Terms
Redox Equation
Voltaic & Electrolytic cells 1
Voltaic & Electrolytic cells 2
Questions
100
The loss of electrons
Oxidation
100
Oxidation number: ? : ON=0 ? : ON=charge on the ion ? : ON=-2(usually) ? : ON=+1(usually)
Pure elements Ions Combined oxygen Combined hydrogen
100
____ use the energy released in spontaneous redox reaction to generate electricity.
Voltaic cells
100
Non-spontaneous endothermic reactions require electrical energy, which is converted into chemical energy
Electrolytic cells
100
Voltaic cell is constructed using Ni(2+)/Ni and Zn(2+)/Zn. 1. which is the anode? 2. which has a negative charge? 3. will lose mass?
Zn/Zn/Zn
200
Electrode at which oxidation takes place
Anode
200
1___ + 2____ --> 3____ + 4_____ 1 to 3: accepts electrons, undergoes reduction, decreases its oxidation number 2 to 4: donates electrons/ undergoes oxidation, increases its oxidation number
1: Oxidizing agent 2: Reducing agent 3: Conjugate reducing agent 4: conjugate oxidizing agent
200
Voltaic cells: Ocidation occurs at ___ Reduction occurs at ___ Electrolytic cells: Ocidation occurs at ___ Reduction occurs at ___
Anode/ cathode Anode/ cathode
200
Voltaic Cell: Anode is + or - Cathode is + or - Electrolytic Cell: Anode is + or - Cathode is + or -
-/+ +/-
200
Write a balanced equation for combustion of ethanol
C2H5OH + 3O2 --> 2CO2 + 3H2O
300
A reactant, often a non-metal, that causes another reactant to lose electrons
Oxidation agent
300
CuO(s) + Zn(s) --> ZnO(s) + Cu(s) half equations of Oxidation___ : --> Reduction ___ : -->
Oxidation of Zinc: Zn --> Zn2+ + 2e- Reduction of copper ions: Cu2+ 2e- --> Cu
300
Voltaic cells are composed of two 1___, each containing a 2___ pair. Each 1___ contains an electrode and an electrolyte. 1___ are connected 3 ex/internally by wiring and 4 ex/internally by a 5____.
1: half-cells 2: conjugate redox pair 3: externally 4: internally 5: salt bridge
300
It is an electrolytic conductor, conducting current by the flow of ions. What is it? and example?
Salt bridge/ KNO3
300

Using the activity series or standard reduction potentials table (pg20) write ionic equations for any reaction that would occur when cadmium is added to a solution of Cu(NO3)2.

Cu(2+) + Cd --> Cu + Cd(2+)

400
The potential difference generated by a voltaic cell in which a particular half-cell under standard condition is connected to a standard hydrogen half-cell
Standard electrode potential
400
Write the equations of oxidation of SO2 to SO4(2-) in acidic solution
SO2 + 2H2O --> SO4(2-) + 4H(+) + 2e(-)
400
In electrolytic cells: the strongest oxidizing agent is __ at the __(-) the strongest reducing agent is __ at the __(+)
reduced/ cathode oxidized/ anode
400

Three differences between voltaic cells and electrolytic cells

salt bridge/ no salt bridge anode(-),cathode(+)/anode(+),cathode(-) external circuit/ internal (power source supplies) spontaneous/non-spontaneous etc

400
Explain why it would be unwise to store silver nitrate solution in a copper container.
it will dissolve the Cu container
500
An arrangement consisting of two half-cells connected internally by a salt bridge and externally by wires.
Voltaic cell
500
Write the equations of reduction of Cr2O7(2-) to Cr(3+) in acidic solution
Cr2O7(2-) + 14H(+) + 6e(-) --> 2Cr(3+) + 7H2O
500
In electrolytic cells, power source supplies electrons to ___ and accepts electrons from ___
oxidizing agent/ reducing agent
500

Draw Electrolytic cells nicely

See Ms Rose

500
A solution of hydrogen peroxide reacts with itself over time to produce water and oxygen gas and so solutions of hydrogen peroxide are generally kept in the refrigerator. If I add manganese dioxide, what is the role of this? How does it affect the reaction?
catalyst - increase the rate of reaction
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