The following sections of this BookRags Literature Study Guide is offprint from Gale's For Students Series: Presenting Analysis, Context, and Criticism on Commonly Studied Works: Introduction, Author Biography, Plot Summary, Characters, Themes, Style, Historical Context, Critical Overview, Criticism and Critical Essays, Media Adaptations, Topics for Further Study, Compare & Contrast, What Do I Read Next?, For Further Study, and Sources.
(c)1998-2002; (c)2002 by Gale. Gale is an imprint of The Gale Group, Inc., a division of Thomson Learning, Inc. Gale and Design and Thomson Learning are trademarks used herein under license.
The following sections, if they exist, are offprint from Beacham's Encyclopedia of Popular Fiction: "Social Concerns", "Thematic Overview", "Techniques", "Literary Precedents", "Key Questions", "Related Titles", "Adaptations", "Related Web Sites". (c)1994-2005, by Walton Beacham.
The following sections, if they exist, are offprint from Beacham's Guide to Literature for Young Adults: "About the Author", "Overview", "Setting", "Literary Qualities", "Social Sensitivity", "Topics for Discussion", "Ideas for Reports and Papers". (c)1994-2005, by Walton Beacham.
All other sections in this Literature Study Guide are owned and copyrighted by BookRags, Inc.
A measure of the oxidation/reduction status of a natural water, sediment or soil. It is a relative electrical potential, measured with a potentiometer (e.g., a pH meter adjusted to read in volts) using an inert platinum electrode and a reference electrode (calomel or silver/silver chloride). EH is reported in volts or millivolts, and is referenced to the potential for the oxidation of hydrogen gas to hydrogen ions (H+). This electron transfer reaction is assigned a potential of zero on the relative potential scale. The oxidation and reduction reactions in natural systems are pH dependent and the interpretation of EH values requires a knowledge of the pH. At pH 7, the EH in water in equilibrium with the oxygen in air is +0.76v. The lowest possible potential is 0.4v when oxygen and other electron acceptors are depleted and methane, carbon dioxide, and hydrogen gas are produced by the decay of organic matter.