CHAPTER 12. Practice exercises

Size: px
Start display at page:

Download "CHAPTER 12. Practice exercises"

Transcription

1 CHAPTER 12 Practice exercises Al(s) + 3Cl 2 (g) 2AlCl 3 (aq) Aluminium is oxidised and is therefore the reducing agent. Chlorine is reduced and is therefore the oxidising agent First the oxidation numbers of all atoms must be determined. Cl 2 + 2NaClO 2 2ClO 2 + 2NaCl Reactants: Products: Cl 0 Cl +4 O 2 Na +1 Cl +3 Na +1 O 2 Cl 1 The oxidation numbers for O and Na do not change. However, the oxidation numbers for chlorine atoms can change. There is no simple way of working out which chlorines are reduced and which are oxidised in this reaction. One possibility is that the Cl in Cl 2 ends up as the Cl in NaCl and the Cl in NaClO 2 ends up as the Cl in ClO 2. In this case Cl 2 is reduced and is the oxidising agent and NaClO 2 is oxidised and is the reducing agent Sn H + + 2TcO 4 2Tc H 2 O + 3Sn anode: Mg(s) Mg 2+ (aq) + 2e cathode: Fe 2+ (aq) + 2e Fe(s) cell notation: Mg(s) Mg 2+ (aq) Fe 2+ (aq) Fe(s)

2 12.9 2Cl + Br 2 Cl Br G o = kj Cell potential = 1.04 V Sn(s) Review questions 12.1 (a) Oxidation is the loss of one or more electrons. Reduction is the gain of one or more electrons. (b) The oxidation number decreases in a reduction and increases in an oxidation The number of electrons involved in both the reduction and the oxidation must be the same; only those electrons that come from the reductant and go to the oxidant are involved. No electrons from external or uninvolved sources are involved and there cannot be any electrons left unaccounted for at the end. An oxidising agent is the species that is reduced or gains electrons in an oxidation/reduction reaction. A reducing agent is the species that is oxidised or loses electrons in an oxidation/ reduction reaction Nitrogen is reduced. This change in oxidation number requires that nitrogen gains five electrons These equations are not balanced since the charge is different on each side of the arrow. Balancing gives: (a) 2Ag + Fe 2+ 2Ag + + Fe (b) 2Cr Zn 2Cr + 3Zn (a) 2Ag 2Ag + + 2e is oxidation Fe e Fe is reduction (b) 3Zn 3Zn e is oxidation 2Cr e 2Cr is reduction A galvanic cell is one in which a spontaneous redox reaction occurs producing electricity. A half-cell consists of either the cathode or the anode, together with the accompanying electrolyte.

3 12.13 These must be kept separate otherwise Ag + ions are reduced directly by Cu metal and no external current is produced Electrolytic conduction is the flow of positive and negative ions. Metallic conduction is the flow of electrons Magnesium metal is oxidised at the anode and copper ions are reduced at the cathode to copper metal: Mg(s) + Cu 2+ (aq) Mg 2+ (aq) + Cu(s). The anode half-cell is a magnesium wire dipping into a solution of Mg 2+ ions and the cathode half-cell is a copper wire dipping into a solution of Cu 2+ ions. Additionally a salt bridge connects the two half-cell compartments Silver is reduced because it has a more positive E o than iron. The standard cell notation is Ag(s) Ag + (aq) Fe 3+ (aq) Fe(s) A potential is the measure of the electron flow through an external circuit. The unit of potential is the volt The cell potential for the anode half-cell reaction is subtracted from the cell potential for the cathode half-reaction: E o cell = E o substance reduced E o substance oxidised E o cell = E o reduction E o oxidation No, emf measurements require a complete circuit for current flow and there must be two half-cells connected with a salt bridge.

4 12.27 A positive reduction potential indicates that the system is more easily reduced than the hydrogen ion. Conversely, a negative reduction potential indicates that the system comprising the half-cell is less easily reduced than the hydrogen ion The negative terminal of the voltmeter must be connected to the anode in order to obtain correct readings of the voltage that is generated by the cell The strongest oxidising agent is H + (aq) The half-reactions at the top of table 12.1 have the greatest tendency to occur as a reduction, the half-reactions at the bottom of the table have the greatest tendency to occur as an oxidation G o = nf E o cell The Nernst equation: RT E cell = E o cell nf R = J mol 1 K 1 T = 25 C = 298 K F = C mol 1 RT F ln Q = J C 1 In x = log x J E cell = E o cell 1 1n Q n C J E cell = E o cell 1 log Q n C If the system is at equilibrium, Q = K c and E cell = J 0 = E o cell log K 1 n C c J E o cell = log K 1 n C c

5 12.39 We begin by separating the reaction into its two half-reactions in order to obtain the value of n: Pb(s) + SO 4 2 (aq) PbSO 4 (s) + 2e PbO 2 (s) + 4H 4 (aq) + SO 4 2 (aq) + 2e PbSO 4 (s) + 2H 2 O( l ) Thus, n = 2: E cell = E o cell n log Q E cell = log H SO Electrons are negatively charged and move towards the electrode where reduction occurs. This is the cathode oxidation: 2H 2 O(l) 4H + (aq) + 4e + O 2 (g) reduction: 2H 2 O(l) + 2e H 2 (g) + 2OH (aq) One Faraday (F) is equivalent to one mole of electrons. Also, one Faraday is equal to Coulombs and a Coulomb is equivalent to an Ampere second: 1 F = C and 1 C = 1 A s Copper has a larger atomic mass than iron and therefore, the copper deposits a greater mass of metal. Both metals are in the same +2 oxidation state anode: PbSO 4 (s) + 2H 2 O(l) 2e + PbO 2 (s) + 4H + (aq) + SO 2 4 (aq) cathode: PbSO 4 (s) + 2e Pb(s) + SO 2 4 (aq) anode: Zn(s) + 2OH (aq) ZnO(s) + H 2 O(l) + 2e cathode: 2MnO 2 (s) + H 2 O(l) + 2e Mn 2 O 3 (s) + 2OH (aq) The hydrogen is absorbed by the alloy, Mg 2 Ni. The electrolyte is KOH The electrode materials in a typical lithium cell are graphite and cobalt oxide. When the cell is charged, Li + ions migrate to the graphite. When the cell discharges, the Li + ions migrate back to the cobalt oxide and the electrons move through the external circuit to maintain charge balance.

