Concept explainers
(a)
Interpretation:
The given
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
The following rules must be followed in balancing redox reaction by half equation method:
- Initially, redox reaction is separated into two half equations; oxidation and reduction.
- Atoms other than hydrogen and oxygen are balanced first in the unbalanced half equations.
- Oxygen atoms are balanced by addition of water on either side of the reaction.
- Hydrogen ion/s is added to balance the hydrogen atom.
- Electrons are added to balance the charge.
- Half reactions are added to get the net total equation.
- 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 101AP
Explanation of Solution
The given reaction is as follows:
The above reaction can be separated into two half reactions as follows:
And,
In reaction (1), give coefficient 2 to
Add two electrons to the right to balance the charge thus,
In reaction (2), add 4 water molecules to right side of the reaction to balance the number of oxygen atom,
Now, add 8 hydrogen ions to the left, to balance the hydrogen atoms.
Last step is to balance the charge, the net charge on left side is + 7 and that on right side is + 2 thus, add 5 electrons to the left to balance the charge,
To get the overall reaction, add reaction (3) and (4)
Thus, the balance oxidation-reduction reaction is as follows:
(b)
Interpretation:
The given oxidation-reduction reaction should be balanced
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:
- Initially, redox reaction is separated into two half equations; oxidation and reduction.
- Atoms other than hydrogen and oxygen are balanced first in the unbalanced half equations.
- Oxygen atoms are balanced by addition of water on either side of the reaction.
- Hydrogen ion/s is added to balance the hydrogen atom.
- Electrons are added to balance the charge.
- Half reactions are added to get the net total equation.
- 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 101AP
Explanation of Solution
The given reaction is as follows:
The above reaction can be separated into two half reactions as follows:
And,
In reaction (1), give coefficient 2 to
Add 4 electrons to the left to balance the charge thus,
In reaction (2), give coefficient 2 to
Add 7 water molecules to left side of the reaction to balance the number of oxygen atom,
Balance the hydrogen atoms to add 14 hydrogen ions to the right:
Last step is to balance the charge, the net charge on left side is + 6 and that on right side is + 12 thus, add 6 electrons to the right to balance the charge,
To get the overall reaction, add reaction (3) and (4)
Thus, the balance oxidation-reduction reaction is as follows:
(c)
Interpretation:
The given oxidation-reduction reaction should be balanced
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:
- Initially, redox reaction is separated into two half equations; oxidation and reduction.
- Atoms other than hydrogen and oxygen are balanced first in the unbalanced half equations.
- Oxygen atoms are balanced by addition of water on either side of the reaction.
- Hydrogen ion/s is added to balance the hydrogen atom.
- Electrons are added to balance the charge.
- Half reactions are added to get the net total equation.
- 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 101AP
Explanation of Solution
The given reaction is as follows:
The above reaction can be separated into two half reactions as follows:
And,
In reaction (1), add 3 water molecules on right side to balance the number of oxygen atoms,
To balance the hydrogen atom, add 6 hydrogen ions to the left thus,
Now, balance the charge by adding 2 electrons to the left
In reaction (2), add 4 water molecules on left to balance the oxygen atoms.
Hydrogen atoms can be balanced by adding 8 hydrogen ions on the right:
Last step is to balance the charge, add 5 electrons to the right:
To get the overall reaction, add reaction (3) and (4)
Thus, the balance oxidation-reduction reaction is as follows:
Want to see more full solutions like this?
