Page 61 - Pharmaceutical Analytical Chemistry II - Pharm D- 02-06-07102
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Do not store the pH electrode in distilled water.
Potentiometric Determination of Fluoride
We have already known about one type of ion selective electrode
which selectively measures the amount of H3O+ in solution9 pH
meter). There are several other types of ion selective electrodes,
including the one which measures the fluoride ion concentration.
Purpose: To determine the amount of fluoride ion in samples of
toothpaste, mouthwash, and tap water.
- Acetate buffer of pH 5.25 is used to adjust the pH. The potential
of the standard and sample solutions is measured using the
fluoride ion selective electrode.
- The concentration of fluoride is determined using standard
addition or serial dilution (calibration) method.
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