6 12.57 Rust is iron oxide hydroxide, FeO(OH), that is formed by the reaction of iron with oxygen in the presence of water. Rusting of iron is a three-step process. Firstly, iron hydroxide, Fe(OH) 2, is formed by the reaction: 2Fe + O 2 + 2H 2 O 2Fe(OH) 2 Fe(OH) 2 is then oxidised to Fe(OH) 3 : 4Fe(OH) 2 + O 2 + 2H 2 O 4Fe(OH) 3 And finally, FeO(OH) is formed by dehydration of Fe(OH) 3 : Fe(OH) 3 FeO(OH) + H 2 O Passivation is a phenomenon shown by some elements, for example, aluminium and zinc, which are stable to air, although their reduction potentials are strongly negative. These metals form an impermeable layer of metal oxide that is stable over a wide ph range, which covers a corrosive metal and protects it from oxidation. Review problems (a) substance reduced (and oxidising agent): HNO 3 substance oxidised (and reducing agent): H 3 AsO 3 (b) substance reduced (and oxidising agent): HOCl substance oxidised (and reducing agent): NaI (c) substance reduced (and oxidising agent): KMnO 4 substance oxidised (and reducing agent): H 2 C 2 O 4 (d) substance reduced (and oxidising agent): H 2 SO 4 substance oxidised (and reducing agent): Al (e) substance reduced (and oxidising agent): H 2 SO 4 substance oxidised (and reducing agent): Cu (f) substance reduced (and oxidising agent): HNO 3 substance oxidised (and reducing agent): SO 2 (g) substance reduced (and oxidising agent): H 2 SO 4 substance oxidised (and reducing agent): Zn (h) substance reduced (and oxidising agent): HNO 3 substance oxidised (and reducing agent): I 2 (i) substance reduced (and oxidising agent): NaClO 4 Substance oxidised (and reducing agent): HCl (a) Na +1, H +1, P +5, O 2 (b) MnO 4 does not exist, however, for empirical MnO 4, Mn +8, O 2 (c) Na +1, S = + 2.5, O 2 (d) Cl + 3, F 1 (e) O 2, Cl +1 (f) Cl +3, O 2 (g) Cl + 5, O 2 (h) Cl +7, O 2 (i) Ca +2, V +5, O 2 (j) Sn +4, Cl 1 (k) Mn +6, O 2

7 (l) Mn +4, O 2 (m) Pb +2, S 2 (n) Ti +4, Cl 1 (o) Sr +2, I +5, O 2 (p) Cr +3, S 2 (q) F 1, O +0.5 (r) H +1, O 0, F 1 (s) Cl +4, O 2 (t) F 1, O In the forward reaction, Cl 2 undergoes disproportion. One chlorine atom is reduced to Cl and the other is oxidised to Cl + (in HOCl). In the reverse reaction, HOCl is the oxidising agent and Cl is the reducing agent (a) BiO 3 + 6H + + 2e Bi H 2 O 2 Reduction of BiO 3 (b) Pb H 2 O PbO 2 + 4H + + 2e Oxidation of Pb 2+ (c) NO H + + 8e NH H 2 O 2 Reduction of BiO 3 (d) 6H 2 O + Cl 2 2ClO H e Oxidation of Cl (a) 2S 2 O 2 3 S 4 O e OCl + 2H + + 2e Cl + H 2 O Net: OCl + 2S 2 O H + S 4 O Cl + H 2 O (b) (NO 3 + 2H + + e NO 2 + H 2 O) 2 Cu Cu e Net: 2NO 3 + Cu + 4H + 2NO 2 + Cu H 2 O (c) (d) (e) IO 3 + 6H + + 6e I + 3H 2 O (H 2 O + AsO 3 3 AsO H + + 2e ) 3 Net: IO 3 + 3AsO H + + 3H 2 O I + 3AsO H 2 O + 6H + 3AsO IO 3 I + 3AsO 4 3 SO H + + 2e SO 2 + 2H 2 O Zn Zn e Net: Zn + SO H + Zn 2+ + SO 2 + 2H 2 O NO H + + 8e NH H 2 O (Zn Zn e ) 4 Net: NO 3 + 4Zn + 10H + 4Zn 2+ + NH H 2 O (f) 2Cr H 2 O Cr 2 O H + + 6e (BiO 3 + 6H + + 2e Bi H 2 O) 3 Net: 2Cr BiO H + + 7H 2 O Cr 2 O H + + 3Bi H 2 O 2Cr BiO 3 + 4H + Cr 2 O Bi H 2 O

8 (g) I 2 + 6H 2 O 2IO H e (OCl + 2H + + 2e Cl + H 2 O) 5 Net: I 2 + 5OCl + H 2 O 2IO 3 + 5Cl + 2H + (h) (Mn H 2 O MnO 4 + 8H + + 5e ) 2 (BiO 3 + 6H + + 2e Bi H 2 O) x 5 2Mn BiO H + + 8H 2 O 2MnO 4 + 5Bi H H 2 O Net: 2Mn BiO H + 2MnO 4 + 5Bi H 2 O (i) (H 3 AsO 3 + H 2 O H 3 AsO 4 + 2H + + 2e ) 3 Cr 2 O H + + 6e 2Cr H 2 O Net: 3H 3 AsO 3 + Cr 2 O H 2 O + 14H + 3H 3 AsO 4 + 2Cr H + + 7H 2 O 3H 3 AsO 3 + Cr 2 O H + 3H 3 AsO 4 + 2Cr H 2 O (j) 2I I 2 + 2e HSO 4 + 3H + + 2e SO 2 + 2H 2 O Net: 2I + HSO 4 + 3H + I 2 + SO 2 + 2H 2 O (k) (Sn + 2H 2 O SnO 2 + 4H + + 4e ) 3 (ΝΟ 3 + 4H + + 3e NO + 2H 2 O) 4 Net: 3Sn + 4NO H + + 6H 2 O 3SnO H + + 4NO + 8H 2 O 3Sn + 4NO 3 + 4H + 3SnO 2 + 4NO + 2H 2 O (l) PbO 2 + 2Cl + 4H + + 2e PbCl 2 + 2H 2 O 2Cl Cl 2 + 2e Net: PbO 2 + 4Cl + 4H + PbCl 2 + Cl 2 + 2H 2 O (m) Ag Ag + + e NO 3 + 2H + + e ΝΟ 2 + Η 2 Ο Net: Ag + 2H + + NO 3 Ag + + NO 2 + H 2 O (n) (Fe 3+ + e Fe 2+ ) 4 2NH 3 OH + N 2 O + H 2 O + 6H + + 4e Net: 4Fe NH 3 OH + 4Fe 2+ + N 2 O +6H + +H 2 O (o) 2I I 2 + 2e (HNO 2 + H + + e NO + H 2 O) 2 Net: 2I + 2HNO 2 + 2H + I 2 + 2NO + 2H 2 O (p) C 2 O 4 2 2CO 2 + 2e (HNO 2 + H + + e NO + H 2 O) 2 Net: C 2 O HNO 2 + 2H + 2CO 2 + 2NO + 2H 2 O (q) (HNO 2 + H 2 O NO 3 + 3H + + 2e ) 5

