Abstract
The formation of 10750oxy-apatite may be a major determinant of the concentration of dissolved orthophosphate in many natural hard fresh waters. Tests of this hypothesis require knowledge of the precision and accuracy of the calculated ionic product [Ca2+]5 [PO sup3−inf4 ]3 [OH−]. In routine analyses the largest contribution to overall error is probably that of pH: precision and bias better than 0.02 units are desirable. There is also a large uncertainty present in the possible bias of the third ionisation ‘constant’ of ortho-phosphoric acid.
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Clymo, R.S., Golterman, H.L. Precision and accuracy of the determination of the ionic product of 10750oxy-apatite. Hydrobiologia 126, 31–34 (1985). https://doi.org/10.1007/BF00008384
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DOI: https://doi.org/10.1007/BF00008384