Deck 12: Oxidation-Reduction Reactions

Question 1

‪
Determining Oxidation Numbers

-What is the oxidation number of the carbon in bold print in the following structure?

A) -1
B) +2
C) -3
D) +4
E) none of these

Answer 1

+2

Question 2

‪
Determining Oxidation Numbers

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

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

Answer 2

+2

Question 3

?
Determining Oxidation Numbers

-Determine the oxidation number for bromine in HBrO₄.

A) +6
B) +7
C) +8
D) -6
E) -7

Answer 3

+7

Question 4

?
Determining Oxidation Numbers

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

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

Question 5

?
Determining Oxidation Numbers

-Determine the oxidation number of arsenic in the anion, HAsO₄^{2 -} .

A) +5
B) +6
C) +7
D) +8
E) none of these

Question 6

‪
Determining Oxidation Numbers

-Determine the oxidation state of the carbon atom shown in bold in the following compound:

A) -1
B) 0
C) +1
D) +4
E) none of these

Question 7

The carbon in bold in the ethanol has an oxidation number of __ while the carbon in bold in acetic acid has an oxidation number of ___.

A) -1, +3
B) +1, +2
C) -2, +3
D) +2, -3
E) none of the above

Question 8

Which of the following statements about this reaction is correct?

A) H⁺ is the oxidizing agent and dichromate is the reducing agent.
B) Dichromate is oxidized and ethanol is reduced.
C) Ethanol is the reducing agent and dichromate is the oxidizing agent.
D) This is not an oxidation-reduction reaction.
E) None of the above statements is correct.

Question 9

How many electrons are transferred in the following oxidation-reduction reaction?
3 Sn²⁺(aq) + Cr₂O₇^2-(aq) + 14 H⁺ 3 Sn⁴⁺(aq) + 2 Cr³⁺(aq) + 7 H₂O(l)

A) 2
B) 6
C) 12
D) 14
E) none of these

Question 10

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

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 11

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

A) H₂(g) + Cl₂(g) $\rightarrow$ 2 HCl(g)
B) Ag⁺(aq) + 2 NH₃(g) Ag(NH₃)₂⁺(aq)
C) Hg₂Cl₂(s) + NH₃(g) $\rightarrow$ Hg(s) + HgNH₂Cl(s)
D) 2 Mg(s) + O₂(g) $\rightarrow$ 2MgO(s)
E) Cl₂(g) + 2 Br^-(aq) $\rightarrow$ 2 Cl^-(aq) + Br₂(l)

Question 12

A voltaic cell is constructed with a Pt wire in an aqueous solution of Br₂/Br ^- (1M) serving as the cathode and a silver wire in a 1M solution of Ag⁺ serving as the anode. The potential of the cell was measured to be +0.287 V. The standard reduction potential for Br₂/Br ^- is 1.087 V.
(I) Write the half-reaction for the reduction taking place in the cell.
(II) Write the half-reaction for the oxidation taking place in the cell.
(III) Write the overall reaction for the oxidation-reduction reaction taking place in the cell.
(IV) Calculate the potential for the Ag/Ag⁺ half-reaction taking place in the cell.
(V) Determine the standard reduction potential, E°, for the half-reaction below.
Ag⁺(aq) + e- ^{$\rightarrow$} Ag(s)

Question 13

What will be the coefficients of Ce⁴⁺ and Cl ^- , respectively when the following reaction is balanced?
Ce⁴⁺(aq) + Cl ^- (aq) $\rightarrow$ Cl₂(aq) + Ce³⁺(aq)

A) 1,1
B) 1,2
C) 2.1
D) 2.2
E) 3,1

Question 14

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

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 15

Use the table of electrode potentials to determine which of the following reactions isn't spontaneous under standard conditions.

