2106169 NitraVer 5 Nitrate Reagent Powder Pillows, 0.1-30.0 mg/L NO₃-N

Article 2106169 measures mid-range nitrate 0.1-10.0 mg/L NO₃-N and high range nitrate 0.3-30.0 mg/L NO₃-N in water, wastewater and seawater. The product uses Cadmium Reduction method (8039 - HR, 8171 - MR). Each package can be used for 100 tests. The product can be evaluated using all Hach spectrophotometers except DR2000, DR2010 and DR3000. NitraVer 5 Nitrate Reagent Powder Pillows may be used for 10mL sample analysis.

Before you start take into account the following:

• Collect the sample in clean glass or plastic containers.
• Take into consideration that shaking time and technique affect the color development.
• Use standard solution within the test range, run the test several times and use the adjusted shaking time for sample measurements.
• Correct the testing results for the dilution caused by the volume additions. 

Procedure for NO₃-N measurement

Start program 353 N, Nitrate MR PP to perform mid-range nitrate determination. Select program 355 N, Nitrate HR PP to evaluate high range nitrate. Mix 10mL of sample and NitraVer 5 Nitrate Reagent Powder Pillow in the cell. After that install the stopper and shake the sample cell for 1 minute. After 5 minutes, fill another cell with 10 mL of sample to prepare the blank. Clean the blank cell, insert the instrument and select ZERO. Finally, clean the pretreated sample cell, install into the cell holder and press READ.

Summary of method

Cadmium metal reduces nitrate in the sample to nitrite. The nitrite ion enters into reaction in an acidic medium with sulfanilic acid forming an intermediate diazonium salt that couples with gentisic acid forming an amber colored solution.

Sample preparation

Filter the collected sample and store at or below 6 °C (43 °F) for short-term conservation of the sample (up to 48 hours). Adjust the sample pH to 2 or less with concentrated sulfuric acid and keep at or below 6 °C (43 °F) for long-term conservation of the sample (for a maximum of 28 days).