Concentration prediction:Before testing the water sample, first predict the fluoride value of the water sample, and select the operation steps corresponding to the range, e.g., predict the fluoride concentration value0-2mg/L, you need to select the operation procedure of 0-2mg/L range; If the fluoride concentration is expected to be 2-10mg/L, the procedure in the 2-10mg/L range is selectedSudden.
1. When the predicted value is in the range of 0-2L mg/L
If fluoride is present, the water sample will show a purple color, and the darker the water sample, the higher the concentration value. Analytical procedure: fluoride L; Watch out for overrange tips!
2. When the predicted value is in the range of 2-10mg/L
If fluoride is present, the water sample will show a purple color, and the darker the water sample, the higher the concentration value. Analytical procedure: fluoride H; Watch out for overrange tips!
3. When the predicted value exceeds 10mg /L
The water sample needs to be diluted to the corresponding concentration value in sections 1-2 above, and then operated according to the corresponding range, and the determination result is multiplied by the dilution factor.
4. Test steps on the computer
5. Precautions
◆ If there is fluoride, the water sample shows purple, and the darker the color, the higher the concentration value of the water sample.
◆ Pay attention to cross-contamination, use different measuring utensils for different liquids (pay attention to changing the tip when using a pipette).
◆ Use appropriate pipetting tools to take liquids, and large range measuring tools cannot measure small volumes of water samples, such as: 2mL pipettes cannot be used to remove 2mL and below liquidsFor liquids less than or equal to 2mL, it is recommended to pipette twice with a 1mL pipette.
◆ When using a pipette, it is necessary to calibrate the pipette frequently (it is recommended to do so once a week), and pay attention to replacing the tip during use.
