1 minute read

Coulomb

Electrolytic Cells

The coulomb (as a unit) can be thought of in another way, as given by the following equation: 1 coulomb = 1 ampere X 1 second. The ampere (amp) is the metric unit used for the measurement of electrical current. Most people know that electrical appliances in their home operate on a certain number of "amps." The ampere is defined as the flow of electrical charge per second of time. Thus, if one multiplies the number of amps times the number of seconds, the total electrical charge (number of coulombs) can be calculated.

This information is of significance in the field of electrochemistry because of a discovery made by the British scientist Michael Faraday in about 1833. Faraday discovered that a given quantity of electrical charge passing through an electrolytic cell will cause a given amount of chemical change in that cell. For example, if one mole of electrons flows through a cell containing copper ions, one mole of copper will be deposited on the cathode of that cell. The Faraday relationship is fundamental to the practical operation of many kinds of electrolytic cells.

See also Electric charge.


Resources

Books

Brady, James E., and John R. Holum. Fundamentals of Chemistry. 2nd edition. New York: John Wiley and Sons, 1984.

Holton, Gerald, and Duane H. D. Roller. Foundations of Modern Physical Science. Reading, MA: Addison-Wesley Publishing Company, 1958.

Shamos, Morris H., ed. Great Experiments in Physics. New York: Holt, Rinehart and Winston, 1959.

Wilson, Jerry D. Physics: Concepts and Applications. 2nd edition. Lexington, MA: D. C. Heath and Company, 1981.


David E. Newton

KEY TERMS

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Electrolytic cell

—An electrochemical cell in which an electrical current is used to bring about a chemical change.

Inverse square law

—A scientific law that describes any situation in which a force decreases as the square of the distance between any two objects.

Magnetic pole

—Either of the two regions within a magnetic object where the magnetic force appears to be concentrated.

Proportionality constant

—A number that is introduced into a proportionality expression in order to make it into an equality.

Qualitative

—Any measurement in which numerical values are not considered.

Quantitative

—Any type of measurement that involves a mathematical measurement.

Torsion

—A twisting force.

Additional topics

Science EncyclopediaScience & Philosophy: Cosine to Cyano groupCoulomb - History, Coulomb's Law, Applications, Electrolytic Cells