Introduction to Electrochemistry

Electrochemistry  -  The study of the exchange between electrical and chemical energy.

Battery  -  A galvanic cell or cells connected in series with a constant amount of reagents. A battery stores energy in the form of electrical potential energy.

Electrorefining  -  Process by which materials, usually metals, are purified by means of an electrolytic cell. The anode is the impure metal and the cathode is a very pure sample of the metal.

Oxidation  -  The loss of an electron from a species (an increase in its oxidation number).

Oxidation Number  -  A conceptual bookkeeping numbering system that allows us to track the number electrons transferred during a redox reaction. The rules for determining the oxidation number of a species are discussed in Galvanic Cells.

Reduction  -  The gain of an electron by a species (a decrease in oxidation number).

Redox  -  A reaction involving the transfer of one or more electrons from the reducing agent to the oxidizing agent.

Reducing Agent  -  A reactant in a redox reaction that donates an electron to the reduced species. The reducing agent is oxidized.

Oxidizing Agent  -  A reactant in a redox reaction that accepts an electron from the oxidized species. The oxidizing agent is reduced.

Galvanic Cell  -  An electrochemical cell with a positive cell potential that allows chemical energy to be converted into electrical energy.

Cell Potential  -  The overall electrical potential of an electrochemical cell. It is the sum of the reduction potential of the cathode and the oxidation potential of the anode.

Oxidation Potential  -  The potential of a half-reaction written as an oxidation reaction, it is the opposite sign of the same reaction written as a reduction.

Reduction Potential  -  Arbitrarily setting the potential of the standard hydrogen electrode, SHE, discussed in Galvanic Cells, to zero, all other half reactions are measured by their power to reduce hydrogen. The voltage given by the construction of a galvanic cell between the SHE and the reduction of interest gives the standard reduction potential of that reduction.

Work  -  Force over a distance.

Electrolytic Cell  -  A cell that consumes electrical energy to drive a non-spontaneous redox reaction.