Question 1

In order for an oxidation reaction to occur, a reduction reaction must also take place.

Accepted Answer

A) True 
 B)False

Question 2

The most reactive metals are those of

Accepted Answer

A) Group IA (Group 1). 
B) Group IIA (Group 2). 
C) Group IIIA (Group 13). 
D) Group IB (Group 11). 
E) Group IIB (Group 12). 
A) Group IA (Group 1). 
B) Group IIA (Group 2). 
C) Group IIIA (Group 13). 
D) Group IB (Group 11). 
E) Group IIB (Group 12).

Question 3

The nitrogen molecule, (N2), was involved in a chemical reaction in which it underwent reduction. Based on the change in oxidation numbers, which of the species listed below is a possible product of the reaction?

Accepted Answer

A) N2H4  
B) NO 
C) NO2- 
D) NO2 
E) NO3- 
A) N2H4  
B) NO 
C) NO2- 
D) NO2 
E) NO3-

Question 4

The following reaction describes the decomposition of NaHCO3, baking soda:2NaHCO3 $\rarr$ Na2CO3 + CO2 + H2O This is not an oxidation-reduction reaction, since nothing is oxidized or reduced.

Accepted Answer

A) True 
 B)False

Question 5

Which of the following involves reduction?

Accepted Answer

A) Ba2+(aq)+ CrO42-(aq)$\rarr$ BaCrO4(s) 
B) 2 H+(aq)+ CO32-(aq)$\rarr$H2O(l)+ CO2(g) 
C) CrO42-(aq)$\rarr$ Cr3+(aq) 
D) MnO2(s)$\rarr$ MnO4-(aq) 
E) 2 CrO42-(aq)+ 2 H+(aq)$\rarr$Cr2O72-(aq)+ H2O(l) 
A) Ba2+(aq)+ CrO42-(aq)$\rarr$ BaCrO4(s) 
B) 2 H+(aq)+ CO32-(aq)$\rarr$H2O(l)+ CO2(g) 
C) CrO42-(aq)$\rarr$ Cr3+(aq) 
D) MnO2(s)$\rarr$ MnO4-(aq) 
E) 2 CrO42-(aq)+ 2 H+(aq)$\rarr$Cr2O72-(aq)+ H2O(l)

Question 6

When H2O2 behaves as a reducing agent, the most likely product formed from it is ________. Hint: Write out an example equation with H2O2 being oxidized to see the result.

Accepted Answer

Question 7

The reaction, AgNO3(aq)+ NH4Br(aq)$\rarr$ AgBr(s)+ NH4NO3(aq), involves changes in oxidation number and is therefore classified as a redox reaction.

Accepted Answer

A) True 
 B)False

Question 8

Complete the balancing of the following half-reaction, taking place in basic media. How many hydroxide ions are needed to balance the half-reaction?Br(aq)s BrO3(aq)Hint: Remember the coefficients when balancing half-reactions and look carefully at the oxidation numbers.

Accepted Answer

A) 2 hydroxide ions, on the left side 
B) 4 hydroxide ions, on the left side 
C) 4 hydroxide ions, on the right side 
D) 6 hydroxide ions, on the left side 
E) 6 hydroxide ions, on the right side 
A) 2 hydroxide ions, on the left side 
B) 4 hydroxide ions, on the left side 
C) 4 hydroxide ions, on the right side 
D) 6 hydroxide ions, on the left side 
E) 6 hydroxide ions, on the right side

Question 9

When the equation, Al(s)+ NO3-(aq)→ NO(g)+ Al3+(aq)is balanced for an acidic solution, the sum of ALL the coefficients is ________. Hint: Do not neglect to include electrons when balancing redox reactions.

Accepted Answer

Question 10

A partial activity series is: Au 2 < Sn < Co < Fe < Mg. Based on this series, which of the following solutions would cause a reaction with Cu(s)?

Accepted Answer

Question 11

When a copper metal reacts with aqueous nitric acid, which substance is the oxidizing agent?

Accepted Answer

The answer of When a copper metal reacts with aqueous...

Question 12

The CrO42- ion was involved in a chemical reaction, during which it is transformed into Cr3+ ions. What is the change in oxidation number of the chromium atom?

Accepted Answer

A) The oxidation number increases by 5 units. 
B) The oxidation number decreases by 5 units. 
C) The oxidation number increases by 1 unit. 
D) The oxidation number decreases by 3 units. 
E) The oxidation number decrease by 4 units. 
A) The oxidation number increases by 5 units. 
B) The oxidation number decreases by 5 units. 
C) The oxidation number increases by 1 unit. 
D) The oxidation number decreases by 3 units. 
E) The oxidation number decrease by 4 units.

Question 13

Balance the half-reaction, C2H6O $\rarr$HC2H3O2, taking place in acidic media. How many electrons are needed to balance the charge?Hint: Remember the coefficients when balancing half-reactions and look carefully at the oxidation numbers.