Chapter 18 Solutions
Introductory Chemistry: A Foundation, Hybrid Edition
- Gold can be dissolved from gold-bearing rock by treating the rock with sodium cyanide in the presence of oxygen. 4 Au(s) + 8 NaCN(aq) + O2(g) + 2 H2O() 4 NaAu(CN)2(aq) + 4 NaOH(aq) (a) Name the oxidizing and reducing agents in this reaction. What has been oxidized, and what has been reduced? (b) If you have exactly one metric ton (1 metric ton = 1000 kg) of gold-bearing rock, what volume of 0.075 M NaCN, in liters, do you need to extract the gold if the rock is 0.019% gold?arrow_forwardFour metals, A, B, C, and D, exhibit the following properties: (a) Only A and C react with 1.0 M hydrochloric acid to give H2(g). (b) When C is added to solutions of the ions of the other metals, metallic B, D, and A are formed. (c) Metal D reduces Bn+ to give metallic B and Dn+. Based on this information, arrange the four metals in order of increasing ability to act as reducing agents.arrow_forwardBalance each of the following oxidationreduction reactions by using the oxidation states method. a.Cl2(g) + Al(s) Al3+(aq) + Cl(aq) b.O2(g) + H2O(l) + Pb(s) Pb(OH)2(s) c.H+(aq)+MnO4(aq)+Fe2+(aq)Mn2+(aq)+Fe3+(aq)+H2O(l)arrow_forward
- Balance each of the following oxidationreduction reactions by using the oxidation states method. a. C2H6(g) + O2(g) CO2(g) + H2O(g) b. Mg(s) + HCl(aq) Mg2+(aq) + Cl(aq) + H2(g) c. Co3+ (aq) + Ni(s) Co2+(aq) + Ni2+(aq) d. Zn(s) + H2SO4(aq) ZnSO4(aq) + H2(g)arrow_forwardThe blood alcohol (C2H5OH) level can be determined by titrating a sample of blood plasma with an acidic potassium di-chromate solution, resulting in the production of Cr3+ (aq) and carbon dioxide. The reaction can be monitored because the dichromate ion (Cr2O72) is orange in solution, and the Cr3+ ion is green. The balanced equations is 16H+(aq) + 2Cr2O72(aq) + C2H5OH(aq) 4Cr4+(aq) + 2CO2(g) + 11H2O(l) This reaction is an oxidationreduction reaction. What species is reduced, and what species is oxidized? How many electrons are transferred in the balanced equation above?arrow_forwardWhich of the following ions is most easily reduced? (a) Cu2+(aq) (b) Zn2+(aq) (c) Fe2+(aq) (d) Ag+(aq) (e) Al3+(aq)arrow_forward
- The Toliens test for the presence of reducing sugars (say, in a urine sample) involves treating the sample with silver ions in aqueous ammonia. The result is the formation of a silver mirror within the reaction vessel if a reducing sugar is present. Using glucose, C6H12O6, to illustrate this test, the oxidation-reduction reaction occurring is C6H12O6 (aq) + 2 Ag+(aq) + 2OH(aq) C6H12O7(aq) + 2 Ag(s) + H2O() What has been oxidized, and what has been reduced? What is the oxidizing agent, and what is the reducing agent? Tolien's test. The reaction of silver ions with a sugar such as glucose produces metallic silver. (a) The set-up for the reaction. (b) The silvered test tubearrow_forwardChromium has been investigated as a coating for steel cans. The thickness of the chromium film is determined by dissolving a sample of a can in acid and oxidizing the resulting Cr3+ to Cr2O72 with the peroxydisulfate ion: S2O82(aq) + Cr3+(aq) + H2O(l) Cr2O72(aq) + SO42(aq) + H+(aq) (Unbalanced) After removal of unreacted S2O82 an excess of ferrous ammonium sulfate [Fe(NH4)2(SO4)26H2O] is added, reacting with Cr2O72 produced from the first reaction. The unreacted Fe2+ from the excess ferrous ammonium sulfate is titrated with a separate K2Cr2O7 solution. The reaction is: H+(aq) + Fe2+(aq) + Cr2O72(aq) Fe3+(aq) + Cr3+(aq) + H2O(l) (Unbalanced) a. Write balanced chemical equations for the two reactions. b. In one analysis, a 40.0-cm2 sample of a chromium-plated can was treated according to this procedure. After dissolution and removal of excess S2O82, 3.000 g of Fe(NH4)2(SO4)26H2O was added. It took 8.58 mL of 0.0520 M K2Cr2O7 solution to completely react with the excess Fe2+. Calculate the thickness of the chromium film on the can. (The density of chromium is 7.19 g/cm3)arrow_forwardBalance each of the following oxidationreduction reactions by using the oxidation states method. a.C2H4(g) + O2(g) CO3(g) + H2O(g) b. Mg(s) + HCl(aq) Mg2+(aq) + Cl(aq) + H2(g) c.Co3+(aq) + Ni(s) Co2+(aq) + Ni2+(aq) d.Zn(s) + H2SO4(aq) ZnSo4(aq) + H2(g)arrow_forward
- Chemistry: An Atoms First ApproachChemistryISBN:9781305079243Author:Steven S. Zumdahl, Susan A. ZumdahlPublisher:Cengage LearningChemistry & Chemical ReactivityChemistryISBN:9781337399074Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage Learning
- Chemistry & Chemical ReactivityChemistryISBN:9781133949640Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage LearningChemistryChemistryISBN:9781305957404Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCostePublisher:Cengage Learning