9 (MnO 4 + 8H + + 5e Mn H 2 O) 2 Net: 5HNO 2 + 2MnO H + + 5H 2 O 5NO 3 + 2Mn H + + 8H 2 O 5HNO 2 + 2MnO 4 + H + 5NO 3 + 2Mn H 2 O (r) (H 3 PO 2 + 2H 2 O H 3 PO 4 + 4H + + 4e ) 3 (Cr 2 O H + + 6e 2Cr 3 + 7H 2 O) 2 Net: 3H 3 PO 2 + Cr 2 O H + + 6H 2 O 3H 3 PO 4 + 4Cr H 2 O + 12H + 3H 3 PO 2 + 2Cr 2 O H + 3H 3 PO 4 + 4Cr H 2 O (s) (VO H + + e VO 2+ + H 2 O) 2 Sn 2+ Sn e Net: 2VO Sn H + 2VO 2+ + Sn H 2 O (t) XeF 2 + 2e Xe + 2F 2Cl Cl 2 + 2e Net: XeF 2 + 2Cl Xe + Cl 2 + 2F (u) S 2 O H 2 O 2SO H + + 8e (OCl + 2H + + 2e Cl + H 2 O) 4 Net: S 2 O H 2 O + 4OCl 2SO H + + 4Cl O 3 + Br BrO Cu(s) Cu e H 2 SO 4 + 2H + + 2e SO 2 + 2H 2 O Cu + H 2 SO 4 + 2H + Cu 2+ + SO 2 + 2H 2 O Since Ru reduces Pt 2+, it is more reactive than Pt (Ru > Pt) Since Tl reduces Ru 2+, it is more reactive than Ru (Tl > Ru) Since Pu reduces Tl +, it is more reactive than Tl (Pu > Tl) Therefore the increasing ease of oxidation is: Pu > Tl> Ru > Pt Cd(s) + Pt 2+ (aq) Cd 2+ (aq) + Pt(s) (a) Fe(s) Fe 2+ (aq) Cd 2+ (aq) Cd(s) (b) Pt(s) Br 2 (aq), Br (aq) Cl 2 (g), Cl - (aq), Pt(s) (c) Ag(s) Ag + (aq) Au 3+ (aq) Au(s) (d) Pt(s) Fe 2+ (aq), Fe 3+ (aq) NO - 3 (aq), NO(g) Pt(s) (e) Ag(s) Ag + (aq) NiO 2 (s), Ni 2+ (aq) Pt(s) (f) Mg(s) Mg 2+ (aq) Cd 2+ (aq) Cd(s)

10 12.81 (a) E o cell = 0.88 V spontaneous (b) E o cell = 1.40 V not spontaneous (c) E o cell = 2.02 V spontaneous (d) E o cell = 0.29 V not spontaneous (e) E o cell = V spontaneous (f) E o cell = V spontaneous (g) E o cell = 0.37 V not spontaneous (a) BrO 3 (aq) + 6I (aq) + 6H + (aq) 3I 2 (s) + Br (aq) + 3H 2 O net reaction E o cell = 0.90 V (b) MnO 2 (s) + 4H + (aq) + Pb(s) + 2Cl (aq) Mn 2+ (aq) + 2H 2 O(l) + PbCl 2 (aq) net reaction E o cell = 1.5 V Br 2 (aq) + 2e 2Br (aq) E o cell = 1.07 V I 2 (s) + 2e 2I (aq) E o cell = 0.54 V Since the first of these has the larger reduction half-cell potential, it is reduction and the second is reversed as oxidation: Br 2 (aq) + 2I (aq) I 2 (s) + 2Br (aq) E o cell = E o reduction E o oxidation = 1.07 V (0.54 V) = 0.53 V (a) E o cell = 0.54 V (b) G o = kj (c) K c = anti-ln(210.3) = K c = anti-log ( 0.51) = E cell = V J K 1 mol K / C mol 1 ln 6 10 [ ] [ 0.001] 5 34 [ 0.01] [ 0.1] = V V ln ( ) = V V ( 23.03) = V ( 0.02 V) = V M (a) 2400 C, equivalent to moles of electrons (b) C, equivalent to moles of electrons (c) C, equivalent to moles of electrons

11 mol Cr 3+ would be reduced. Electrolysis would take 45 minutes g Cl hr L HCl or 40.2 ml HCl V = L or 78.4 ml (a) 2H 2 (O)(l) + 2e H 2 (g) + 2OH (aq) (b) Cu 2+ (aq) + 2e Cu(s) (c) Cu 2+ (aq) + 2e Cu(s) Additional exercises Increasing ease of oxidation: Cu Fe Pb Al. The second and fifth experiments are not required to establish this order (a) aluminium (b) zinc (c) magnesium g PbO 2 is required Standard reduction potential = V E cell = 0.30 V s

CHEMISTRY 13 Electrochemistry Supplementary Problems

CHEMISTRY 13 Electrochemistry Supplementary Problems 1. When the redox equation CHEMISTRY 13 Electrochemistry Supplementary Problems MnO 4 (aq) + H + (aq) + H 3 AsO 3 (aq) Mn 2+ (aq) + H 3 AsO 4 (aq) + H 2 O(l) is properly balanced, the coefficients will

More information

Electrochemistry. A. Na B. Ba C. S D. N E. Al. 2. What is the oxidation state of Xe in XeO 4? A +8 B +6 C +4 D +2 E 0

Electrochemistry. A. Na B. Ba C. S D. N E. Al. 2. What is the oxidation state of Xe in XeO 4? A +8 B +6 C +4 D +2 E 0 Electrochemistry 1. Element M reacts with oxygen to from an oxide with the formula MO. When MO is dissolved in water, the resulting solution is basic. Element M is most likely: A. Na B. Ba C. S D. N E.

More information

Chemistry 102 Chapter 19 OXIDATION-REDUCTION REACTIONS

Chemistry 102 Chapter 19 OXIDATION-REDUCTION REACTIONS OXIDATION-REDUCTION REACTIONS Some of the most important reaction in chemistry are oxidation-reduction (redox) reactions. In these reactions, electrons transfer from one reactant to the other. The rusting

More information

1.In which of the following is the oxidation number of the underlined element given incorrectly? oxidation number

1.In which of the following is the oxidation number of the underlined element given incorrectly? oxidation number General Chemistry II Exam 4 Practice Problems 1 1.In which of the following is the oxidation number of the underlined element given incorrectly? oxidation number a. K 2 Cr 2 O 7 +6 b. NaAl(OH) 4 +3 c.

More information

Oxidation-Reduction Review. Electrochemistry. Oxidation-Reduction Reactions. Oxidation-Reduction Reactions. Sample Problem.

Oxidation-Reduction Review. Electrochemistry. Oxidation-Reduction Reactions. Oxidation-Reduction Reactions. Sample Problem. 1 Electrochemistry Oxidation-Reduction Review Topics Covered Oxidation-reduction reactions Balancing oxidationreduction equations Voltaic cells Cell EMF Spontaneity of redox reactions Batteries Electrolysis

More information

Chapter 17. Electrochemistry

Chapter 17. Electrochemistry Chapter 17 Electrochemistry Contents Galvanic cells Standard reduction potentials Cell potential, electrical work, and free energy Dependence of cell potential on concentration Batteries Corrosion Electrolysis

More information

CHAPTER 5 REVIEW. C. CO 2 D. Fe 2 O 3. A. Fe B. CO

CHAPTER 5 REVIEW. C. CO 2 D. Fe 2 O 3. A. Fe B. CO CHAPTER 5 REVIEW 1. The following represents the process used to produce iron from iron III oxide: Fe 2 O 3 + 3CO 2Fe + 3CO 2 What is the reducing agent in this process? A. Fe B. CO C. CO 2 D. Fe 2 O 3

More information

ELECTROCHEMISTRY OXIDATION-REDUCTION

ELECTROCHEMISTRY OXIDATION-REDUCTION ELECTROCHEMISTRY Electrochemistry involves the relationship between electrical energy and chemical energy. OXIDATION-REDUCTION REACTIONS SPONTANEOUS REACTIONS Can extract electrical energy from these.

