CHM 2046C Name: ________________

Module 14 Paper and Pencil Homework Packet

Module Fourteen: Electrochemistry Chapter 17	Possible	Actual
Module 17 REDOX Review Chapter 4
A. M-8G Review: Rewrite Equations Ionically Section 4.3 (1 point each) (Balance)sample test	10	Answers
A1. M-8G Review: Rewrite Equations Ionically Section 4.3 (1 point each) Acid Media	20	Answers
A2. M-8G Review: Rewrite Equations Ionically Section 4.3 (1 point each) Basic Media	20	Answers
B. M-8H Review: Balancing REDOX Equations Sample test Item	10	Answers
B1. M-8H Review: Balancing REDOX Equations Sections 4.6, 4.7, 4.9, 4.10 (2 points each)
B1 Acid Media REDOX	20	ANSWERS
B2 Basic Media REDOX	20	Answers
Advanced Homework #1	10
Advanced Homework #2	10
Mother, Father, Son, Daughter, Mother-in-Law	Bonus
Module 17 REDOX Homework Total	120

Module 17: Part A Rewriting Equations Ionically (Balance) 10 points

Rewrite the following (unbalanced) equations ionically, cancel spectator ions and then balance the net ionic reactions.

Show as ions: soluble salts and strong acids; leave as molecules/formula units insoluble salts, weak acids, covalent molecules.

Strong acids are: Perchloric Acid; Hydrochloric Acid; Nitric Acid; Sulfuric Acid; Hydrobromic Acid; Hydroiodic Acid

1. KOH (aq) + HNO₃(aq) à KNO₃(aq) + HOH(l)

2. CuSO₄ (aq) + Na₂CO₃ (aq) à CuCO₃ (s) + Na₂SO₄ (aq)

3. NaOH (aq) + NH₄NO₃ (aq) à NaNO₃ (aq) + NH₃ (g) + HOH (l)

4. BaBr₂ (aq) + ZnSO₄ (aq) à BaSO₄ (s) + ZnBr₂ (aq)

5. Cr(OH)₂ (s) + HCl (aq) à

Part A1: Rewrite Equations Ionically (Section 4.3) Acid Media

Acid Media-20 Points (Do Not Balance)

REDOX Equations: Writing Net Ionic Reactions
Write net unbalanced ionic reactions for 20 of the following as a post lab report due REDOX Day or the week after as a post lab report:
The following Unbalanced Acid Media REDOX equations need to be re-written ionically Unbalanced.

Rewrite the following Unbalanced chemical equations ionically in total ionic form (without balancing), then cancel spectators for the net ionic equation. Do not forget to place charges on the ions and no charge on the molecules/formula units. This is Step#1 in REDOX balancing so the equations can not be balanced first as shown in the book (and as on the test item M-8G.)

Rewrite as ions electrolytes such as soluble salts, strong acids, and strong bases.

(a) Some strong acids are hydrochloric acid, nitric acid, sulfuric acid, perchloric acid, hydrobromic acid and hydroiodic acid.

(b) Strong bases include KOH and NaOH and any soluble hydroxide.

Redox Equations: Writing Net Ionic Reactions: Acid Media

Write net ionic reactions for all 20 of the following as a post lab report due the day of REDOX lab:

