UPSC Combined Geo-Scientist, Mains · 2019 · Mains Paper III
Q3(a). Potentiometric fluoride measurement
Question
Describe potentiometric determination of fluoride in water.
Answer in brief
Use a calibrated fluoride-selective LaF₃ membrane electrode with a reference electrode and controlled solution conditions.
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CoversPotentiometric fluoride measurementIon-selective electrodes
All parts of Question 3
- 3(a) Potentiometric fluoride measurement10 marks
- 3(b) Isoelectric and isoionic points5 marks
- 3(c) Identifying and balancing redox5 marks
- 3(d) Errors from coprecipitation5 marks
- 3(e) Heavy-metal adsorption on hydrous oxides5 marks