Introductory Chemistry: A Foundation
Introductory Chemistry: A Foundation
9th Edition
ISBN: 9781337399425
Author: Steven S. Zumdahl, Donald J. DeCoste
Publisher: Cengage Learning
bartleby

Videos

Textbook Question
Book Icon
Chapter 18, Problem 45QAP

. Balance each of the following oxidation-reduction reactions, which take place in acidic solution, by using the “half-reaction” method.

a. Mg ( s ) + Hg 2 + ( aq ) Mg 2 + ( aq ) + Hg 2 2 + ( aq )    b. NO 3 ( aq ) + Br ( aq ) NO ( g ) + Br 2 ( l )    c. Ni ( s ) + NO ( aq ) Ni 2 + ( aq ) + NO 2 ( g )    d. ClO 4 ( aq ) + Cl ( aq ) ClO 3 ( aq ) + Cl 2 ( g )

Expert Solution
Check Mark
Interpretation Introduction

(a)

Interpretation:

The given oxidation-reduction reaction should be balanced using the half-reaction method.

Concept Introduction:

The oxidation-reduction reaction is also known as a redox reaction. In this reaction, one reactant is oxidized and other is reduced. In balancing an oxidation-reduction reaction they must be first divided into two half reactions: one is oxidation reaction and other is reduction reaction.

The balancing of redox reaction is complicated as compared to simple balancing. It is necessary to determine the half reactions of reactants undergoing oxidation and reduction. On adding the two half-reactions, net total equation can be obtained. This method of balancing redox reaction is known as half equation method.

The following rules must be followed in balancing redox reaction by half equation method:

  1. Initially, redox reaction is separated into two half equations; oxidation and reduction.
  2. Atoms other than hydrogen and oxygen are balanced first in the unbalanced half equations.
  3. Oxygen atoms are balanced by addition of water on either side of the reaction.
  4. Hydrogen ion/s is added to balance the hydrogen atom.
  5. Electrons are added to balance the charge.
  6. Half reactions are added to get the net total equation.
  7. The further addition of hydroxide ion takes place on both side of the reaction, if the solution is basic in nature to neutralise the hydrogen ion present in the solution.

Answer to Problem 45QAP

Mgs+2Hg2+aqMg2+aq+Hg22+aq.

Explanation of Solution

The given reaction is as follows:

Mgs+Hg2+aqMg2+aq+Hg22+aq

First step is to separate the two half reaction,

MgsMg2+aq....... (1)

And,

Hg2+aqHg22+aq...... (2)

Now to balance reaction (1), there is + 2 charge on right thus, two electrons are added thus,

MgsMg2+aq+2e...... (3)

The atom other than hydrogen and oxygen must be balanced first. Thus, coefficient 2 should be given to mercury in reaction (2) thus,

2Hg2+aqHg22+aq

Next step is to balance the charge, since, there is + 4 charge on left and + 2 charge on right thus, 2 electrons should be added to left thus,

2Hg2+aq+2eHg22+aq........ (4)

Now, adding reaction (3) and (4) to get the net overall reaction,

MgsMg2+aq+2e2Hg2+aq+2eHg22+aqMgs+2Hg2+aqMg2+aq+Hg22+aq¯¯

Thus, the balanced reaction by half reaction method will be:

Mgs+2Hg2+aqMg2+aq+Hg22+aq.

Expert Solution
Check Mark
Interpretation Introduction

(b)

Interpretation:

The given oxidation-reduction reaction should be balanced using the half-reaction method.

Concept Introduction:

The oxidation-reduction reaction is also known as a redox reaction. In this reaction, one reactant is oxidized and other is reduced. In balancing an oxidation-reduction reaction they must be first divided into two half reactions: one is oxidation reaction and other is reduction reaction.

The balancing of redox reaction is complicated as compared to simple balancing. It is necessary to determine the half reactions of reactants undergoing oxidation and reduction. On adding the two half-reactions, net total equation can be obtained. This method of balancing redox reaction is known as half equation method.

The following rules must be followed in balancing redox reaction by half equation method:

  1. Initially, redox reaction is separated into two half equations; oxidation and reduction.
  2. Atoms other than hydrogen and oxygen are balanced first in the unbalanced half equations.
  3. Oxygen atoms are balanced by addition of water on either side of the reaction.
  4. Hydrogen ion/s is added to balance the hydrogen atom.
  5. Electrons are added to balance the charge.
  6. Half reactions are added to get the net total equation.
  7. The further addition of hydroxide ion takes place on both side of the reaction, if the solution is basic in nature to neutralise the hydrogen ion present in the solution.

