Electrochemistry

Question 1

Galvanic (Voltaic) Cells

Answer 1

Electrochemical cell in which a spontaneous redox reaction takes place

Question 2

Half-Cells

Answer 2

Components of a cell that contain the redox conjugate pair (“couple”) of a single reactant

Question 3

Anode

Answer 3

Electrode in an electrochemical cell at which oxidation occurs

Question 4

Cathode

Answer 4

Electrode in an electrochemical cell at which reduction occurs

Question 5

Salt Bridge

Answer 5

Tube filled with inert electrolyte solution

Question 6

Cell Notation (Schematic)

Answer 6

Symbolic representation of the components and reactions in an electrochemical cell

Question 7

Inert Electrode

Answer 7

Electrode that conducts electrons to and from the reactants in a half-cell but that is not itself oxidized or reduced

Question 8

Active Electrode

Answer 8

Electrode that participates as a reactant or product in the oxidation-reduction reaction of an electrochemical cell; the mass of an active electrode changes during the oxidation-reduction reactions

Question 9

Cell Potentials (E cell)

Answer 9

Difference in potential of the cathode and anode half-cells

Question 10

Standard Cell Potentials (E* cell)

Answer 10

The cell potential when all reactants and products are in their standard states (1 bar or 1 atm for gases; 1 M for solutes), usually at 298.15K

Question 11

Standard Hydrogen Electrode (SHE)

Answer 11

Half-cell based on hydrogen ion production, assigned a potential of exactly 0 V under standard state conditions, used as the universal reference for measuring electrode potential

Question 12

Electrode Potential (Ex)

Answer 12

The potential of a cell in which the half-cell of interest acts as a cathode when connected to the standard hydrogen electrode

Question 13

Standard Electrode Potential (E* x)

Answer 13

Electrode potential measured under standard conditions (1 bar or 1 atm for gases; 1 M for solutes) usually at 298.15K

Question 14

Faraday’s Constant

Answer 14

Charge on 1 mol of electrons; F = 96,485 C/mol e^-

Question 15

Nernst Equation

Answer 15

Relating the potential of a redox system to its composition

Question 16

Concentration Cell

Answer 16

Galvanic cell comprising half-cells of identical composition but for the concentration of one redox reactant or product

Question 17

Battery

Answer 17

Single or series of galvanic cells designed for use as a source of electrical power

Question 18

Primary Cells

Answer 18

Nonrechargeable battery, suitable for single use only

Question 19

Secondary Cells

Answer 19

Battery designed to allow recharging

Question 20

Dry Cell

Answer 20

Primary battery, also called a zinc-carbon battery, based on the spontaneous oxidation of zinc by manganese(IV)

Question 21

Alkaline Battery

Answer 21

Primary battery similar to a dry cell that uses an alkaline (often potassium hydroxide) electrolyte; designed to be an improved replacement for the dry cell, but with more energy storage and less electrolyte leakage than typical dry cell

Question 22

Nickel-Cadmium Cell

Answer 22

Rechargeable battery based on Ni/Cd half-cells with applications similar to those of lithium ion batteries

Question 23

Lithium Ion Batteries

Answer 23

Widely used rechargeable battery commonly used in portable electronic devices, based on lithium ion transfer between the anode and cathode

Question 24

Lead Acid Battery

Answer 24

Rechargeable battery commonly used in automobiles; it typically comprises six galvanic cells based on Pb half-reactions in acidic solution

Question 25

Fuel Cell (Flow Battery)

Answer 25

Devices similar to galvanic cells that require a continuous feed of redox reactants

Question 26

Corrosion

Answer 26

Degradation of metal via a natural electrochemical process

Question 27

Galvanization

Answer 27

Method of protecting iron or similar metals from corrosion by coating with a thin layer of more easily oxidized zinc

Question 28

Cathodic Protection

Answer 28

Approach to preventing corrosion of a metal object by connecting it to a sacrificial anode composed of a more readily oxidized metal

Question 29

Sacrificial Anodes

Answer 29

Electrode constructed from an easily oxidized metal, often magnesium or zinc, used to prevent corrosion of metal objects via cathodic protection

Question 30

Electrolytic Cell

Answer 30

Electrochemical cell in which an external source of electrical power is used to drive an otherwise nonspontaneous process

Question 31

Electrolysis