Cd(NH3)42+ complex from the following data at 298K.

A molten sample of TiCl4 was electrolyzed for 10.0 hours at 12 amps. What is the ratio of the weight of Cl2 produced compared to that of Ti?

Which of the following is the correct half-cell reaction for the anode process in the electrolysis of an aqueous solution of potassium sulfate?

Use a table of standard reduction potentials to determine which of the following statements is true for the electrochemical cell diagrammed below.

Use the following half reactions and accompanying standard reduction potentials to determine the best reducing agent.

What is the ratio by weight of Br2 to Cr if a molten sample of CrBr2 is electrolyzed for 4.00 hr. at 10.0 amps?

Calculate the weight of sodium metal that would be produced by the electrolysis of molten sodium chloride for 1.00 hour with a 10.0-amp current.

Calculate the amount of aluminum produced in 1.00 hour by the electrolysis of molten AlCl3 if the current is 10.0 A.

Which of the following electrolysis processes will produce the largest volume of Cl2 gas at STP?

What is the oxidation state of the osmium atom in an unknown salt if 26.7 grams of osmium plate out when a current of 15.0 amps is passed through a solution of this salt for 1.00 hour?

What is the magnitude of the standard-state cell potential for the following redox reaction? 2 Al(s) + 3 Pb2+(aq) →\rightarrow→ 2 Al3+(aq) + 3 Pb(s)

Use a table of standard reduction potentials to determine which is the strongest oxidizing agent among the following.

refer to the following reaction which occurs in basic solution. CrO42- + PH3 →\rightarrow→ Cr(OH)4- + P4 -How many CrO42- ions are consumed in the balanced chemical equation?

Write a balanced chemical equation for the following reaction, which can be used to standardize aqueous permanganate ion solutions. H2C2O4(aq) + MnO4-(aq) + H+(aq) →\rightarrow→ CO2(g) + Mn2+(aq)

Elements Compounds

The Mole

Structure of the Atom

The Covalent Bond

Ionic and Metallic Bonds

Gases

Making and Breaking of Bonds

Liquids and Solutions

Solids

An Introduction to Kinetics and Equilibrium

Acids and Bases

Chemical Thermodynamics

Kinetics

Nuclear Chemistry

Organic Chemistry

Filters

‪ Determining Oxidation Numbers -Determine the oxidation state of the carbon atom in bold print: CH₃CH₂F

Cobalt(III) oxide reacts with hydrogen gas to form cobalt metal and water. Co₂O₃(s) + 3 H₂(g) $\rightarrow$ 2 Co(s) + 3 H₂O(g) What does this tell you about the relative strength of the oxidizing and reducing agents in this reaction?

An electric current is passed through a solution of CuSO₄(aq) producing Cu(s) at the cathode and O₂(g) at the anode. If 3.48 L of O₂(g) measured at STP is produced at the anode, how many grams of Cu(s) must have been deposited on the cathode?

Calculate the complex dissociation equilibrium constant (K_d) for the Cd(NH₃)₄²⁺ complex from the following data at 298K.

A molten sample of TiCl₄ was electrolyzed for 10.0 hours at 12 amps. What is the ratio of the weight of Cl₂ produced compared to that of Ti?

What is the ratio by weight of Br₂ to Cr if a molten sample of CrBr₂ is electrolyzed for 4.00 hr. at 10.0 amps?

Calculate the amount of aluminum produced in 1.00 hour by the electrolysis of molten AlCl₃ if the current is 10.0 A.

Which of the following electrolysis processes will produce the largest volume of Cl₂ gas at STP?

What is the magnitude of the standard-state cell potential for the following redox reaction? 2 Al(s) + 3 Pb²⁺(aq) $\rightarrow$ 2 Al³⁺(aq) + 3 Pb(s)

refer to the following reaction which occurs in basic solution. CrO₄^2- + PH₃ $\rightarrow$ Cr(OH)₄^- + P₄ -How many CrO₄^2- ions are consumed in the balanced chemical equation?

Write a balanced chemical equation for the following reaction, which can be used to standardize aqueous permanganate ion solutions. H₂C₂O₄(aq) + MnO₄^-(aq) + H⁺(aq) $\rightarrow$ CO₂(g) + Mn²⁺(aq)