Answer to Problem 45QAP

2NO3aq+8H+aq+6Braq2NOg+4H2Ol+3Br2.

Explanation of Solution

The given reaction is as follows:

NO3aq+BraqNOg+Br2l

First step is to separate the two half reaction,

NO3aqNOg....... (1)

And,

BraqBr2l...... (2)

First reaction 1 is balanced by adding 2 water molecule on right thus,

NO3aqNOg+2H2Ol

Now, to balance hydrogen atom, 4 hydrogen ions should be added on left thus,

NO3aq+4H+aqNOg+2H2Ol

Last step is to balance the charge, thus, one electron is added to left side of the reaction arrow.

NO3aq+4H+aq+3eNOg+2H2Ol..... (3)

Now to balance reaction (1), brome atom is balanced first by giving coefficient 2 to Br as follows:

2BraqBr2l

To balance the charge, 2 electrons must be added to right side of the reaction arrow:

2BraqBr2l+2e..... (4)

Now, adding reaction (3) and (4) to get the net overall reaction,

2×NO3aq+4H+aq+3eNOg+2H2Ol       3×2BraqBr2l+2e2NO3aq+8H+aq+6Braq2NOg+4H2Ol+3Br2l¯¯

Thus, the balanced reaction by half reaction method will be:

2NO3aq+8H+aq+6Braq2NOg+4H2Ol+3Br2.

Expert Solution
Check Mark
Interpretation Introduction

(c)

Interpretation:

The given oxidation-reduction reaction should be balanced using the half-reaction method.

Concept Introduction:

The oxidation-reduction reaction is also known as a redox reaction. In this reaction, one reactant is oxidized and other is reduced. In balancing an oxidation-reduction reaction they must be first divided into two half reactions: one is oxidation reaction and other is reduction reaction.

The balancing of redox reaction is complicated as compared to simple balancing. It is necessary to determine the half reactions of reactants undergoing oxidation and reduction. On adding the two half-reactions, net total equation can be obtained. This method of balancing redox reaction is known as half equation method.

The following rules must be followed in balancing redox reaction by half equation method:

  1. Initially, redox reaction is separated into two half equations; oxidation and reduction.
  2. Atoms other than hydrogen and oxygen are balanced first in the unbalanced half equations.
  3. Oxygen atoms are balanced by addition of water on either side of the reaction.
  4. Hydrogen ion/s is added to balance the hydrogen atom.
  5. Electrons are added to balance the charge.
  6. Half reactions are added to get the net total equation.
  7. The further addition of hydroxide ion takes place on both side of the reaction, if the solution is basic in nature to neutralise the hydrogen ion present in the solution.

Answer to Problem 45QAP

2NO3aq+8H+aq+6Braq2NOg+4H2Ol+3Br2.

Explanation of Solution

The given reaction is as follows:

Nis+NO3aqNi2+aq+NO2g

First step is to separate the two half reaction,

NO3aqNOg....... (1)

And,

BraqBr2l...... (2)

First reaction 1 is balanced by adding 2 water molecule on right thus,

NO3aqNOg+2H2Ol

Now, to balance hydrogen atom, 4 hydrogen ions should be added on left thus,

NO3aq+4H+aqNOg+2H2Ol

Last step is to balance the charge, thus, one electron is added to left side of the reaction arrow.

NO3aq+4H+aq+3eNOg+2H2Ol..... (3)

Now to balance reaction (2), bromine atom is balanced first by giving coefficient 2 to Br as follows:

2BraqBr2l

To balance the charge, 2 electrons must be added to right side of the reaction arrow:

2BraqBr2l+2e..... (4)

Now, adding reaction (3) and (4) to get the net overall reaction,

2×NO3aq+4H+aq+3eNOg+2H2Ol       3×2BraqBr2l+2e2NO3aq+8H+aq+6Braq2NOg+4H2Ol+3Br2l¯¯

Thus, the balanced reaction by half reaction method will be:

2NO3aq+8H+aq+6Braq2NOg+4H2Ol+3Br2.

Expert Solution
Check Mark
Interpretation Introduction

(d)

Interpretation:

The given oxidation-reduction reaction should be balanced using the half-reaction method.

