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1) Which most readily gains electrons?

Cu

Cu^+2

Fe^+2

Zn^+2

Au^+3

2) Which most readily loses electrons?

Hg(l)

Cu^+2

Sn^+4

Ba

Al

Calculate the cell potentials or voltages (E⁰) Indicatespontaneity.

3. Cl₂ + 2Br^- -----> 2Cl^- +Br₂

4. 2MnO₄^- + 5Pb + 16H⁺ ----->2Mn⁺² + 8H₂O + 5Pb⁺²

5. Will AgNO₃ react with Zn? Write a balanced redoxreaction and calculate E^o

6. What would happen if you used an iron spoon to stir a soulutionof Al₂(SO₄)₃(aq) ? Write a balancedredox reaction and calculate E^o.

7) What are the differences between an electrochemical cell and anelectrolytic cell?

electrochemical cell

electrolytic cell

8) What are the similarities between an electrochemical cell andan electrolytic cell?

electrochemical cell or electrolytic cell

9) State how you would determine each of the following in anelectrochemical or electrolytic cell.

	Electrochemical Cell	Electrolytic Cell
The site of reduction
The site of oxidation
The +ve electrode
The -ve electrode
The anions migrate to the
The cations migrate to the
The electrode that gains mass
The electrode that loses mass
The electrons flow from

10.a) Draw an operating electrochemical cellusing an Al half-cell and a Mg half-cell. Label the parts of theelectrochemical cell including the anode or cathode, and all reagentsand materials used. Write the reactions and determine theE⁰.

11. (a) Write the half reaction that occursat each electrode during the electrolysis of aqueous 1 M NaI.

Anode :

Cathode :

(b) What is the minimum required voltage forthis process?

12. (a) Write the half reaction that occursat each electrode during the electrolysis of molton NaI.

Anode :

Cathode :

(b) What is the minimum required voltage forthis process?

13. Aluminum is produced industrially from aluminum oxide,Al₂O₃. Demonstrate your understanding of thisprocess by

(i) describing how the process is carried out,

(ii) writing equations of the reactions involved in the process,and

(iii) describing how the problem of the high melting point ofAl₂O₃ is overcome.

14. Consider the following redoxdata:

3V +2Ga³⁺ ----> 3V²⁺ + 2GaE=+0.64V

3V²⁺ + 2Al ---->3V + 2 Al³⁺ E=+0.46V

Based on these observations, a studentconcludes that Ga⁺³ and Al willreact spontaneously. List the oxidizing agents in order of decreasingstrength. Write reduction reactions for each. Determine the strongestreducing agent. Determine if Ga⁺³ and Al willreact spontaneously.

15. Balance the equation for the followinghalf reaction occuring in acid solution:

V_(s)----->HV₂O₇^-3

16. Balance the following redox reactionoccuring in basic solution:

MnO₄^-+C₂O₄^-2 ----->MnO₂ +CO₂

17. 250ml .200M MnO_4- reacts with excessSO₃^-2. How many grams of MnO₂ areproduced?

2MnO₄^- + 3SO₃^-2 +H₂O -----> 2MnO₂ +3SO₄^-2 + 2OH^-

18. Determine the oxidation number for each bold atom.

MnO2	IO3^-	Cr2O7^-2	C2O4^-2	Al(NO3)3	NH4Cl	NaH
HOOH	NO3^-	H3PO4	Na2C2O4	I2	N2O3	Pt(H2O)4^+2

19. 250ml of .500M MnO₄^- are required totitrate a 100ml sample of SO₃^-2. Calculate the[SO₃^-2]

2MnO₄^- + 3SO₃^-2 +H₂O -----> 2MnO₂ + 3SO₄^-2+ 2OH^-

20. How is the breathalyzer reaction used to determine BAC? Writethe reaction and describe how it works.

21. 2H⁺ + Mg-----> Mg⁺² +H₂

Determine the Oxidizing agent__________ and the Reducingagent_________

22. Choose a suitable redox reactant to oxidize Cl^- toClO₄^- in a redox titration.

23. Describe as an electrochemical or electrolytic cell:

a) Fuel cell

b) Charging a car battery

c) Discharging a car battery

d) Ni plating

e) Industrial Al production

f) Cl₂ production

g) Electrowinning

24) Which of the reactants is gaining electrons? Which of thereactants is the oxidizing agent?

