Hach Polymetron 9611sc PO43-LR Operation Manual page 8

Standard preparation
Prepare stock solution
Use this procedure to make a 1 g/L phosphate stock solution. Use the stock solution to make the
standard solution. If the stock solution is kept at 5 °C (41 °F), the shelf life is approximately one year.
Be sure to clean all labware before use. Items to collect:
• Sodium phosphate monobasic, NaH
• Laboratory scale
• Laboratory oven
• Desiccator
• Volumetric flask, 1 L
• Deionized water, 2 L
1. Put approximately 1.5 g of the sodium phosphate monobasic in a 100 °C oven for 24 hours.
2. Put the sodium phosphate monobasic in a desiccator for one hour.
3. Add approximately half of the deionized water to the volumetric flask.
4. Weigh 1.26 g of the dried sodium phosphate monobasic. Stir the water and add the sodium
phosphate monobasic to the volumetric flask.
5. Stir the solution until the reagent fully dissolves.
6. Dilute to the mark with deionized water. Mix fully.
Prepare Standard 1
Use deionized water that has a resistivity of 18.2 MΩ-cm for the zero-standard solution. Add the
solution to Analyzer Bottle #S1.
Prepare Standard 2
Use this procedure to make a 3 mg/L phosphate standard solution. Be sure to clean all labware
before use.
Items to collect:
• Phosphate stock solution, 1 g/L as PO
• Volumetric flask, 2 L
• Pipet, 6 mL
• Deionized water, 2 L
• Analyzer Bottle #S2
1. Add approximately half of the deionized water to the volumetric flask. Add 6 mL of the 1 g/L
standard solution.
2. Dilute to the mark with deionized water. Mix fully.
3. Add the solution to the analyzer bottle. Insert the seal assembly and put the cap on.
Turn on the analyzer
1. Open the top door.
2. Pull the analytics panel open. A magnetic latch holds the panel closed.
3. Turn on the power switch on the main circuit board (refer to
4. Close the analytics panel.
8 English
PO , 99%, analytical grade, 1.26 g
2 4
4
Figure 4 on page 6).