A) Zn(s) + 2 H⁺(aq) $\rightarrow$ Zn²⁺(aq) + H₂(g)
B) 2 Ag(s) + Zn²⁺(aq) $\rightarrow$ 2 Ag⁺(aq) + Zn(s)
C) Cl₂(aq) + 2 Fe²⁺(aq) $\rightarrow$ 2 Cl^-(aq) + 2 Fe³⁺(aq)
D) 2 Al(s) + 3/2 O₂(g) + 6 H⁺(aq) $\rightarrow$ 2 Al³⁺(aq) + 3 H₂O(l)
E) Mg(s) + Cl₂(g) $\rightarrow$ MgCl₂(s)

Question 16

Consider the following generalized half-reactions.
A_ox + e^- A_red
B_ox + e^- B_red
If E° for the half-reaction involving A is positive and if E° for the half-reaction involving B is negative, then at standard conditions:

A) A_ox will reduce B_ox
B) A_red will reduce B_ox
C) B_red will reduce A_ox
D) B_red will reduce A_red
E) no reaction will occur

Question 17

The potential of a cell at standard state conditions can be best be described as:

A) E^o
B) 0 volts
C) negative
D) more than one volt
E) None of the above

Question 18

What is the potential for a voltaic cell produced from the following half-reactions, if all ions are present at 1.0 M concentrations?
Oxidation: Al Al³⁺ + 3 e^-
Reduction: Zn²⁺ + 2 e^- Zn

A) -3.59 V
B) -0.943 V
C) 0.943 V
D) 1.12 V
E) 3.59 V

Question 19

What is the standard cell potential for the following redox reaction?
2 Fe³⁺(aq) + 2 I^-(aq) $\rightarrow$ 2 Fe²⁺(aq) + I₂(aq)

A) -1.30 V
B) -0.24 V
C) 0.24 V
D) 1.30 V
E) none of the above

Question 20

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)

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

Question 21

Oxidation-reduction reactions are often written with double arrows indicating that the reaction can go in either direction depending on the experimental conditions. For the following reaction identify the oxidizing agent on both sides of the chemical equation.
S₂O₈^2-(aq) + Zn(s) Zn²⁺(aq) + 2 SO₄^2-(aq)

A) S₂O₈^2- and SO₄^2-
B) Zn and SO₄^2-
C) Zn and Zn²⁺
D) S₂O₈^2- and Zn²⁺
E) none of these

Question 22

Which statement correctly describes the following oxidation-reduction reaction?
5Cr³⁺(aq) + 3 MnO₄ ^- (aq) + 8 H₂O (l) $\rightarrow$ 5 CrO₄^{2 -} (aq) + 3 Mn²⁺(aq) + 16 H⁺(aq)

A) MnO₄ ^- and H₂O are both reduced.
B) Cr³⁺ is the reducing agent.
C) Cr³⁺ and H₂O are both reducing agents.
D) MnO₄ ^- is oxidized.
E) None of these are correct.

Question 23

Which of the following is true about the reaction below?
2VO²⁺ (aq) + Br₂(s) + 2 H₂O(l) $\rightarrow$ 2VO₂⁺(aq) + 2 Br ^- (aq) + 4H⁺

A) Br₂ is acting as a reducing agent.
B) VO₂⁺ is acting as a weak reducing agent.
C) VO²⁺ is oxidized.
D) H₂O is reduced.
E) H⁺ is acting as a weak reducing agent.

Question 24

Identify each of the requested compounds for the following redox reaction.
2 MnO₄ ^- (aq) + 16 H⁺(aq) + 10 Cl ^- (aq) $\rightarrow$ 2 Mn²⁺(aq) + 8 H₂O + 5 Cl₂(g)
(I) oxidizing agent
(II) reducing agent
(III) conjugate oxidizing agent
(IV) conjugate reducing agent

Question 25

Which statement correctly describes the following reaction?
O₂(g) + 4 H⁺(aq) + 4 Cl ^- (aq) $\rightarrow$ 2 H₂O(l) + 2 Cl₂(g)

A) O₂ is a reducing agent.
B) H⁺ and Cl ^- are oxidized.
C) H⁺ is reduced.
D) H⁺ is a reducing agent.
E) Cl ^- is a reducing agent.