More information

(aq) 5VO2 + (aq) + Mn 2+ (aq) + 10H + + 4H 2 O. (aq) 5VO2 + (aq) + Mn 2+ (aq) + 2H + (aq) basic solution. MnO2 + 2H 2 O) 3H 2 O + I IO 3

(aq) 5VO2 + (aq) + Mn 2+ (aq) + 10H + + 4H 2 O. (aq) 5VO2 + (aq) + Mn 2+ (aq) + 2H + (aq) basic solution. MnO2 + 2H 2 O) 3H 2 O + I IO 3 Chem 1515 Section 2 Problem Set #15 Spring 1998 Name ALL work must be shown to receive full credit. Due Due in lecture at 1:30 p.m. Friday, May 1st. PS15.1. Balance the following oxidation-reduction reactions

More information

Oxidation-Reduction (Redox)

Oxidation-Reduction (Redox) Oxidation-Reduction (Redox) Electrochemistry involves the study of the conversions between chemical and electrical energy. Voltaic (galvanic) cells use chemical reactions to produce an electric current.

More information

Practice Exam Topic 9: Oxidation & Reduction

Practice Exam Topic 9: Oxidation & Reduction Name Practice Exam Topic 9: Oxidation & Reduction 1. What are the oxidation numbers of the elements in sulfuric acid, H 2 SO 4? Hydrogen Sulfur Oxygen A. +1 +6 2 B. +1 +4 2 C. +2 +1 +4 D. +2 +6 8 2. Consider

More information

25. A typical galvanic cell diagram is:

25. A typical galvanic cell diagram is: Unit VI(6)-III: Electrochemistry Chapter 17 Assigned Problems Answers Exercises Galvanic Cells, Cell Potentials, Standard Reduction Potentials, and Free Energy 25. A typical galvanic cell diagram is: The

More information

Spontaneous Redox Between Zinc Metal and Copper(II) Ions. Zn 2+ Zn + 2e- Cu 2+ NO 3

Spontaneous Redox Between Zinc Metal and Copper(II) Ions. Zn 2+ Zn + 2e- Cu 2+ NO 3 Spontaneous Redox Between Zinc Metal and Copper(II) Ions Zn 2+ Cu 2+ NO 3 _ Zn + 2e- Cu Zn 0 + Cu 2+ º Zn 2+ + Cu 0 spontaneous red 1 ox 2 ox 1 red 2 Spontaneous Redox Between Copper Metal and Silver Ions

More information

Chapter 19 ElectroChemistry

Chapter 19 ElectroChemistry Chem 1046 General Chemistry by Ebbing and Gammon, 9th Edition George W.J. Kenney, Jr, Professor of Chemistry Last Update: 11July2009 Chapter 19 ElectroChemistry These Notes are to SUPPLIMENT the Text,

More information

Electrochemistry 1 1

Electrochemistry 1 1 Electrochemistry 1 1 Half-Reactions 1. Balancing Oxidation Reduction Reactions in Acidic and Basic Solutions Voltaic Cells 2. Construction of Voltaic Cells 3. Notation for Voltaic Cells 4. Cell Potential

More information

Unit #8, Chapter 10 Outline Electrochemistry and Redox Reactions

Unit #8, Chapter 10 Outline Electrochemistry and Redox Reactions Unit #8, Chapter 10 Outline Electrochemistry and Redox Reactions Lesson Topics Covered Homework Questions and Assignments 1 Introduction to Electrochemistry definitions 1. Read pages 462 467 2. On page

More information

Lecture Presentation. Chapter 18. Electrochemistry. Sherril Soman Grand Valley State University Pearson Education, Inc.

Lecture Presentation. Chapter 18. Electrochemistry. Sherril Soman Grand Valley State University Pearson Education, Inc. Lecture Presentation Chapter 18 Electrochemistry Sherril Soman Grand Valley State University Harnessing the Power in Nature The goal of scientific research is to understand nature. Once we understand the

More information

AP Chemistry: Electrochemistry Multiple Choice Answers

AP Chemistry: Electrochemistry Multiple Choice Answers AP Chemistry: Electrochemistry Multiple Choice Answers 14. Questions 14-17 The spontaneous reaction that occurs when the cell in the picture operates is as follows: 2Ag + + Cd (s) à 2 Ag (s) + Cd 2+ (A)

More information

Electrochemistry. Galvanic Cell. Page 1. Applications of Redox

Electrochemistry. Galvanic Cell. Page 1. Applications of Redox Electrochemistry Applications of Redox Review Oxidation reduction reactions involve a transfer of electrons. OIL- RIG Oxidation Involves Loss Reduction Involves Gain LEO-GER Lose Electrons Oxidation Gain

More information

Chapter 20. Electrochemistry

Chapter 20. Electrochemistry Chapter 20. Electrochemistry 20.1 Oxidation-Reduction Reactions Oxidation-reduction reactions = chemical reactions in which the oxidation state of one or more substance changes (redox reactions). Recall:

More information

Q1. Why does the conductivity of a solution decrease with dilution?

Q1. Why does the conductivity of a solution decrease with dilution? Q1. Why does the conductivity of a solution decrease with dilution? A1. Conductivity of a solution is the conductance of ions present in a unit volume of the solution. On dilution the number of ions per

More information

Chapter 20 Electrochemistry

Chapter 20 Electrochemistry Chapter 20 Electrochemistry Learning goals and key skills: Identify oxidation, reduction, oxidizing agent, and reducing agent in a chemical equation Complete and balance redox equations using the method

More information

Oxidation refers to any process in which the oxidation number of an atom becomes more positive

Oxidation refers to any process in which the oxidation number of an atom becomes more positive Lecture Notes 3 rd Series: Electrochemistry Oxidation number or states When atoms gain or lose electrons they are said to change their oxidation number or oxidation state. If an element has gained electrons

More information

Name AP CHEM / / Collected Essays Chapter 17

Name AP CHEM / / Collected Essays Chapter 17 Name AP CHEM / / Collected Essays Chapter 17 1980 - #2 M(s) + Cu 2+ (aq) M 2+ (aq) + Cu(s) For the reaction above, E = 0.740 volt at 25 C. (a) Determine the standard electrode potential for the reaction

