Aqueous Ammonia Equilibrium Calculations: Effect of pH and Temperature
01 Dec 1975-Wsq: Women's Studies Quarterly (NRC Research Press Ottawa, Canada)-Vol. 32, Iss: 12, pp 2379-2383
TL;DR: A critical evaluation of the literature data on the ammonia–water equilibrium system has been carried out and results of calculations of values of pKa at different temperatures and of percent of NH3 in aqueous ammonia solutions of zero salinity as a function of pH and temperature are presented.
Abstract: The toxicity of ammonia to fishes has been attributed to the un-ionized ammonia chemical species present in aqueous solution Because the percent of total ammonia present as un-ionized ammonia (NH3) is so dependent upon pH and temperature, an exact understanding of the aqueous ammonia equilibrium is important for toxicity studies A critical evaluation of the literature data on the ammonia–water equilibrium system has been carried out Results of calculations of values of pKa at different temperatures and of percent of NH3 in aqueous ammonia solutions of zero salinity as a function of pH and temperature are presented
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Cites background from "Aqueous Ammonia Equilibrium Calcula..."
...The relative concentration of each form is strongly dependent on pH and to a lesser extent on temperature, and salinity has only a minor influence (Whitfield, 1974; Emerson et al., 1975; Bower and Bidwell, 1978; Spotte and Adams, 1983)....
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...The relative concentration of each form is strongly dependent on pH and to a lesser extent on temperature, and salinity has only a minor influence (Whitfield, 1974; Emerson et al., 1975; Bower and Bidwell, 1978; Spotte and Adams, 1983)....
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References
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165 citations
TL;DR: In this article, it was shown that the un-ionized ammonia molecule and not the ammonium ion is the form of the toxicant harmful to fish, and the amount of unionised ammonia in the water was quantified.
Abstract: Previous studies have shown that the un-ionized ammonia molecule and not the ammonium ion is the form of the toxicant harmful to fish. Prior attempts to quantify the amount of un-ionized ammonia in...
151 citations
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