Question 26

For the following reaction, identify the oxidizing agents in the forward and reverse directions, respectively..
P₄(s) + HNO₃(aq) $\rightarrow$ H₃PO₄(aq) + NO(g)

A) P₄ and H₃PO₄
B) P₄ and NO
C) P₄ and HNO₃
D) HNO₃ and H₃PO₄
E) HNO₃ and NO

Question 27

For the reaction:
3 Sn²⁺(aq) + Cr₂O₇^2-(aq) + 14 H⁺(aq) $\rightarrow$ 3 Sn⁴⁺(aq) + 2 Cr³⁺(aq) + 7 H₂O(l)
Which of the following statements is true?

A) Both Sn²⁺ and H⁺ are oxidizing agents.
B) Cr₂O₇^2- is the oxidizing agent.
C) Sn²⁺ is reduced.
D) The acid isn't important to the reaction.
E) None of the above are true.

Question 28

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

A) Co
B) Ca²⁺
C) Co³⁺
D) Cr
E) Au

Question 29

Given the following half-cell reduction potentials, determine which of the following is the strongest reducing agent.

A) In³⁺
B) In
C) Pd²⁺
D) Pd
E) Cannot be determined from cell potentials alone

Question 30

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

A) Ga³⁺
B) Be²⁺
C) Be
D) Pd²⁺
E) Pd

Question 31

Given the following half-cell reduction potentials, determine which metal is the best reducing agent.
Co²⁺ + 2e ^- $\rightarrow$ Co E = -0.28 V
Pd²⁺ + 2e ^- $\rightarrow$ Pd E 11ee9f07_2055_deec_9fac_e13ec1386541_TB9692_11 = +0.987 V
Cd²⁺ + 2e ^- $\rightarrow$ Cd E 11ee9f07_2055_deec_9fac_e13ec1386541_TB9692_11 = -0.403 V

A) Co
B) Pd
C) Cd
D) None would be a good reducing agent.

Question 32

Given the following redox reactions and cell potentials, rank from weakest to strongest the relative strengths of Al, Fe, and Cr as reducing agents. Al(s) + Cr³⁺(aq) $\rightarrow$ Al³⁺(aq) + Cr(s)     E^o = +0.966 V
Fe(s) + Cr³⁺(aq) $\rightarrow$ Fe³⁺(aq) + Cr(s)     E^o = -0.70 V

A) Cr < Fe < Al
B) Al < Fe < Cr
C) Al < Cr < Fe
D) Fe < Cr < Al
E) Fe < Al < Cr

Question 33

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

A) H₂O₂ in base
B) H₂O₂ in acid
C) O₂ in acid
D) CrO₄^2- in acid
E) Br₂

Question 34

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

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 35

Which of the following pairs of ions can't coexist in aqueous solution under standard-state conditions because a spontaneous redox reaction occurs?

A) Sn⁴⁺ and Fe³⁺
B) Sn⁴⁺ and Fe²⁺
C) Sn²⁺ and Fe³⁺
D) Sn²⁺ and Fe²⁺
E) None of these pairs of ions can coexist.

Question 36

Which is the strongest oxidizing agent?

A) Ce⁴⁺
B) Ce³⁺
C) H⁺
D) Cr²⁺
E) Mg

Question 37

Which of the following reagents should react with H⁺ to produce H₂?

A) either Mg²⁺ and Cr²⁺
B) either Pd and Cr²⁺
C) either Pd²⁺
D) either Mg and Cr
E) Mg, Cr, and Pd

Question 38

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

A) Cu²⁺ and Zn²⁺
B) Fe³⁺ and Hg₂²⁺
C) Cu²⁺ and I^-
D) Al³⁺ and S^2-
E) All of these pairs of ions can coexist.

Question 39

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?

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 40

The equilibrium constant at 298 K for the following reaction is 1.2 x 10⁵.
H₂(g) + Sn⁴⁺(aq) $\rightarrow$ 2 H⁺(aq) + Sn²⁺(aq)
What is the value of E° for the reaction?

A) -0.15 V
B) 0.15 V
C) 0.30 V
D) 0.35 V
E) 0.45 V

Question 41

The equilibrium constant at 25 ^oC for the following reaction is 2 x 10^-3.
H₂(g) + 2Ru³⁺(aq) $\rightarrow$ 2 H⁺(aq) + 2Ru²⁺(aq)
What is the value of E° for the reaction?

