Study Outline

Question 1

Represents what is happening to only one reactant in an overall equation.

Answer 1

Half-reaction.

Question 2

A process in which electrons are lost.

Answer 2

Oxidation; LEO; Fe -> Fe3+ + 3e-

Question 3

A process in which electrons are gained.

Answer 3

Reduction; GER; Cu2+ + 2e- -> Cu

Question 4

A chemical reaction where electrons are transferred between particles.

Answer 4

Redox reaction.

Question 5

Electron transfer theory.

Answer 5

Total electrons gained = total electrons lost.

Question 6

Reducing agent; RA

Answer 6

The oxidized substance ie. Fe

Question 7

Oxidizing agent; OA

Answer 7

The reduced substance ie. Cu2+

Question 8

The real or apparent charge an atom or ion posses when bonds are falsely assumed ionic.

Answer 8

Oxidation number.

Question 9

Rules for assigning oxidation numbers.

Answer 9

1. Monatomic ions: charge on ion
2. H: 1+, except hydrides: 1-
3. O: 2-, except peroxides: 1-
4. Atoms in elements (Cl2, O2): 0
5. All others add up to total charge

Question 10

Writing half-reaction equations.

Answer 10

1. Balance other than O, H
2. Balance O, +H2O
3. Balance H, + H+
   Basic: a) Add OH- = H+
   Basic: b) Make H2O, and dump some
4. Add e- to balance charges.

Question 11

Half-reaction method of balancing.

Answer 11

1. Obtain half reactions
2. Balance e-
3. Combine, cancel e-, H2O, H+
4. Check charge balance

Question 12

Oxidation number method of balancing.

Answer 12

1. Assign oxidation numbers
2. Simples oxidation and reduction equations; balance electrons
3. Write redox equation
4. Balance O, +H2O
5. Balance H, + H+
   a) OH-
   b) Make water
6. Check charges

Question 13

Spontaneous reaction.

Answer 13

When the OA is able to take electrons away from the RA.

Question 14

Redox spontaneity rule.

Answer 14

A redox reaction will be spontaneous if the oxidizing agent is above the reducing agent in the redox table.

Question 15

Electric cell (galvanic cell).

Answer 15

Device in which spontaneous redox reaction draws electrons through a conductor producing an electric current.

Question 16

Salt bridge.

Answer 16

Allows ions to move between half-cels to prevent polarization.

Question 17

Reduction potential, E`r.

Answer 17

Measured voltage of a half-cell connected to the standard.

Question 18

Standard half-cell.

Answer 18

Hydrogen, with a reduction potential assumed to be 0.

H2(g)/H+(aq)/ With E`r = 0v

Question 19

Standard cell potential, /\E`.

Answer 19

Can be determined by the summation of the half-cell potentials. /\E`= Ecathode - Eanode.

Question 20

Hydrogen-oxygen fuel cell.

Answer 20

O2 reduced/H2 oxidized

Question 21

Aluminum-air fuel cell.

Answer 21

O2 reduced/Al oxidized

Question 22

Occurance of a non-spontaneous redox reaction driven by external source of electrical energy.

Answer 22

Electrolysis.

Question 23

Metal spontaneously oxidized by substances in the environment.

Answer 23

Corrosion.

Question 24

Protective coatings.

Answer 24

Barrier to environment, ex: paint, oil, metallic coatings

Question 25

Impressed current or sacrificial anode.

Answer 25

Cathodic protection.

Question 26

Molten salt electrolysis.

Answer 26

Producing sodium metal.

[Na+ + e- -> Na / 2Cl- -> Cl2 + 2e-]

Question 27

Production of aluminum.

Answer 27

High voltage

[Al3+ + 3e- -> Al / 2O2- -> O2 + 4e-]

Question 28

Electrorefining.

Answer 28

Production of a pure metal at the cathode using an impure metal at the anode.

Question 29

Electroplating.

Answer 29

Depositing a layer of metal on to another object which is the cathode of an electrolytic cell.

Question 30

Faraday’s Law.

Answer 30

The mass of a substance formed at an electrode is directly related to the charge transferred.
9.65x10^4C of charge per every mole of electrons that flows.

Question 31

Molar charge of electrons, F.

Answer 31

9.65x10^4 C/mol

Question 32

Moles of electrons transferred, Ne-.

Answer 32

It/F.