More information

Chapter Nineteen. Electrochemistry

Chapter Nineteen. Electrochemistry Chapter Nineteen Electrochemistry 1 Electrochemistry The study of chemical reactions through electrical circuits. Monitor redox reactions by controlling electron transfer REDOX: Shorthand for REDuction-OXidation

More information

Redox reactions & electrochemistry

Redox reactions & electrochemistry Redox reactions & electrochemistry Electrochemistry Electrical energy ; Chemical energy oxidation/reduction = redox reactions Electrochemistry Zn + Cu 2+ º Zn 2+ + Cu Oxidation-reduction reactions always

More information

A voltaic cell using the following reaction is in operation: 2 Ag + (lm) + Cd(s) 2 Ag(s) + Cd 2+ (l M)

A voltaic cell using the following reaction is in operation: 2 Ag + (lm) + Cd(s) 2 Ag(s) + Cd 2+ (l M) 0. Cu (s) + 2Ag + Cu 2+ + 2Ag (s) If the equilibrium constant for the reaction above is 3.7x10 15, which of the following correctly describes the standard voltage, E o and the standard free energy change,

More information

REVIEW QUESTIONS Chapter 19

REVIEW QUESTIONS Chapter 19 Chemistry 10 ANSWER KEY REVIEW QUESTIONS Chapter 19 1. For each of the following unbalanced equations, (i) write the half-reactions for oxidation and reduction, and (ii) balance the overall equation in

More information

CHEM J-14 June 2014

CHEM J-14 June 2014 CHEM1101 2014-J-14 June 2014 An electrochemical cell consists of an Fe 2+ /Fe half cell with unknown [Fe 2+ ] and a Sn 2+ /Sn half-cell with [Sn 2+ ] = 1.10 M. The electromotive force (electrical potential)

More information

(for tutoring, homework help, or help with online classes)

(for tutoring, homework help, or help with online classes) www.tutor-homework.com (for tutoring, homework help, or help with online classes) 1. chem10b 20.4-3 In a voltaic cell electrons flow from the anode to the cathode. Value 2. chem10b 20.1-35 How many grams

More information

Chapter 18 problems (with solutions)

Chapter 18 problems (with solutions) Chapter 18 problems (with solutions) 1) Assign oxidation numbers for the following species (for review see section 9.4) a) H2SO3 H = +1 S = +4 O = -2 b) Ca(ClO3)2 Ca = +2 Cl = +5 O = -2 c) C2H4 C = -2

More information

Chapter 19: Electrochemistry

Chapter 19: Electrochemistry Chapter 19: Electrochemistry Overview of the Chapter review oxidation-reduction chemistry basics galvanic cells spontaneous chemical reaction generates a voltage set-up of galvanic cell & identification

More information

(c) dilute solution of glucose (d) chloroform 12 Which one of the following represents the same net reaction as the electrolysis of aqueous H2SO4

(c) dilute solution of glucose (d) chloroform 12 Which one of the following represents the same net reaction as the electrolysis of aqueous H2SO4 1 Electrolysis is the process in which a chemical reaction takes place at the expense of (a) chemical energy (b) electrical energy (c) heat energy (d) none of these 2 Standard hydrogen electrode has an

More information

Electrochemistry Pulling the Plug on the Power Grid

Electrochemistry Pulling the Plug on the Power Grid Electrochemistry 18.1 Pulling the Plug on the Power Grid 18.3 Voltaic (or Galvanic) Cells: Generating Electricity from Spontaneous Chemical Reactions 18.4 Standard Electrode Potentials 18.7 Batteries:

More information

SCHOOL YEAR CH- 19 OXIDATION-REDUCTION REACTIONS SUBJECT: CHEMISTRY GRADE: 12

SCHOOL YEAR CH- 19 OXIDATION-REDUCTION REACTIONS SUBJECT: CHEMISTRY GRADE: 12 SCHOOL YEAR 2017-18 NAME: CH- 19 OXIDATION-REDUCTION REACTIONS SUBJECT: CHEMISTRY GRADE: 12 TEST A Choose the best answer from the options that follow each question. 1. During oxidation, one or more electrons

More information

Electrochemistry. Chapter 18. Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Electrochemistry. Chapter 18. Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Electrochemistry Chapter 18 Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 1 Electrochemical processes are oxidation-reduction reactions in which: the energy

More information

Chapter 17 Electrochemistry

Chapter 17 Electrochemistry Chapter 17 Electrochemistry 17.1 Galvanic Cells A. Oxidation-Reduction Reactions (Redox Rxns) 1. Oxidation = loss of electrons a. the substance oxidized is the reducing agent 2. Reduction = gain of electrons

More information

Chapter 18 Electrochemistry. Electrochemical Cells

Chapter 18 Electrochemistry. Electrochemical Cells Chapter 18 Electrochemistry Chapter 18 1 Electrochemical Cells Electrochemical Cells are of two basic types: Galvanic Cells a spontaneous chemical reaction generates an electric current Electrolytic Cells

More information

Chapter 20. Electrochemistry

Chapter 20. Electrochemistry Chapter 20. Electrochemistry 20.1 OxidationReduction Reactions Oxidationreduction reactions = chemical reactions in which the oxidation state of one or more substance changes (redox reactions). Recall:

More information

Topic 19 Redox 19.1 Standard Electrode Potentials. IB Chemistry T09D04

Topic 19 Redox 19.1 Standard Electrode Potentials. IB Chemistry T09D04 Topic 19 Redox 19.1 Standard Electrode Potentials IB Chemistry T09D04 19.1 Standard Electrode Potentials 19.1.1 Describe the standard hydrogen electrode. (2) 19.1.2 Define the term standard electrode potential,

More information

CHEM J-14 June 2014

CHEM J-14 June 2014 CHEM1101 2014-J-14 June 2014 An electrochemical cell consists of an Fe 2+ /Fe half cell with unknown [Fe 2+ ] and a Sn 2+ /Sn half-cell with [Sn 2+ ] = 1.10 M. The electromotive force (electrical potential)

More information

20.1 Consider the Brønsted-Lowry acid-base reaction and the redox reaction below. + A

20.1 Consider the Brønsted-Lowry acid-base reaction and the redox reaction below. + A 20 Electrochemistry Visualizing Concepts 20.1 Consider the Brønsted-Lowry acid-base reaction and the redox reaction below. HA + B BH + + A HA H + + A B + H + BH + X(red) + Y + (ox) X + (ox) + Y(red) X(red)

More information

Dr. Anand Gupta

Dr. Anand Gupta By Dr Anand Gupta Mr. Mahesh Kapil Dr. Anand Gupta 09356511518 09888711209 anandu71@yahoo.com mkapil_foru@yahoo.com Electrochemistry Electrolysis Electric energy Chemical energy Galvanic cell 2 Electrochemistry

More information

ELECTROCHEMISTRY. Electrons are transferred from Al to Cu 2+. We can re write this equation as two separate half reactions:

ELECTROCHEMISTRY. Electrons are transferred from Al to Cu 2+. We can re write this equation as two separate half reactions: ELECTROCHEMISTRY A. INTRODUCTION 1. Electrochemistry is the branch of chemistry which is concerned with the conversion of chemical energy to electrical energy, and vice versa. Electrochemical reactions

More information

Oxidation-reduction (redox) reactions

Oxidation-reduction (redox) reactions Oxidation-reduction (redox) reactions Reactions in which there are changes in oxidation state (oxidation number) between reactants and products 2 MnO 4- + 10 Br - + 16 H + 2 Mn 2+ + 5 Br 2 + 8 H 2 O One

More information

CHEM J-12 June 2013

CHEM J-12 June 2013 CHEM1101 2013-J-12 June 2013 In concentration cells no net chemical conversion occurs, however a measurable voltage is present between the two half-cells. Explain how the voltage is produced. 2 In concentration

More information

Electrochemistry. 1. Determine the oxidation states of each element in the following compounds. (Reference: Ex. 4:16) a. N 2 N: b.