A) -0.16 V
B) 0.16 V
C) 1.00 V
D) 0.00 V
E) -0.08 V

Question 42

Calculate the value of the K_sp for CdS at 25 °C from the following data.
CdS + 2 e^- Cd + S^2-     E° = -1.21 V
Cd²⁺ + 2 e^- Cd     E° = -0.40 V

A) 3 x 10^-55
B) 4 x 10^-28
C) 2 x 10^-14
D) 3 x 10²⁷
E) 6 x 10

Question 43

There are two half-reactions for the reduction of O₂ to H₂O.

Use these half-reactions to calculate the ionization constant for water, K_w,
at 25 °C.
H₂O(l) H⁺(aq) + OH^-(aq) K_w = ?

Question 44

The half-reaction reduction potentials for the mercury(I) and silver(I) ions are given below.

Question 45

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

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

Question 46

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.

Question 47

What is the ratio of the weight of Cl₂ produced at the anode to the weight of Al produced at the cathode when 5 moles of electrons are passed through a molten sample of AlCl₃?

A) about 2 g Cl₂ per 1 g Al
B) about 4 g Cl₂ per 1 g Al
C) about 8 g Cl₂ per 1 g Al
D) about 16 g Cl₂ per 1 g Al
E) none of the above

Question 48

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

Question 49

Suppose a beer can weighs 40.0 g. Determine the amount of time in hours that a current of 100.0 amp need to be passed through a molten AlF₃ electrolysis cell to produce enough Al to replace a discarded beer can. Sketch the electrolysis cell, labeling the electrodes and showing the direction of electron flow in the external circuit as part of your answer.

Question 50

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

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 51

A current of 1.5 amps is applied to a 1.00 L solution of 0.100 M hydrochloric acid for 1.0 hr. What is the pH of the solution after electrolysis is complete?

Question 52

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?

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 53

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?

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

Question 54

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?

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 55

How much Cl₂ gas would be collected when a 2.00 M NaCl(aq) solution is electrolyzed for 2.00 hours with a current of 15.0 amps?

A) 0.0220 g
B) 39.7 g
C) 79.4 g
D) 159 g
E) none of the above

Question 56

A current of 10.0 amps over a period of 3.00 hr is passed through a solution of molten KCl. What weight of K metal is produced?

A) 0.365 g
B) 0.729 g
C) 21.9 g
D) 43.8 g
E) 87.5 g

Question 57

A current of 2.0 amps passed through a molten solution of the salt MCl₂ for a period of 30 minutes produces 1.32 g of Cl₂ gas and 0.453 g of M. Which of the following metals is present in this compound?

A) Mg
B) Ca
C) Zn
D) Sr
E) Hg

Question 58

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?

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

Question 59

What is the oxidation state of the cerium atom in Ce_xZ_y if a current of 1.2 amps for 3.0 hours deposits 4.70 g of Ce at the cathode?

A) 0
B) +1
C) +2
D) +3
E) +4

Question 60

What is the oxidation state of the tin atom in an unknown salt if 14.8 grams of tin are plated out when a current of 40 amps is passed through a molten solution of this salt for 10 minutes?

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

Question 61

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

A) SO₄^2-(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) SO₄^2-(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 62

Which of the following statements about the electrolysis of an aqueous solution of NaCl is true?

A) O₂ is liberated at the cathode.
B) H₂ is liberated at the cathode.
C) Na is liberated at the cathode.
D) Cl₂ is liberated at the cathode.
E) The decomposition potential must not be exceeded.

Question 63

In the electrolysis of NaBr(aq), which of the following products is least likely to be found?

A) H₂(g)
B) O₂(g)
C) Br₂(l)
D) Na(s)
E) NaOH(aq)

Question 64

What is the correct coefficient for Na₂MnO₄ in the balanced equation for the air oxidation of manganese dioxide to sodium manganate in the presence of sodium carbonate?
MnO₂(s) + Na₂CO₃(aq) + O₂(g) $\rightarrow$ CO₂(g) + Na₂MnO₄(aq)

A) 1
B) 3/2
C) 2
D) 5/2
E) 3

Question 65

What is the coefficient for sulfur in the following redox reaction?
S(s) + KClO₃(s) $\rightarrow$ SO₂(g) + KCl(s) + bang!