Accepted Answer

A) 2 electrons, left side 
B) 3 electrons, left side 
C) 4 electrons, right side 
D) 6 electrons, right side 
E) 8 electrons, right side 
A) 2 electrons, left side 
B) 3 electrons, left side 
C) 4 electrons, right side 
D) 6 electrons, right side 
E) 8 electrons, right side

Question 14

The ClO2 molecule was involved in a chemical reaction in which it underwent oxidation. Based on the change in oxidation numbers, which of the species listed below is a possible product of the reaction?

Accepted Answer

A) ClO- 
B) Cl- 
C) ClO2- 
D) Cl2 
E) ClO3- 
A) ClO- 
B) Cl- 
C) ClO2- 
D) Cl2 
E) ClO3-

Question 15

Balance the redox reaction below in acidic solution.Cl2(g)→ Cl-(aq)+ ClO-(aq)When balanced, what is the sum of all the coefficients? Hint: Consider your oxidation numbers when balancing redox reactions.

Accepted Answer

Question 16

Balance the redox reaction below in basic solution.PbO2(s)+ I-(aq)→ Pb2+(aq)+ I2(s)What is the coefficient of OH- in the final balanced equation? Hint: Consider your oxidation numbers when balancing redox reactions.

Accepted Answer

Question 17

Which of the following involves oxidation?

Accepted Answer

A) Ca2+(aq)+ CO32-(aq)$\rarr$ CaCO3(s) 
B) 2 H+(aq)+ SO32-(aq)$\rarr$H2O(l)+ SO2(g) 
C) VO43-(aq)$\rarr$ VO2+(aq) 
D) CrO2- (aq)$\rarr$CrO42-(aq) 
E) 2 S2O72-(aq)+ H2O(l)$\rarr$ 2 SO42-(aq)+ 2 H+(aq) 
A) Ca2+(aq)+ CO32-(aq)$\rarr$ CaCO3(s) 
B) 2 H+(aq)+ SO32-(aq)$\rarr$H2O(l)+ SO2(g) 
C) VO43-(aq)$\rarr$ VO2+(aq) 
D) CrO2- (aq)$\rarr$CrO42-(aq) 
E) 2 S2O72-(aq)+ H2O(l)$\rarr$ 2 SO42-(aq)+ 2 H+(aq)

Question 18

The following chemical equation shows how water can be produced.
 H2(g)+ ½ O2(g)$\rarr$H2O(l)In the reaction, hydrogen is the species which is reduced.

Accepted Answer

A) True 
 B)False

Question 19

Hot concentrated sulfuric acid is a good oxidizing agent.

Accepted Answer

A) True 
 B)False

Question 20

Zinc metal reacts with perchloric acid solution to produce aqueous zinc perchlorate and hydrogen gas, which escapes. The species being oxidized in this reaction is

Accepted Answer

A) HClO4(aq). 
B) H2(g). 
C) Zn2+(aq). 
D) Zn(s). 
E) Zn(ClO4)2(aq). 
A) HClO4(aq). 
B) H2(g). 
C) Zn2+(aq). 
D) Zn(s). 
E) Zn(ClO4)2(aq).

Exam 6: Oxidation-Reduction Reactions

In order for an oxidation reaction to occur, a reduction reaction must also take place.

The most reactive metals are those of

The nitrogen molecule, (N2), was involved in a chemical reaction in which it underwent reduction. Based on the change in oxidation numbers, which of the species listed below is a possible product of the reaction?

The following reaction describes the decomposition of NaHCO3, baking soda:2NaHCO3 →\rarr→ Na2CO3 + CO2 + H2O This is not an oxidation-reduction reaction, since nothing is oxidized or reduced.

Which of the following involves reduction?

When H2O2 behaves as a reducing agent, the most likely product formed from it is ________. Hint: Write out an example equation with H2O2 being oxidized to see the result.

The reaction, AgNO3(aq)+ NH4Br(aq) →\rarr→ AgBr(s)+ NH4NO3(aq), involves changes in oxidation number and is therefore classified as a redox reaction.

Complete the balancing of the following half-reaction, taking place in basic media. How many hydroxide ions are needed to balance the half-reaction?Br(aq)s BrO3(aq)Hint: Remember the coefficients when balancing half-reactions and look carefully at the oxidation numbers.

When the equation, Al(s)+ NO3-(aq)→ NO(g)+ Al3+(aq)is balanced for an acidic solution, the sum of ALL the coefficients is ________. Hint: Do not neglect to include electrons when balancing redox reactions.

A partial activity series is: Au < Pt < Ag < Cu < H2 < Sn < Co < Fe < Mg. Based on this series, which of the following solutions would cause a reaction with Cu(s)?

When a copper metal reacts with aqueous nitric acid, which substance is the oxidizing agent?