1. Zn (s) + HNO₃ (aq) à Zn(NO₃)₂ (aq) + NH₄NO₃ (aq) + H₂O (l)

2. KMnO₄(aq) + K₂C₂O₄(aq) + HCl(aq) à MnCl₂(aq) + CO₂(g) + KCl(aq) + H₂O(l)

3. K₂Cr₂O₇(aq) + HCl (aq) à CrCl₃(aq) + Cl₂ (g) + KCl (aq) + H₂O (l)

4. Cu (s) + HNO₃ (aq) à Cu(NO₃)₂ (aq) + NO₂ (g) + H₂O (l)

5. Cu (s) + HNO₃ (aq) à Cu(NO₃)₂ (aq) + NO₂ (g) + H₂O (l)

6. KI (aq) + HNO₃(aq) à NO (g) + I₂ (s) + KNO₃ (aq) + H₂O (l)

7. K₂Cr₂O₇(aq) + C₂H₅OH(aq) + HCl(aq) à CrCl₃(aq) + HC₂H₃O₂(aq)+ KCl(aq) + H₂O(l)

8. CH₂O (l) + H₂SO₄ (aq) à H₂S (g) + CO₂ (g) + H₂O (l)

9. Zn (s) + HNO₃(aq) à N₂ (g) + Zn(NO₃)₂ (aq) + H₂O

10. Zn (s) + HNO₃(aq) à N₂O (g) + Zn(NO₃)₂ (aq) + H₂O (l)

11. PbO₂ (s) + MnO (s) + HNO₃(aq) à HMnO₄(aq) + Pb(NO₃)₂ (aq) + H₂O (l)

12. MnSO₄(aq) + K₂S₂O₈(aq) +H₂Oà H₂SO₄(aq) + MnO₂(s)+K₂SO₄(aq)

13. CdS (aq) + I₂ (aq) + H₂SO₄ (aq) à CdSO₄ (aq) + HI (aq) + S (s)

14. KI (aq) + H₂SO₄ (aq) à K₂SO₄ (aq) + H₂S(aq) + I₂(aq) + H₂O (l)

15. K₂MnO₄(aq) +H₂SO₄ (aq) à KMnO₄(aq)+MnO₂+ K₂SO₄ (aq) + H₂O

16. H₂O₂ + KMnO₄(aq) + HCl (aq) à MnCl₂(aq) + KCl(aq) + O₂ + H₂O

17. FeS + KNO₃(aq) + H₂SO₄(aq) à NO + Fe(NO₃)₂(aq) + K₂SO₄(aq)+ KNO₃(aq) + H₂O

18. As₂S₅ + KNO₃(aq) + HNO₃(aq) à NO₂ + H₃AsO₄(aq) + KHSO₄(aq) + H₂O

19. KMnO₄ +H₂S+HClà MnCl₂ +S+ KCl + H₂O

20. KMnO₄ +KNO₂+HNO₃à MnO₂ +KNO₃+ H₂O

REDOX Challenge Contest: Basic Media REDOX Equations

Part A2: Rewrite Equations Ionically (Section 4.3) Basic Media 20 points

21: Bi₂O₃(s) + NaOH(aq)+ NaClO(aq) à NaBiO₃(aq) + NaCl(aq) + H₂O(l)

22: Zn(s) + VO₂NO₃(aq) + H₂O(l) + KNO₃(aq) à Zn(NO₃)₂(aq)+ VO(NO₃)₂(aq)+ KOH(aq)

23: V(OH)₄Cl(aq)+ SnCl₂(aq)+ KCl(aq) à VOCl₂(aq)+ SnCl₄(aq)+ KOH(aq)+ H₂O(l)

24: I₂(s) + KClO₃(aq) + KOH(aq) à KIO₃(aq) + KCl(aq) + H₂O(l)

25: Br₂(l) + SO₂(g) + KOH(aq) à KBr(aq) + K₂ SO₄ (aq) + H₂O(l)

26: Cr(OH)₄Cl(aq) + NaClO(aq)+ NaOH (aq) à Na₂CrO₄(aq) + NaCl(aq) + H₂O(l)

27: Zn(s) + NaNO₃(aq) + NaOH(aq) + H₂O(l) à Na₂ZnO₂(aq)+ NH₃(g)

28: KMnO₄ (aq) + K₂C₂O₄(aq) + KOH (aq)à MnO₂(s) + K₂CO₃ (aq) + H₂O(l)

29: Zn(s) + NaNO₃(aq) + NaOH(aq à Na₂[Zn(OH)₄] (aq) + NH₃(g) + H₂O(l)

30: H₂O₂(l) + Cl₂O₇(l)+ NaOH(aq) à O₂(g)+ NaClO₂ (aq) + H₂O(l)

31: KMnO₄(aq) + K₂C₂O₄ (aq) + KOH(aq) à MnO₂(s) + K₂CO₃ (aq) + H₂O(l)

32: KMnO₄ (aq) + KIO (aq) + H₂O(l) à MnO₂(s) + KIO₄(aq) + KOH(aq)

33:K₂C₄H₄O₆(aq)+ KClO₃(aq) + KOH(aq) à K₂CO₃(aq) + KCl (aq) + H₂O(l)

34: KMnO₄(aq) + KCN(aq) + H₂O(l)à MnO₂(s) + KCNO (aq) + KOH(aq)

35: Na₂S(aq) + I₂(s) + NaOH (aq) à Na₂SO₄ (aq) + NaI(aq) + H₂O (l)

36: Cr(OH)₃(s) + Cl₂(g) + NaOH (aq) à NaCl (aq) + Na₂CrO₄(aq) + H₂O(l)

