A modified single solution method for the determination of phosphate in natural waters
Abstract
A single solution reagent is described for the determination of phosphorus in sea water. It consists of an acidified solution of ammonium molybdate containing ascorbic acid and a small amount of antimony. This reagent reacts rapidly with phosphate ion yielding a blue-purple compound which contains antimony and phosphorus in a 1:1 atomic ratio. The complex is very stable and obeys Beer's law up to a phosphate concentration of at least 2 μg/ml.The sensitivity of the procedure is comparable with that of the stannous chloride method. The salt error is less than 1 %.
Résumé
Une méthode spectrophotométrique est décrite pour le dosage du phosphate dans l'eau de mer, an moyen de molybdate d'ammonium, en présence d'acide ascorbique et d'antimoinc. Il se forme rapidement un composé violet bleu, renfermant antimoine et phosphore dans un rapport atomique de 1:1.
Zusammenfassung
Beschreibung einer Methode zur Bestimmung von Phosphat in Mecrwasser mit Hilfe von Ammoniummolybdat in Gegenwart von Ascorbinsäure und Antimon. Der gebildete blau-violette Komplex wird spektrophotometrisch gemessen.
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