The CrO42- ion was involved in a chemical reaction, during which it is transformed into Cr3+ ions. What is the change in oxidation number of the chromium atom?

Balance the half-reaction, C2H6O →\rarr→ HC2H3O2, taking place in acidic media. How many electrons are needed to balance the charge?Hint: Remember the coefficients when balancing half-reactions and look carefully at the oxidation numbers.

The ClO2 molecule was involved in a chemical reaction in which it underwent oxidation. Based on the change in oxidation numbers, which of the species listed below is a possible product of the reaction?

Balance the redox reaction below in acidic solution.Cl2(g)→ Cl-(aq)+ ClO-(aq)When balanced, what is the sum of all the coefficients? Hint: Consider your oxidation numbers when balancing redox reactions.

Balance the redox reaction below in basic solution.PbO2(s)+ I-(aq)→ Pb2+(aq)+ I2(s)What is the coefficient of OH- in the final balanced equation? Hint: Consider your oxidation numbers when balancing redox reactions.

Which of the following involves oxidation?

The following chemical equation shows how water can be produced. H2(g)+ ½ O2(g) →\rarr→ H2O(l)In the reaction, hydrogen is the species which is reduced.

Hot concentrated sulfuric acid is a good oxidizing agent.

Zinc metal reacts with perchloric acid solution to produce aqueous zinc perchlorate and hydrogen gas, which escapes. The species being oxidized in this reaction is

A Very Brief History of Chemistry

Scientific Measurements

Elements, Compounds, and the Periodic Table

The Mole and Stoichiometry

Molecular View of Reactions in Aqueous Solutions

Energy and Chemical Change

The Quantum Mechanical Atom

The Basics of Chemical Bonding

Theories of Bonding and Structure

Properties of Gases

Intermolecular Attractions and the Properties of Liquids and Solids

Mixtures at the Molecular Level: Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases, a Molecular Look

Acid-Base Equilibria in Aqueous Solutions

Solubility and Simultaneous Equilibria

Thermodynamics

Electrochemistry

Nuclear Reactions and Their Role in Chemistry

Metal Complexes

Organic Compounds, Polymers, and Biochemicals

Filters

The nitrogen molecule, (N₂), was involved in a chemical reaction in which it underwent reduction. Based on the change in oxidation numbers, which of the species listed below is a possible product of the reaction?

The following reaction describes the decomposition of NaHCO₃, baking soda:2NaHCO₃ $\rarr$ Na₂CO₃ + CO₂ + H₂O This is not an oxidation-reduction reaction, since nothing is oxidized or reduced.

When H₂O₂ behaves as a reducing agent, the most likely product formed from it is ________. Hint: Write out an example equation with H₂O₂ being oxidized to see the result.

The reaction, AgNO₃(aq)+ NH₄Br(aq) $\rarr$ AgBr(s)+ NH₄NO₃(aq), involves changes in oxidation number and is therefore classified as a redox reaction.

Complete the balancing of the following half-reaction, taking place in basic media. How many hydroxide ions are needed to balance the half-reaction?Br(aq)s BrO₃(aq)Hint: Remember the coefficients when balancing half-reactions and look carefully at the oxidation numbers.

When the equation, Al(s)+ NO₃^-(aq)→ NO(g)+ Al³⁺(aq)is balanced for an acidic solution, the sum of ALL the coefficients is ________. Hint: Do not neglect to include electrons when balancing redox reactions.

A partial activity series is: Au < Pt < Ag < Cu < H₂ < Sn < Co < Fe < Mg. Based on this series, which of the following solutions would cause a reaction with Cu(s)?

The CrO₄^2- ion was involved in a chemical reaction, during which it is transformed into Cr³⁺ ions. What is the change in oxidation number of the chromium atom?

Balance the half-reaction, C₂H₆O $\rarr$ HC₂H₃O₂, taking place in acidic media. How many electrons are needed to balance the charge?Hint: Remember the coefficients when balancing half-reactions and look carefully at the oxidation numbers.

The ClO₂ molecule was involved in a chemical reaction in which it underwent oxidation. Based on the change in oxidation numbers, which of the species listed below is a possible product of the reaction?

Balance the redox reaction below in acidic solution.Cl₂(g)→ Cl^-(aq)+ ClO^-(aq)When balanced, what is the sum of all the coefficients? Hint: Consider your oxidation numbers when balancing redox reactions.

Balance the redox reaction below in basic solution.PbO₂(s)+ I^-(aq)→ Pb²⁺(aq)+ I₂(s)What is the coefficient of OH^- in the final balanced equation? Hint: Consider your oxidation numbers when balancing redox reactions.

The following chemical equation shows how water can be produced. H₂(g)+ ½ O₂(g) $\rarr$ H₂O(l)In the reaction, hydrogen is the species which is reduced.