Electrochemistry

Vocabulary

anode

electrode where the oxidation half-reaction takes place

battery

galvanic cell in which the electrical work is used as a source of electrical power

cathode

electrode where the reduction half-reaction takes place

cathodic protection

method of protecting a metal by sacrificing another metal as an anode in a galvanic cell

circuit

path through which electrons flow

corrosion

process by which metals oxidize and return from a reduced form to their natural oxidation state

dry cell

galvanic cell in which the electrolytes exist as pastes

electric current

flow of electric charge

electric potential

amount of work required to move one charged particle from one point to another

electrical work

voltage between two points when a charged particle is moved between them

electrochemistry

branch of science that studies chemical reactions that cause electrons to move, resulting in the transfer of electrical charge

electrode

electrical conductor through which current enters or leaves an electrochemical cell

electrolysis

process of using electric current to do work on a chemical cell against its electric potential

electrolyte

ionic solution that can be decomposed by electricity

electrolytic cell

electrochemical cell that requires electrical energy to drive a nonspontaneous redox reaction

Faraday constant

charge of one mole of electrons (96,485 C/mol)

fuel cell

device that generates electrical power through the ionization of hydrogen or another molecule

galvanic cell

electrochemical cell formed when metal strips connected by a wire are immersed in different solutions of a redox reaction and the solutions are connected by a salt bridge

galvanic cell notation

shorthand method of describing the setup of a galvanic cell

galvanization

process that coats a metal with zinc as a sacrificial anode

inert electrode

electrode that does not take part in a chemical reaction but serves only to transfer electrons

Nernst equation

equation used to find the cell potential under conditions that are not standard, given as E=ERTnFlnQE=E^\circ-\frac{RT}{nF}\ln Q

oxidation half-reaction

half-reaction showing oxidation (electron loss) of a species

reduction half-reaction

half-reaction showing reduction (electron gain) of a species

sacrificial anode

anode made of a metal coupled to a more valuable metal, which it protects as part of a galvanic cell that undergoes galvanic corrosion

salt bridge

inert connection between the two half-cells, composed of either a glass tube filled with an inert salt solution or a strip of filter paper soaked in an inert salt solution, that transfers ions between the half-cells

standard cell potential

potential difference between the cathode and the anode under standard conditions

standard hydrogen electrode (SHE)

platinum electrode in 1 M H+(aq) solution with bubbled hydrogen gas at 1 atm of pressure

standard reduction potential (E°)

tendency of the species to be reduced under standard conditions