Electrochemistry. 1. Determine the oxidation states of each element in the following compounds. (Reference: Ex. 4:16) a. N 2 N: b. Name: Electrochemistry Two of the most common types of chemical reactions are acid-base reactions in which protons are transferred between two reactants and oxidation-reduction reactions in which electrons

More information

Ch 20 Electrochemistry: the study of the relationships between electricity and chemical reactions.

Ch 20 Electrochemistry: the study of the relationships between electricity and chemical reactions. Ch 20 Electrochemistry: the study of the relationships between electricity and chemical reactions. In electrochemical reactions, electrons are transferred from one species to another. Learning goals and

More information

Chapter 18: Electrochemistry

Chapter 18: Electrochemistry Chapter 18: Electrochemistry Oxidation States An oxidation-reduction reaction, or redox reaction, is one in which electrons are transferred. 2Na + Cl 2 2NaCl Each sodium atom is losing one electron to

More information

AP Questions: Electrochemistry

AP Questions: Electrochemistry AP Questions: Electrochemistry I 2 + 2 S 2O 2-3 2 I - + S 4O 2-6 How many moles of I 2 was produced during the electrolysis? The hydrogen gas produced at the cathode during the electrolysis was collected

More information

Chapter 18 Electrochemistry

Chapter 18 Electrochemistry Chapter 18 Electrochemistry Definition The study of the interchange of chemical and electrical energy in oxidation-reduction (redox) reactions This interchange can occur in both directions: 1. Conversion

More information

Chapter 20. Electrochemistry

Chapter 20. Electrochemistry Chapter 20. Electrochemistry Sample Exercise 20.1 (p. 845) The nickelcadmium (nicad) battery, a rechargeable dry cell used in batteryoperated devices, uses the following redox reaction to generate electricity:

More information

Oxidation number. The charge the atom would have in a molecule (or an ionic compound) if electrons were completely transferred.

Oxidation number. The charge the atom would have in a molecule (or an ionic compound) if electrons were completely transferred. Oxidation number The charge the atom would have in a molecule (or an ionic compound) if electrons were completely transferred. 1. Free elements (uncombined state) have an oxidation number of zero. Na,

More information

Guide to Chapter 18. Electrochemistry

Guide to Chapter 18. Electrochemistry Guide to Chapter 18. Electrochemistry We will spend three lecture days on this chapter. During the first class meeting we will review oxidation and reduction. We will introduce balancing redox equations

More information

CHEMISTRY - CLUTCH CH.18 - ELECTROCHEMISTRY.

CHEMISTRY - CLUTCH CH.18 - ELECTROCHEMISTRY. !! www.clutchprep.com CONCEPT: OXIDATION-REDUCTION REACTIONS Chemists use some important terminology to describe the movement of electrons. In reactions we have the movement of electrons from one reactant

More information

Review. Chapter 17 Electrochemistry. Outline. Voltaic Cells. Electrochemistry. Mnemonic

Review. Chapter 17 Electrochemistry. Outline. Voltaic Cells. Electrochemistry. Mnemonic Review William L Masterton Cecile N. Hurley Edward J. Neth cengage.com/chemistry/masterton Chapter 17 Electrochemistry Oxidation Loss of electrons Occurs at electrode called the anode Reduction Gain of

More information

Ch 11 Practice Problems

Ch 11 Practice Problems Ch 11 Practice Problems 1. How many electrons are transferred in the following reaction? 2Cr 2O 7 2- + 14H + + 6Cl 2Cr 3+ + 3Cl 2 + 7H 2O A) 2 B) 4 C) 6 D) 8 2. Which metal, Al or Ni, could reduce Zn 2+

More information

How to Assign Oxidation Numbers. Chapter 18. Principles of Reactivity: Electron Transfer Reactions. What is oxidation? What is reduction?

How to Assign Oxidation Numbers. Chapter 18. Principles of Reactivity: Electron Transfer Reactions. What is oxidation? What is reduction? Chapter 18 Principles of Reactivity: Electron Transfer Reactions What is oxidation? When a molecule/ion loses electrons (becomes more positive) Whatever is oxidized is the reducing agent What is reduction?

More information

Oxidation Numbers, ox #

Oxidation Numbers, ox # Oxidation Numbers, ox # are or numbers assigned to each or assuming that the are transferred from the electronegative element to the electronegative element. now mimic systems. ox # are written followed

More information

Chpt 20: Electrochemistry

Chpt 20: Electrochemistry Cell Potential and Free Energy When both reactants and products are in their standard states, and under constant pressure and temperature conditions where DG o = nfe o DG o is the standard free energy

More information

Chapter 18. Electrochemistry

Chapter 18. Electrochemistry Chapter 18 Electrochemistry Section 17.1 Spontaneous Processes and Entropy Section 17.1 http://www.bozemanscience.com/ap-chemistry/ Spontaneous Processes and Entropy Section 17.1 Spontaneous Processes

More information

1.11 Electrochemistry

1.11 Electrochemistry 1.11 Electrochemistry Recap from 1.7: Oxidation and Reduction: Oxidation and Reduction: Oxidation and reduction reactions can be identified by looking at the reaction in terms of electron transfer: Definitions:

More information

Name: Regents Chemistry Date:

Name: Regents Chemistry Date: Name: Date: 1. The reaction CuO + CO CO 2 + Cu is an example of (A) reduction, only (B) oxidation, only (C) both oxidation and reduction (D) neither oxidation nor reduction 6. In which compound does chlorine

More information

Electron Transfer Reactions

Electron Transfer Reactions ELECTROCHEMISTRY 1 Electron Transfer Reactions 2 Electron transfer reactions are oxidation- reduction or redox reactions. Results in the generation of an electric current (electricity) or be caused by

More information

Electrochemistry Pearson Education, Inc. Mr. Matthew Totaro Legacy High School AP Chemistry

Electrochemistry Pearson Education, Inc. Mr. Matthew Totaro Legacy High School AP Chemistry 2012 Pearson Education, Inc. Mr. Matthew Totaro Legacy High School AP Chemistry Electricity from Chemistry Many chemical reactions involve the transfer of electrons between atoms or ions electron transfer

More information

Electrochem: It s Got Potential!

