MeshPL
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Test for nitrite
Hello everybody!
I was wondering if any of you know a good test to detect small amount of nitrites in presence of:
-some alcohol (traces)
-a lot of nitrates
-little fluoride
-some metal ions (Pb, Cu, Ni, little Na)
-highly acidic pH (around 1)
Thre were some nice tests, like thiourea + iron (III), sulphamic acid + barium, azo coupling, indole nitrosylation but I'm not sure if they will be
good for those conditions. Also indole or reagents for azo coupling are hard to get.
[Edited on 23-2-2016 by MeshPL]
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UC235
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Nitrous acid has a pKa of 3.4 so anything more acidic than that is going to get you HONO from nitrites and it decomposes quite readily.
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MeshPL
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Yea, but I'm pretty sure traces will remain I think, and I want to detect those traces.
Unless, you say, that there will be no detectable traces, than I may give that up.
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nezza
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Azo coupling should work and is likely to be quick, easy and sensitive.
If you're not part of the solution, you're part of the precipitate.
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woelen
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Add some thiocyanate salt. You obtain some nitrosyl thiocyanate, which is very dark brown in aqueous solution and slowly decomposes. This reaction is
quite sensitive.
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