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Alkalinity - "The capacity of water for neutralizing an acid solution." - U.S. Geological Survey, 2010

Alaklinity - "Alkalinity is the acid neutralizing capacity of solutes in a water sample, reported in milliequivalents per liter. Alkalinity consists of the sum of titratable carbonate and noncarbonate chemical species in a filtered water sample." - Rounds, 2006

Alkalinity - "The capacity of a water to accept protons, i.e., hydrogen ions. It is usually expressed as milliequivalents per liter." - American Geological Institute, 1976

Alkalinity - "Alkalinity and acidity are then capacity factors that represent, respectively, the acid- and base-neutralizing capacities (ANC and BNC) of an aqueous system. For solutions that contain no protolysis system other than that of aqueous carbonate, alkalinity is a measure of the quantity of strong acid per liter required to attain a pH equal to that of a CT molar solution of Na2CO3....Thus alkalinity and acidity are convenient measures for estimating the maximum capacity of a natural base to neutralize acidic and caustic wastes without permitting extreme disturbance." - Stumm and Morgan, 1981

Related Definitions

Acid Neutralizing Capacity (ANC) - "ANC is the acid-neutralizing capacity of solutes plus particulates in an unfiltered water sample, reported in milliequivalents or microequivalents per liter." - Rounds, 2006

USGS Information on Alkalinity


American Geological Institute, 1976, Dictionary of geological terms (4 ed.): Garden City, New York, Anchor Press, 472 p.

Rounds, S.A., 2006, Alkalinity and acid neutralizing capacity, in Techniques of Water-Resources Investigations (3 ed.): U.S. Geological Survey, Book 9, Chapter A6, Section 6.6.

Stumm, W. and Morgan, J.J., 1981, Aquatic chemistry--An introduction emphasizing chemical equilibria in natural waters (2 ed.): New York, New York, John Wiley and Sons, Inc., 780 p.

U.S. Geological Survey, 2010, Water science glossary of terms: U.S. Geological Survey, access date August 5, 2010. 


Disclaimer: The definitions on this page are provided for information purposes only, and do not indicate endorment by the U.S. Geological Survey.

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