Electrochem: It s Got Potential! Electrochem: It s Got Potential! Presented by: Denise DeMartino Westlake High School, Eanes ISD Pre-AP, AP, and Advanced Placement are registered trademarks of the College Board, which was not involved

More information

Chapter 20 Electrochemistry

Chapter 20 Electrochemistry Chapter 20 Electrochemistry 20.1 Oxidation States and Oxidation-Reduction Reactions An oxidation occurs when an atom or ion loses electrons. A reduction occurs when an atom or ion gains electrons. One

More information

Oxidation & Reduction (Redox) Notes

Oxidation & Reduction (Redox) Notes Oxidation & Reduction (Redox) Notes Chemical Activity (or Chemical Reactivity) is the measure of the reactivity of elements. If an element has high activity, then it means that the element is willing to

More information

Chapter 9 Oxidation-Reduction Reactions. An Introduction to Chemistry by Mark Bishop

Chapter 9 Oxidation-Reduction Reactions. An Introduction to Chemistry by Mark Bishop Chapter 9 Oxidation-Reduction Reactions An Introduction to Chemistry by Mark Bishop Chapter Map Oxidation Historically, oxidation meant reacting with oxygen. 2Zn(s) + O 2 (g) 2ZnO(s) Zn Zn 2+ + 2e or 2Zn

More information

Bubble in A, B or C as the test form code at the top right of your answer sheet. Bubble in your Section Number also. VERSION X

Bubble in A, B or C as the test form code at the top right of your answer sheet. Bubble in your Section Number also. VERSION X CHM 2046 Practice Exam 3 Bubble in A, B or C as the test form code at the top right of your answer sheet. Bubble in your Section Number also. VERSION X 1. A reaction has ΔH = -75.0 kj and ΔS = -245 J/K.

More information

Lecture Presentation. Chapter 20. Electrochemistry. James F. Kirby Quinnipiac University Hamden, CT Pearson Education

Lecture Presentation. Chapter 20. Electrochemistry. James F. Kirby Quinnipiac University Hamden, CT Pearson Education Lecture Presentation Chapter 20 James F. Kirby Quinnipiac University Hamden, CT is the study of the relationships between electricity and chemical reactions. It includes the study of both spontaneous and

More information

CHAPTER 17 ELECTROCHEMISTRY

CHAPTER 17 ELECTROCHEMISTRY Advanced Chemistry Approximate Timeline Students are expected to keep up with class work when absent. CHAPTER 17 ELECTROCHEMISTRY Day Plans for the day Assignment(s) for the day 17.1 Galvanic Cells Assignment

More information

Chemistry 12 JANUARY Course Code = CH. Student Instructions

Chemistry 12 JANUARY Course Code = CH. Student Instructions MINISTRY USE ONLY MINISTRY USE ONLY Place Personal Education Number (PEN) here. Place Personal Education Number (PEN) here. MINISTRY USE ONLY Chemistry 12 2002 Ministry of Education JANUARY 2002 Course

More information

17.1 Redox Chemistry Revisited

17.1 Redox Chemistry Revisited Chapter Outline 17.1 Redox Chemistry Revisited 17.2 Electrochemical Cells 17.3 Standard Potentials 17.4 Chemical Energy and Electrical Work 17.5 A Reference Point: The Standard Hydrogen Electrode 17.6

More information

Chapter 19: Oxidation - Reduction Reactions

Chapter 19: Oxidation - Reduction Reactions Chapter 19: Oxidation - Reduction Reactions 19-1 Oxidation and Reduction I. Oxidation States A. The oxidation rules (as summarized by Mr. Allan) 1. In compounds, hydrogen has an oxidation # of +1. In compounds,

More information

AQA A2 CHEMISTRY TOPIC 5.3 REDOX EQUILIBRIA BOOKLET OF PAST EXAMINATION QUESTIONS

AQA A2 CHEMISTRY TOPIC 5.3 REDOX EQUILIBRIA BOOKLET OF PAST EXAMINATION QUESTIONS AQA A2 CHEMISTRY TOPIC 5.3 REDOX EQUILIBRIA BOOKLET OF PAST EXAMINATION QUESTIONS 1. (a) Define the term oxidising agent in terms of electrons.... 2. Use the data in the table below, where appropriate,

More information

Unit - 3 ELECTROCHEMISTRY VSA QUESTIONS (1 - MARK QUESTIONS) 3. Mention the purpose of salt-bridge placed between two half-cells of a galvanic cell?

Unit - 3 ELECTROCHEMISTRY VSA QUESTIONS (1 - MARK QUESTIONS) 3. Mention the purpose of salt-bridge placed between two half-cells of a galvanic cell? Unit - 3 ELECTROCHEMISTRY 1. What is a galvanic cell? VSA QUESTIONS (1 - MARK QUESTIONS) 2. Give the cell representation for Daniell Cell. 3. Mention the purpose of salt-bridge placed between two half-cells

More information

Unit 8 Redox 8-1. At the end of this unit, you ll be able to

Unit 8 Redox 8-1. At the end of this unit, you ll be able to 8-1 Unit 8 Redox At the end of this unit, you ll be able to Define and identify oxidation reactions Define and identify reduction reactions Assign oxidation numbers to elements in a compound Write and

More information

Chem II. Zn(s) + CuSO4(aq)

Chem II. Zn(s) + CuSO4(aq) Redox Review Chem II 1. What is the sum of the oxidation numbers of the atoms in the compound CO2? A) 0 B) 2 C) 4 D) +4 2. In which substance does phosphorus have a +3 oxidation state? A) P4O10 B) PCl5

More information

Section A: Summary Notes

Section A: Summary Notes ELECTROCHEMICAL CELLS 25 AUGUST 2015 Section A: Summary Notes Important definitions: Oxidation: the loss of electrons by a substance during a chemical reaction Reduction: the gain of electrons by a substance

More information

SHOCK TO THE SYSTEM! ELECTROCHEMISTRY

SHOCK TO THE SYSTEM! ELECTROCHEMISTRY SHOCK TO THE SYSTEM! ELECTROCHEMISTRY REVIEW I. Re: Balancing Redox Reactions. A. Every redox reaction requires a substance to be... 1. oxidized (loses electrons). a.k.a. reducing agent 2. reduced (gains

More information

CHEM N-12 November In the electrolytic production of Al, what mass of Al can be deposited in 2.00 hours by a current of 1.8 A?

