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Updated: Jun 28, 2026

Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies
Published on: July 1, 2016
Gradient flow titration for the determination of fluoride ion in natural waters
A C Lopes da Conceição1, M M Correia dos Santos, M L Simões Gonçalves
1Instituto Superior Técnico, Centro de Quimica Estrutural, Av. Rovisco Pais, Lisbon, Portugal. pcqaclc@alfa.ist.utl.pt
Abstract:
The determination of fluoride ions in water samples was accomplished by using a gradient flow titration. A standard commercial combined electrode is used in a cell configuration that combines the gradient chamber and the electrode in a single unit. The methodology developed gives results with a relative standard deviation of about 3%. The average recoveries after spiking natural samples with fluoride are in the range 100-102%. The method was used successful in determining the fluoride concentration in water samples.
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