Concept Introduction:

The oxidation-reduction reaction is also known as a redox reaction. In this reaction, one reactant is oxidized and other is reduced. In balancing an oxidation-reduction reaction they must be first divided into two half reactions: one is oxidation reaction and other is reduction reaction.

The balancing of redox reaction is complicated as compared to simple balancing. It is necessary to determine the half reactions of reactants undergoing oxidation and reduction. On adding the two half-reactions, net total equation can be obtained. This method of balancing redox reaction is known as half equation method.

The following rules must be followed in balancing redox reaction by half equation method:

  1. Initially, redox reaction is separated into two half equations; oxidation and reduction.
  2. Atoms other than hydrogen and oxygen are balanced first in the unbalanced half equations.
  3. Oxygen atoms are balanced by addition of water on either side of the reaction.
  4. Hydrogen ion/s is added to balance the hydrogen atom.
  5. Electrons are added to balance the charge.
  6. Half reactions are added to get the net total equation.
  7. The further addition of hydroxide ion takes place on both side of the reaction, if the solution is basic in nature to neutralise the hydrogen ion present in the solution.

Answer to Problem 45QAP

ClO4aq+2H+aq+2ClaqClO3aq+H2Ol+Cl2g.

Explanation of Solution

The given reaction is as follows:

ClO4aq+ClaqClO3aq+Cl2g

First step is to separate the two half reaction,

ClO4aqClO3aq....... (1)

And,

ClaqCl2g...... (2)

In reaction (1), ClO4aq is reduced to ClO3aq from + 7 oxidation state to + 5 oxidation state. To balance the reaction (1), 1 water molecule is added to right side of the reaction arrow as follows:

ClO4aqClO3aq+H2Ol

Now, to balance hydrogen atom, 2 hydrogen ions are added to left side of the reaction arrow:

ClO4aq+2H+aqClO3aq+H2Ol

Last step is to balance the charge, thus, 2 electrons are added to the left side of the reaction arrow to balance the charge in above reaction

ClO4aq+2H+aq+2eClO3aq+H2Ol...... (3)

Now to balance reaction (2), chlorine atom is balanced first by giving coefficient 2 to Cl as follows:

2ClaqCl2g

To balance the charge, 2 electrons must be added to right side of the reaction arrow:

2ClaqCl2g+2e..... (4)

Now, adding reaction (3) and (4) to get the net overall reaction,

ClO4aq+2H+aq+2eClO3aq+H2Ol2ClaqCl2g+2eClO4aq+2H+aq+2ClaqClO3aq+H2Ol+Cl2g¯¯

Thus, the balanced reaction by half reaction method will be:

ClO4aq+2H+aq+2ClaqClO3aq+H2Ol+Cl2g.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Chapter 18 Solutions