CHEM N-12 November In the electrolytic production of Al, what mass of Al can be deposited in 2.00 hours by a current of 1.8 A? CHEM161 014-N-1 November 014 In the electrolytic production of Al, what mass of Al can be deposited in.00 hours by a current of 1.8 A? What products would you expect at the anode and the cathode on electrolysis

More information

Part One: Introduction. a. Chemical reactions produced by electric current. (electrolysis)

Part One: Introduction. a. Chemical reactions produced by electric current. (electrolysis) CHAPTER 19: ELECTROCHEMISTRY Part One: Introduction A. Terminology. 1. Electrochemistry deals with: a. Chemical reactions produced by electric current. (electrolysis) b. Production of electric current

More information

Chapter 20. Electrochemistry Recommendation: Review Sec. 4.4 (oxidation-reduction reactions) in your textbook

Chapter 20. Electrochemistry Recommendation: Review Sec. 4.4 (oxidation-reduction reactions) in your textbook Chapter 20. Electrochemistry Recommendation: Review Sec. 4.4 (oxidation-reduction reactions) in your textbook 20.1 Oxidation-Reduction Reactions Oxidation-reduction reactions = chemical reactions in which

More information

The Nature of Redox. Both oxidation and reduction processes occur together. Each half of the full redox reaction is a. Oxidizing and Reducing Agents

The Nature of Redox. Both oxidation and reduction processes occur together. Each half of the full redox reaction is a. Oxidizing and Reducing Agents V. ELECTROCHEMISTRY V.1 INTRODUCTION TO OXIDATION AND REDUCTION Key Question: How are electrons gained or lost? ELECTROCHEMISTRY is the study of oxidation and reduction reactions in which chemical species

More information

DO NOT USE A CALCULATOR.

DO NOT USE A CALCULATOR. Practice Test 20.1 (va pg 1 of 5) This is practice - Do NOT cheat yourself of finding out what you are capable of doing. Be sure you follow the testing conditions outlined below. DO NOT USE A CALCULATOR.

More information

Homework #3 Chapter 11 Electrochemistry

Homework #3 Chapter 11 Electrochemistry Homework #3 Chapter 11 Electrochemistry Chapter 4 83. a) Oxidation ½ Reaction Fe + HCl HFeCl 4 Fe + 4HCl HFeCl 4 Fe + 4HCl HFeCl 4 + 3H + Fe + 4HCl HFeCl 4 + 3H + + 3e Reduction ½ Reaction H 2 2H + H 2

More information

Oxidation (oxidized): the loss of one or more electrons. Reduction (reduced): the gain of one or more electrons

Oxidation (oxidized): the loss of one or more electrons. Reduction (reduced): the gain of one or more electrons 1 of 13 interesting links: Battery Chemistry Tutorial at http://www.powerstream.com/batteryfaq.html Duracell Procell: Battery Chemistry at http://www.duracell.com/procell/chemistries /default.asp I. Oxidation

More information

Lecture 14. Thermodynamics of Galvanic (Voltaic) Cells.

Lecture 14. Thermodynamics of Galvanic (Voltaic) Cells. Lecture 14 Thermodynamics of Galvanic (Voltaic) Cells. 51 52 Ballard PEM Fuel Cell. 53 Electrochemistry Alessandro Volta, 1745-1827, Italian scientist and inventor. Luigi Galvani, 1737-1798, Italian scientist

More information

Chemistry 12. Resource Exam B. Exam Booklet

Chemistry 12. Resource Exam B. Exam Booklet Chemistry 12 Resource Exam B Exam Booklet Contents: 21 pages Examination: 2 hours 50 multiple-choice questions in the Exam Booklet Additional Time Permitted: 60 minutes Province of British Columbia PART

More information

Chapter 7. Oxidation-Reduction Reactions

Chapter 7. Oxidation-Reduction Reactions Chapter 7 Oxidation-Reduction Reactions Chapter Map Oxidation Historically oxidation meant reacting with oxygen. 2Zn(s) + O 2 (g) 2ZnO(s) Zn Zn 2+ + 2e or 2Zn 2Zn 2+ + 4e O + 2e O 2 or O 2 + 4e 2O 2 Oxidation

More information

Introduction Oxidation/reduction reactions involve the exchange of an electron between chemical species.

Introduction Oxidation/reduction reactions involve the exchange of an electron between chemical species. Introduction Oxidation/reduction reactions involve the exchange of an electron between chemical species. The species that loses the electron is oxidized. The species that gains the electron is reduced.

More information

Lecture Presentation. Chapter 20. Electrochemistry. James F. Kirby Quinnipiac University Hamden, CT Pearson Education, Inc.

Lecture Presentation. Chapter 20. Electrochemistry. James F. Kirby Quinnipiac University Hamden, CT Pearson Education, Inc. Lecture Presentation Chapter 20 James F. Kirby Quinnipiac University Hamden, CT is the study of the relationships between electricity and chemical reactions. It includes the study of both spontaneous and

More information

Electrochemistry. Outline

Electrochemistry. Outline Electrochemistry Outline 1. Oxidation Numbers 2. Voltaic Cells 3. Calculating emf or Standard Cell Potential using Half-Reactions 4. Relationships to Thermo, Equilibrium, and Q 5. Stoichiometry 6. Balancing

More information

Homework 11. Electrochemical Potential, Free Energy, and Applications

Homework 11. Electrochemical Potential, Free Energy, and Applications HW11 Electrochemical Poten!al, Free Energy, and Applica!ons Homework 11 Electrochemical Potential, Free Energy, and Applications Question 1 What is the E for Zn(s) Zn (aq) Ce (aq) Ce (aq) + cell + 4+ 3+

More information

Sample Exercise 20.2 Practice Exercise 1 with feedback

Sample Exercise 20.2 Practice Exercise 1 with feedback Homework Chapter 20 Due: 11:59pm on Wednesday, November 16, 2016 You will receive no credit for items you complete after the assignment is due. Grading Policy Sample Exercise 20.2 Practice Exercise 1 with

More information

Electrochemistry (Galvanic and Electrolytic Cells) Exchange of energy in chemical cells

Electrochemistry (Galvanic and Electrolytic Cells) Exchange of energy in chemical cells Electrochemistry (Galvanic and Electrolytic Cells) Exchange of energy in chemical cells Oxidation loss of electrons (oxidation number increases) OIL RIG Reduction gain of electrons (oxidation number decreases)

More information

Lecture Presentation. Chapter 20. Electrochemistry. James F. Kirby Quinnipiac University Hamden, CT Pearson Education

Lecture Presentation. Chapter 20. Electrochemistry. James F. Kirby Quinnipiac University Hamden, CT Pearson Education Lecture Presentation Chapter 20 James F. Kirby Quinnipiac University Hamden, CT is the study of the relationships between electricity and chemical reactions. It includes the study of both spontaneous and

More information

Chemistry: The Central Science. Chapter 20: Electrochemistry

Chemistry: The Central Science. Chapter 20: Electrochemistry Chemistry: The Central Science Chapter 20: Electrochemistry Redox reaction power batteries Electrochemistry is the study of the relationships between electricity and chemical reactions o It includes the

More information

mccord (pmccord) HW11 Electrochemistry I mccord (51520) 1

mccord (pmccord) HW11 Electrochemistry I mccord (51520) 1 mccord (pmccord) HW11 Electrochemistry I mccord (51520) 1 This print-out should have 27 questions. Multiple-choice questions may continue on the next column or page find all choices before answering. 001

More information