kyro8008
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Reactions of inorganic Nitrites
I have found lots of information regarding the manufacture of inorganic nitrites, but very little regarding their reactions. Everyone seems very
excited about them but I have no idea for their uses either.
Could anyone summerise the various reactions of nitrites (with water - does it ionise or react with water?, acids, bases, organics, etc).
What am i missing here...?
Thanks in advance!
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Nerro
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you could let KNO2 react with aniline to form K<sup>+</sup>C<sub>6</sub>H<sub>5</sub>-N=N<sup>-</sup>
So in other words, nitrite can react with amino groups to form diazonium salts and water.
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Microtek
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Or use them to make organic nitrites such as isopropylnitrite, then react this with hydrazine hydrate to form sodium azide.
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woelen
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In fact, nitrite is one of my favorite chemicals, because it allows many interesting experiments to be done. My favorites are simple but strange
inorganic compounds.
Just try the following:
Addition of NaNO2 or KNO2 to concentrated HCl: Formation of ONCl (nitrosyl chloride, an orange gas).
Addition of NaNO2 to dilute HCl, to which some NaBr or KBr is added. Formation of a deep chocolate brown compound (definitely not bromine, much
different color). Is this stuff ONBr?
Addition of NaNO2 to an acidified solution of NaSCN or NH4SCN gives a deep red/brown compound, probably nitrosyl isothiocyanate. Also formation of
intensely dense white fumes. I do not know the composition of all these. This really is a riddle.
Addition of NaNO2 to a solution of CuSO4 in dilute HCl gives rise to formation of a deep blue copper (II) complex. The nitrite, the chloride and the
acid are essential. Leave out one of them and you do not get the beautiful complex.
Addition of NaNO2 to a solution of CH3OH in dilute HCl or dilute H2SO4 gives a colorless gas, which burns with a white/grey flame. This gas is methyl
nitrite, CH3ONO, and can easily be isolated. This is an isomer of nitromethane, CH3NO2.
You can also make AgNO2 easily by mixing solutions of NaNO2 and AgNO3. This compound can be used in organic syntheses, e.g. making trinitromethane
from iodoform.
If you want more experiments with NaNO2, then look at my website under the experiments section and search for nitrite.
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neutrino
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Diazotization reactions come to mind. They are used to synthesize some expolsives, for example DDNP.
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kyro8008
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Thanks for all the responces, i will have to try these when I get hold of some nitrites.
Those experiments look very interesting!
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Darkblade48
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Be sure to keep the reaction flask cool (i.e. below 5 C) if you are planning to carry out diazotization
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garage chemist
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From diazonium salts you can make interesting products, like iodobenzene from aniline by diazotization and subsequent addition of potassium iodide
solution. There's a process in Gattermann- Wieland.
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roXefeller
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Regarding the diazotization with nitrites. How much is the reaction affected when the nitrite has degraded to have trace nitrates? I have a
container that's ten years old, which I use for curing, but I purchased straight nitrite so it could be useful in other things. Its been kept cool in
the basement but in HDPE plastic. I think its drawn in moisture, the crystals look deliquescent. Diazotization seems enigmatic as is so I'm not sure
the effect of nitrate. There is a smell of NOx too, though faint.
One must forego the self to attain total spiritual creaminess and avoid the chewy chunks of degradation.
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DraconicAcid
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Every time people talk about nitrites, I get that Boney M song stuck in my head. Nitrites to Venus, way out there in space....
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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GreenJames
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I saw a MrHomeScientist video in which he mixed a solution of ammonium chloride and sodium nitrite and heated this below boiling. This supposedly
forms elemental nitrogen which bubbles out of solution. This could be great for storing air-sensitive chemicals or just getting a sample of nitrogen
for an element collection.
https://youtu.be/xn82hcjR2tA
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