Introductory Chemistry: A Foundation

Ch. 18 - Prob. 5ALQCh. 18 - Prob. 6ALQCh. 18 - In balancing oxidation-reduction equations, why is...Ch. 18 - What does it mean for a substance to be oxidized?...Ch. 18 - Label the following parts of the galvanic cell....Ch. 18 - Prob. 1QAPCh. 18 - Prob. 2QAPCh. 18 - For each of the following oxidation-reduction...Ch. 18 - For each of the following oxidation-reduction...Ch. 18 - For each of the following oxidation-reduction...Ch. 18 - Prob. 6QAPCh. 18 - Prob. 7QAPCh. 18 - Prob. 8QAPCh. 18 - Explain why, although it is not an ionic compound,...Ch. 18 - Prob. 10QAPCh. 18 - Prob. 11QAPCh. 18 - Prob. 12QAPCh. 18 - Prob. 13QAPCh. 18 - . Assign oxidation states to all of the atoms in...Ch. 18 - Prob. 15QAPCh. 18 - Prob. 16QAPCh. 18 - . What is the oxidation state of chlorine in each...Ch. 18 - . What is the oxidation state of manganese in each...Ch. 18 - Prob. 19QAPCh. 18 - Prob. 20QAPCh. 18 - Prob. 21QAPCh. 18 - Prob. 22QAPCh. 18 - Prob. 23QAPCh. 18 - Prob. 24QAPCh. 18 - Prob. 25QAPCh. 18 - Prob. 26QAPCh. 18 - . Does an oxidizing agent donate or accept...Ch. 18 - Prob. 28QAPCh. 18 - Prob. 29QAPCh. 18 - Prob. 30QAPCh. 18 - Prob. 31QAPCh. 18 - Prob. 32QAPCh. 18 - Prob. 33QAPCh. 18 - Prob. 34QAPCh. 18 - Prob. 35QAPCh. 18 - Prob. 36QAPCh. 18 - Prob. 37QAPCh. 18 - Prob. 38QAPCh. 18 - Prob. 39QAPCh. 18 - Prob. 40QAPCh. 18 - Prob. 41QAPCh. 18 - Prob. 42QAPCh. 18 - Prob. 43QAPCh. 18 - Prob. 44QAPCh. 18 - . Balance each of the following...Ch. 18 - Prob. 46QAPCh. 18 - . Iodide ion, I- , is one of the most easily...Ch. 18 - Prob. 48QAPCh. 18 - Prob. 49QAPCh. 18 - Prob. 50QAPCh. 18 - . In which direction do electrons flow in a...Ch. 18 - Prob. 52QAPCh. 18 - . Consider the oxidation-reduction reaction...Ch. 18 - . Consider the oxidation—reduction reaction...Ch. 18 - Prob. 55QAPCh. 18 - Prob. 56QAPCh. 18 - Prob. 57QAPCh. 18 - Prob. 58QAPCh. 18 - Prob. 59QAPCh. 18 - Prob. 60QAPCh. 18 - Prob. 61QAPCh. 18 - . What are some important uses of electrolysis?Ch. 18 - . Although aluminum is one of the most abundant...Ch. 18 - . The “Chemistry in Focus” segment Water-Powered...Ch. 18 - Prob. 65APCh. 18 - Prob. 66APCh. 18 - Prob. 67APCh. 18 - Prob. 68APCh. 18 - Prob. 69APCh. 18 - Prob. 70APCh. 18 - Prob. 71APCh. 18 - Prob. 72APCh. 18 - Prob. 73APCh. 18 - . To obtain useful electrical energy from an...Ch. 18 - Prob. 75APCh. 18 - Prob. 76APCh. 18 - Prob. 77APCh. 18 - Prob. 78APCh. 18 - . The “pressure” on electrons to flow from one...Ch. 18 - Prob. 80APCh. 18 - Prob. 81APCh. 18 - Prob. 82APCh. 18 - Prob. 83APCh. 18 - . For each of the following unbalanced...Ch. 18 - Prob. 85APCh. 18 - Prob. 86APCh. 18 - Prob. 87APCh. 18 - . Balance each of the following...Ch. 18 - . Balance each of the following...Ch. 18 - . For each of the following oxidation-reduction...Ch. 18 - . For each of the following oxidation-reduction...Ch. 18 - . Assign oxidation sates to all of the atoms in...Ch. 18 - . Assign oxidation states to all of the atoms in...Ch. 18 - Prob. 94APCh. 18 - Prob. 95APCh. 18 - . Assign oxidation states to all of the atoms in...Ch. 18 - Prob. 97APCh. 18 - . In each of the following reactions, identify...Ch. 18 - . Balance each of the following half-reactions....Ch. 18 - Prob. 100APCh. 18 - Prob. 101APCh. 18 - Prob. 102APCh. 18 - . Consider the oxidation—reduction reaction...Ch. 18 - Prob. 104APCh. 18 - Prob. 105CP
Knowledge Booster
Background pattern image
Chemistry
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
Chemistry
Chemistry
ISBN:9781133611097
Author:Steven S. Zumdahl
Publisher:Cengage Learning
Text book image
Chemistry & Chemical Reactivity
Chemistry
ISBN:9781337399074
Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel
Publisher:Cengage Learning
Text book image
Chemistry & Chemical Reactivity
Chemistry
ISBN:9781133949640
Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel
Publisher:Cengage Learning
Text book image
Chemistry: The Molecular Science
Chemistry
ISBN:9781285199047
Author:John W. Moore, Conrad L. Stanitski
Publisher:Cengage Learning
Text book image
Chemistry: Principles and Practice
Chemistry
ISBN:9780534420123
Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer
Publisher:Cengage Learning
Text book image
Chemistry by OpenStax (2015-05-04)
Chemistry
ISBN:9781938168390
Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser
Publisher:OpenStax
Balancing Redox Reactions in Acidic and Basic Conditions; Author: Professor Dave Explains;https://www.youtube.com/watch?v=N6ivvu6xlog;License: Standard YouTube License, CC-BY