37. Fe(OH)₂(s) + O₂(g) + H₂O(l) à Fe(OH)₃(s)

38. K₃Fe(CN)₆(aq) + Cr₂O₃(s) + KOH (aq à K₄Fe(CN)₆ (aq) + K₂CrO₄ (aq) + H₂O(l)

39: NaBH₄(aq) + NaClO₃(aq à NaH₂BO₃(aq) + NaCl(aq) + H₂O(l)

40. NaAlH₄(aq) + H₂CO₃(aq) + NaCl(aq) + H₂O(l) à AlCl₃(aq) + CH₃OH(l) + NaOH(aq)

Module 14 Part B: Redox Equations Sample Test Item 10 points

Balance the following redox equations written in net ionic form:

Acid Media: 5 points

1. C₂O₄ ^2- (aq) + MnO₄ ^1- (aq) + H ¹⁺ (aq) → Mn ²⁺ (aq) + CO₂ (g) + HOH (l)

half equation:

Basic Media 5 points

2. Bi₂O₃ (s) + OH ^1- (aq) + OCl ^1- (aq) → BiO₃ ^1- (aq) + Cl ^1- (aq) + HOH (l)

half equation:

CHM 2046C REDOX Challenge Contest Pre/Post Lab Report

Write and balance the 10 Acid Media, 8 Basic Media Redox, and 2 ‘Neutral’ Equations. Show the coefficients for these 20 reactions on this page, but neatly show all work for each equation either in your lab manual or on separate paper. (No more than two equations per side of page) Attach this work to this page and submit either before the Contest begins or one week after the Contest ends (directions from your instructor): (If you worked one of the below during the contest, just write the answer on this form and place *completed in contest

Current Reference: McMurry Chapter 4, Sections 4.3, 4.6, 4.7, 4.10

Ion-Electron Method or Half Equation Method (McMurry 4.10)

Acid Media: ((Select 3 of the 7 Net Ionic Equations)

Zn + NO₃ ^1- + H ¹⁺ à Zn ²⁺ + NH₄ ¹⁺ + H₂O

MnO₄ ^1- + C₂O₄ ^{2- +} H ¹⁺ à Mn ²⁺ + CO₂ + H₂O

Cr₂O₇ ^2- + C₂H₅OH + H ¹⁺ à Cr ³⁺ + HC₂H₃O₂ + H₂O

SO₄ ^2- + CH₂O + H ¹⁺ à H₂S + CO₂ + H₂O

FeS + NO₃ ^1- + H ¹⁺ à NO + Fe ²⁺ + SO₄ ^2- + H₂O

Cr₂O₇ ^2- + Cl ^1- + H ¹⁺ à Cr ³⁺ + Cl₂ + H₂O

H₂O₂ + MnO₄ ^1- + H ¹⁺ à Mn ²⁺ + O₂ + H₂O

(

(Select 7 of the 8 Total Molecular Equations)