Br₂ + SO₂+Na₂SO₄ +H₂O -------->2H₂SO₄ + 2NaBr

25) A student studied the following reactions and she recorded:

Pd⁺² + Cu -------> Pd + Cu⁺² spontaneous

Pd⁺² + Au -------> no reaction

Pd⁺² + Hg -------> no reaction

Au⁺³ + Hg -------> Au + Hg⁺² spontaneous

List the oxidizing agents from strongest to weakest. List thereducing agents from strongest to weakest. Predict if the reactionwill occur.

Au⁺³ + Cu ------------>

26) Match each type of electrolytic cell with the example cell.

Electrowinning	A silver anode oxidizes & Ag reduces on a Cu cathode
Electroplating	Pure Pb is reduced at the cathode while impure Pb oxidizes at the anode
Electrorefining	Pure Al is reduced at the cathode from molten bauxite (Al2O3).

27. List the anode, cathode, anode reaction , cathode reaction,and electrolyte for each commercial electrochemical cell.

Cell	anode	anode reaction	cathode	cathode reaction	electrolyte
Leclanche or Common Dry Cell
Alkaline Cell
Lead Storage or Car Battery
Fuel Cell

28. Which of the above cells requires continuous input ofO₂ and H₂ and is produced by BallardIndustries.

29. List the anode, cathode, anode reaction , cathode reaction,and electrolyte for each commercial electrolytic cell.

Cell	anode	anode reaction	cathode	cathode reaction	electrolyte
Electrolysis of Molten Al2O3
Electrolysis of Aqueous NaCl
Silver-plating a Cu plating
Electrorefining pure Pb from impure Pb

30. Describe each term:

salt bridge

electrolyte

anode

cathode

spontaneous

electronegativity

cation

anion

electrochemical cell

electrolytic cell

oxidation number

electrolysis

oxidation

reduction

oxidizing agent

reducing agent

electrode

corrosion

electrowinning

electrorefining

overpotential effect

fuel cell

31. Define corrosion of a metal, and illustrate yourdefinition with reference to an example, using appropriate equations.Give TWO methods by which corrosion can be prevented and describe howeach method works. The two methods must involve different chemicalprinciples.

32. Explain why you would choose Zn or Cu to cathodically protectiron?

33. A+2 does not react with B, while C+2 reacts with B. Rank theoxidizing agents in decreasing order of strength. Rank the reducingagents in decreasing order of strength. Will A+2 react with C?

34. Write half reactions for each using the reduction table andlist the half cell potential.

	Half Reaction	E^o
oxidation of water
oxidation of water in acid
reduction of water
reduction of water in alkaline
oxidation of H2 in water
oxidation of H2 in acid
oxidation of H2 in base
reduction of Cr2O7^-2 in acid
reduction of HBr

35.Completely analyze the following electrochemical cell.

The anode reaction is:

The cathode reaction is:

The electrons flow from ___ to ___

The ions that migrate to the Zn electrode are:

The ions that migrate to the Cu electrode are:

The intial voltage of this cell is:

The voltage of this cell once equilibrium is reached is:

Describe the change in [Cu⁺²] in the Cu half cell

Describe the change in [NO₃^-1] in the Zn half cell

36. Completely analyze the following electrochemical cell.

The anode reaction is:

The cathode reaction is:

The electrons flow from ___ to ___

The ions that migrate to the Pt electrode are:

The ions that migrate to the Cu electrode are:

The intial voltage of this cell is:

The voltage of this cell once equilibrium is reached is:

Describe the change in [Cu⁺²] in the Cu half cell

Describe the change in [NO₃^-1] in the H⁺/H₂ half cell

37. Completely analyze the following electrolytic cell.

Anode Reaction

Cathode Reaction

Chemicals produced at the anode

Chemicals produced at the cathode

The electrons flow from __to __

The chemical used to lower the mp is:

Which electrode is the anode ?

38. Completely analyze the following electrolytic cell. Note that the electrodes are not inert and because of that, the anode might oxidize.

Anode Reaction

Cathode Reaction

Chemicals produced at the anode

Chemicals produced at the cathode

The electrons flow from

The MTV

Which electrode is the anode ?