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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1985 edition. Excerpt:...the water of many thermal springs, therefore, may contain considerable concentrations of boron. Ocean water has 4.6 mg/L of boron, probably mostly in the form of undissociated boric acid. This compound has an appreciable vapor pressure at ordinary surface temperatures of the Earth, and some is vaporized into the air over the ocean as a result (Gast and Thompson, 1959). Boron is a contributor to the buffer capacity of the ocean and some other natural waters. Evaporite deposits of certain closed basins, especially in southeastern California, contain considerable amounts of boron and constitute ores from which boron salts are extracted. The common boron minerals are colemanite, CazBeOn-5iO, and kernite, Na2B4O7-4H2O. Sodium tetraborate (borax) is widely used as a cleaning aid and, hence, boron may be present in sewage and industrial wastes. The element has numerous industrial uses. Chemistry and Occurrence of Boron in Water Water analyses normally report boron concentrations in terms of elemental B, without attempting to define the actual species that are present. Boron forms an extensive series of complexes and polymeric ions. Hydroxide monomeric species include boric acid, H3BO3, which may also be written B(OH)3(aq), and its dissociation products. However, it is a weak acid and does not dissociate readily. The preferred value for the first dissociation constant is 10 924 (Bassett, 1980). This means that the uncharged ion predominates up to pH 9.24 and is the most likely form in most natural water. Polymeric hydroxide species of boron are not sufficiently stable to be significant in solutions containing less than 500 mg/L boron (as B) (Bassett, 1980). A series of fluoroborate complexes occurs in which all or part of the hydroxide in B(OH)i is...