Download Electro Chemistry

Electro Chemistry
The study of chemical reactions that convert chemical energy into electrical energy
Electrochemical Cell – a device that continually converts chemical energy to electrical energy
(ie: batteries)
Parts:
1.
2.
Electrodes (2): Solid electrical conductors connected in some manner where the
redox reaction occurs. Allows for metallic conduction (flow of electrons)
Electrolyte: an aqueous solution (or paste) that the electrodes are immersed in.
Allows for electrolytic conduction (flow of ions)
For the cell to function properly it must be connected externally (ie: electrodes must be
connected) and internally (to allow the flow of ions). If the electrodes are in two different
electrolytes a salt bridge is used to link the two half cells.
Salt bridges – contain a salt solution and allows the ions to move to the other container in
order to maintain the electrical neutrality of the solutions (most commonly an ion, nitrates)
aka NaNO3 or KNO3
Electron Flow in a Cell –
 In every electrochemical cell oxidation occurs at the Anode and
reduction occurs at the Cathode.
 As a result of electrons flow form the ANODE to the CATHODE in
every cell.
 The force pushing the electrons around the cell is the potential
difference or electromotive force that exists between the two electrodes
(aka VOLTAGE)
 The rate at which the electrons flow is the current
Types of Electrochemical Cells: There are 2 types of electrochemical cells: Galvanic and
Electrolytic.