MnO + PbO₂ + HNO₃ ---> HMnO₄ + Pb(NO₃)₂ + H₂O

Na₂HAsO₄ + KBrO₃ + HCl ---> NaCl + KBr + H₃AsO₄

WO₃ + SnCl₂ + HCl ---> W₃O₄ + H₂SnCl₆ + H₂O

As₂S₅ + HNO₃ ----> H₃AsO₄ + NaHSO₄ + NO₂ + H₂O

CuS + HNO₃ ----> Cu(NO₃)₂ + S + NO + H₂O

Na₂C₂O₄ + KMnO₄ + H₂SO₄ ---> K₂SO₄ + Na₂SO₄ + MnSO₄ + CO₂ +H₂O

U(SO₄)₂ + KMnO₄ + H₂O ---> H₂SO₄ + K₂SO₄ + MnSO₄ + UO₂SO₄

CdS + I₂ HCl ---> CdCl₂ + HI + S

Basic Media (Work four of the five) Net Ionic Equations

Cr ³⁺ + ClO₃ ^1- + OH ^1- à CrO₄ ^{2- +} Cl ^1- + H₂O

Bi₂O₃ + OH ^1- + OCl ^1- à BiO₃ ^1- + Cl ^1- H₂O

Mn ^2- + Br₂ + OH ^1- à MnO₂ + Br ^1- + H₂O

Fe(OH)₂ + O₂ + H₂O à Fe ³⁺ + OH ^1-

MnO₄ ^1- + C₂O₄ ^2- + OH ^1-+ H₂O à MnO₂ + CO₃ ^2-

Work all four of the following: Total Molecular Equations

Zn + NaNO₃ + NaOH à Na₂ZnO₂ + NH₃ + H₂O

Ag + KCN^- + O₂ + H₂O à KAg(CN)₂ + KOH

CoCl₂ + Na₂O₂ + NaOH + H₂O ---> Co(OH)₃ + NaCl

K₃Fe(CN)₆ + Cr₂O₃ + KOH ---> K₄Fe(CN)₆ + K₂CrO₄ + H₂O

K₂C₄H₄O₆+ KClO₃ + KOH à K₂CO₃ + KCl + H₂O

AsO₂ ^1- + ClO ^1- à AsO₃ ^1- + Cl ^1- (basic solution)

‘Neutral’ Media (No H ¹⁺ or OH ^1- Ions Present)* * Actually Lewis Acids and Bases

The last two below are required, so give them a try!

Ca₃(PO₄)₂ (aq) + SiO₂ (s) + C (s) à CaSiO₃ (aq) + P₄ (s) + CO (g)

Cu(NH₃)₄Cl₂ + KCN + HOH(l) ---> NH₃(g) + NH₄Cl + K₂Cu(CN)₃ + KCNO + KCl

Homework for the Most Advanced Students #1:

(These Equations are part of the contest beyond Round 12)

Neutral Media:

(NH₄)₂MoO₄ + NH₄NO₃ + Na₃PO₄ à H₂O + (NH₄)₃[P(Mo₃O₁₀)₄] + NaNO₃ + NH₃

Net Ionic Reaction:

Half Equation:

Half Equation

Final Answer:

(NH₄)₂MoO₄ + NH₄NO₃ + Na₃PO₄ à H₂O + (NH₄)₃[P(Mo₃O₁₀)₄] + NaNO₃ + NH₃

Acid Media

CoCl₂ + KNO₂ + HC₂H₃O₂ ----> K₃Co(NO₂)₆ + NO + KC₂H₃O₂ + KCl + HOH

Net Ionic Reaction:

Half Equation:

Half Equation

Final Answer:

CoCl₂ + KNO₂ + HC₂H₃O₂ ----> K₃Co(NO₂)₆ + NO + KC₂H₃O₂ + KCl + HOH

Basic Media

CrI₃ + KOH + Cl₂ ----> K₂CrO₄ + KIO₄ + KCl + HOH

Net Ionic Reaction:

Half Equation:

Half Equation

Final Answer:

CrI₃ + KOH + Cl₂ ----> K₂CrO₄ + KIO₄ + KCl + HOH

Homework for the Most Advanced Students #2:

(Acid Media):

K₄Fe(CN)₆ + H₂SO₄ + KMnO₄ à MnSO₄ + Fe₂(SO₄)₃ + K₂SO₄ + KNO₃ + CO₂ + H₂O

Net ionic Reaction:

Half Equation:

Half Equation

Final Answer:

K₄Fe(CN)₆ + H₂SO₄ + KMnO₄ à MnSO₄ + Fe₂(SO₄)₃ + K₂SO₄ + KNO₃ + CO₂ + H₂O

(Basic Media):

Bi(NO₃)₃+ Al + NaOH à Bi + NH₃ + NaAlO₂

Net ionic Reaction:

Half Equation:

Half Equation

Final Answer:

Bi(NO₃)₃+ Al + NaOH à Bi + NH₃ + NaAlO₂

(Neutral Media):

P₂I₄ + P₄ + H₂O à PH₄I + H₃PO₄

Net ionic Reaction:

Half Equation:

Half Equation

Final Answer:

P₂I₄ + P₄ + H₂O à PH₄I + H₃PO₄

(Acid Media):

As₂S₅ + KNO₃ + HNO₃ à NO₂ + H₃AsO₄ + KHSO₄ + H₂O

Net ionic Reaction:

Half Equation:

Half Equation

Final Answer:

As₂S₅ + KNO₃ + HNO₃ à NO₂ + H₃AsO₄ + KHSO₄ + H₂O

Bonus Exercises

The following are deemed the hardest REDOX Equations to balance in the world:

Daughter of All REDOX Equations:
HIO₃ + FeI₂ + HCl ---> FeCl₃ + ICl + HOH
(A hint: the coefficients of the daughter equation will add up to 66)

Son of All REDOX Equations:
CuSCN + KIO₃ + HCl ---> CuSO₄ + KCi + HCN + ICl + HOH

