There are many references to Nitrogen or Nitrate content. Can these two values be considered interchangeable when selecting a reagent for use in nitrate testing? Specifically Cobalt Chloride.
- Is the brucine-nitrate reaction specific to nitrate? Does brucine react similarly to either other anions, or to nitrogen-containing compounds in general?
- Is ACS-grade sulfuric acid sufficient for this test as-is (at 0.5ppm nitrate), or does it always need to be taken through the steps mentioned in the brucine sulfate reagent? (That is, what is considered “nitrate-free” in terms of ppm?)
- Is dry brucine or the brucine sulfate reagent sensitive to light, moisture, heat, or anything else that may degrade its performance?
- The monograph for cobalt chloride Nitrates test gives a different sample and control prep from that of the general chapter. This means that the blank solution, as prepped in the general chapter, will have a different amount of brucine sulfate reagent from the sample and control solutions. Should a modification be made to the blank solution to bring it in line with the sample and control solutions?