AP Chemistry: Chapter 21

REDOX reaction

a chemical reaction in which one species looses electrons and the other gains said electrons

oxidation

a species loosing electrons

reduction

a species gaining electrons

oxidizing agent

the species being reduced

reduction agent

the species being oxidized

voltaic / galvanic cell

a spontaneous REDOX reaction (batteries)

electrolytic cell

an electrochemical cell that drives a non-spontaneous reaction using an external power source to seperate elements

anode

the cell where oxidation occurs and mass is lost

cathode

a cell where reduction occurs and mass is gained

salt bridge

a non-reactive electrolyte solution that connects the two half cells and maintains their neutrality

how does the salt bridge work?

charge builds at the cathode and anode and as the reaction progresses, the spectator ions in the salt bridge neutralize the charges

active electrode

an electrode that is within the reaction

inactive electrode

an electrode that isn’t apart of the reaction

what are inactive electrodes used for?

some reactions don’t have solids so inactive electrodes allow the reaction to progress

what are two inactive electrodes?

graphite and platinum