Father of All REDOX Equations:
NH₄ClO₄ + Al ---> HCl + Cl₂ + NO + AL₂O₃ + HOH

Mother of All REDOX Equations:
[Cr(N₂H₄CO)₆]₄[Cr(CN)₆]₃ + KMnO₄ + H₂SO₄ --->

K₂Cr₂O₇ + MnSO₄ + CO₂ + KNO₃ + K₂SO₄ + HOH

Equation The Ultimate: Acid Media-Total Molecular Form:

The Ultimate Equation:

H₂ + Ca(CN)₂ + NaAlF₄ + FeSO₄ + MgSiO₃ + KI + H₃PO₄ + PbCrO₄ + BrCl +

CF₂Cl₂ + SO₂

PbBr₂ + CrCl₃ + MgCO₃ + KAl(OH)₄ + Fe(SCN)₃ + PI₃ + NaSiO₃ + CaF₂

+ H₂O

Final Answer:

119 H₂ + 18 Ca(CN)₂ + 6 NaAlF₄ + 12 FeSO₄ + 6 MgSiO₃ + 6 KI + 2 H₃PO₄ +

12 PbCrO₄ + 24 BrCl + 6 CF₂Cl₂ + 24 SO₂

12 PbBr₂ + 12 CrCl₃ + 6 MgCO₃ + 6 KAl(OH)₄ + 12 Fe(SCN)₃ + 2 PI₃ +

6 NaSiO₃ + 18 CaF₂ + 110 H₂O

Alternate Answer:

88 H₂ + 15 Ca(CN)₂ + 6 NaAlF₄+ 10 FeSO₄ + 3 MgSiO₃ + 6 KI + 2 H₃PO₄

+ 6 PbCrO₄ + 12 BrCl + 3 CF₂Cl₂ + 20 SO₂

6 PbBr₂ + 6 CrCl₃ + 3 MgCO₃ + 6 KAl(OH)₄ + 10 Fe(SCN)₃ + 2 PI₃ + 3 Na₂SiO3 + 15 CaF₂ + 79 H₂O

22: Zn(s) + VO2NO3(aq) + H2O(l) + KNO3(aq) à Zn(NO3)2(aq) + VO(NO3)2(aq) + KOH(aq)

Current Reference: McMurry Chapter 4, Sections 4.3, 4.6, 4.7, 4.10

Ion-Electron Method or Half Equation Method (McMurry 4.10)

Zn + NO3 1- + H 1+ à Zn 2+ + NH4 1+ + H2O

Cr 3+ + ClO3 1- + OH 1- à CrO4 2- + Cl 1- + H2O

Daughter of All REDOX Equations: HIO3 + FeI2 + HCl ---> FeCl3 + ICl + HOH (A hint: the coefficients of the daughter equation will add up to 66)

Son of All REDOX Equations: CuSCN + KIO3 + HCl ---> CuSO4 + KCi + HCN + ICl + HOH

Father of All REDOX Equations: NH4ClO4 + Al ---> HCl + Cl2 + NO + AL2O3 + HOH

Mother of All REDOX Equations: [Cr(N2H4CO)6]4[Cr(CN)6]3 + KMnO4 + H2SO4 --->

K2Cr2O7 + MnSO4 + CO2 + KNO3 + K2SO4 + HOH

22: Zn(s) + VO₂NO₃(aq) + H₂O(l) + KNO₃(aq) à Zn(NO₃)₂(aq)+ VO(NO₃)₂(aq)+ KOH(aq)

Zn + NO₃ ^1- + H ¹⁺ à Zn ²⁺ + NH₄ ¹⁺ + H₂O

Cr ³⁺ + ClO₃ ^1- + OH ^1- à CrO₄ ^{2- +} Cl ^1- + H₂O

Daughter of All REDOX Equations:
HIO₃ + FeI₂ + HCl ---> FeCl₃ + ICl + HOH
(A hint: the coefficients of the daughter equation will add up to 66)

Son of All REDOX Equations:
CuSCN + KIO₃ + HCl ---> CuSO₄ + KCi + HCN + ICl + HOH

Father of All REDOX Equations:
NH₄ClO₄ + Al ---> HCl + Cl₂ + NO + AL₂O₃ + HOH

Mother of All REDOX Equations:
[Cr(N₂H₄CO)₆]₄[Cr(CN)₆]₃ + KMnO₄ + H₂SO₄ --->

K₂Cr₂O₇ + MnSO₄ + CO₂ + KNO₃ + K₂SO₄ + HOH