A) 1
B) 2
C) 3
D) 4
E) 5

Question 66

The following equation, when balanced, involves a total of ___ electrons.
ClO₃^-(aq) + I₂(aq) + H₂O(l) $\rightarrow$ IO₃^-(aq) + Cl^-(aq) + H⁺(aq)

A) 5
B) 6
C) 12
D) 24
E) 30

Question 67

Complete and balance the following equation:
PbO₂(s) + Cl^-(aq) + H⁺(aq) $\rightarrow$ Pb²⁺(aq) + Cl₂(aq)

Question 68

refer to the following reaction in acid solution.
CuS(s) + NO₃^-(aq) Cu²⁺(aq) + SO₄^2-(aq) + NO(g)

-In the balanced half-reaction for the NO₃^- ion, how many electrons are involved?

A) 1
B) 2
C) 3
D) 4
E) none of these

Question 69

Which of the following isn't true?

A) The reducing agent is CuS.
B) The CuS is oxidized.
C) The NO₃^- ion is the oxidizing agent.
D) The NO₃^- ion is reduced.
E) The oxidation number of the copper changes from 0 to +2.

Question 70

Write a balanced chemical equation for the following reaction.
MnO₂(s) + PbO₂(s) + H⁺(aq) $\rightarrow$ MnO₄^-(aq) + Pb²⁺(aq)

Question 71

refer to the following incomplete, unbalanced equation
Cr₂O₇^2-(aq) + NO(g)
Cr³⁺(aq) + NO₃^-(aq)

-How many electrons are in the half-reaction involving Cr₂O₇^2-?

A) 2
B) 3
C) 4
D) 5
E) 6

Question 72

refer to the following incomplete, unbalanced equation
Cr₂O₇^2-(aq) + NO(g)
Cr³⁺(aq) + NO₃^-(aq)

-What is the coefficient of the NO in the balanced equation?

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

Question 73

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)

Question 74

Balance the following redox reaction. Clearly show the two balanced half-reactions and indicate which represents oxidation and which reduction.
H₂O₂(aq) + NO(g) + H⁺(aq) $\rightarrow$ NO₃^-(aq)

Question 75

Balance the following oxidation-reduction equation.
HI(aq) + HNO₃(aq) $\rightarrow$ NO(g) + I₂(aq)

Question 76

Balance the following oxidation-reduction equation.
CrO₄^2-(aq) + HSnO₂^-(aq)

HSnO₃^-(aq) + CrO₂^-(aq)

Question 77

Redox Reactions in Basic Solutions
refer to the following reaction which occurs in basic solution:
OCl^-(aq) $\rightarrow$ ClO₂^-(aq) + Cl₂(aq)

-How many OCl^- ions are consumed in the balanced equation for this reaction?

A) 2
B) 3
C) 4
D) 5
E) 6

Question 78

Redox Reactions in Basic Solutions
refer to the following reaction which occurs in basic solution:
OCl^-(aq) $\rightarrow$ ClO₂^-(aq) + Cl₂(aq)

-How many OH^- ions are involved in the simplest balanced equation for this reaction?

A) 0
B) 1
C) 2
D) 3
E) 4

Question 79

Redox Reactions in Basic Solutions
refer to the following reaction which occurs in basic solution:
OCl^-(aq) $\rightarrow$ ClO₂^-(aq) + Cl₂(aq)

-What is the net effect on the OH^- ion concentration in this reaction?

A) The OH^- ion concentration increases.
B) The OH^- ion concentration decreases.
C) The OH^- ion concentration remains the same.
D) There is no way to predict what happens to the OH^- ion concentration in this reaction.

Question 80

refer to the following reaction which occurs in basic solution.
CrO₄^2- + PH₃ $\rightarrow$ Cr(OH)₄^- + P₄

-Which of the following are oxidizing agents in the forward and reverse directions, respectively?

A) CrO₄^2- and PH₃
B) CrO₄^2- and P₄
C) Cr(OH)₄^- and PH₃
D) Cr(OH)₄^- and P₄
E) CrO₄^2- and OH^-