woelen - 10-6-2016 at 13:29
I did a little experiment, wondering how ClO2 and NO/NO2 would interact with each other. The result of this experiment is impressive and spectacular.
I mixed two oxidizing compunds, both fine crystalline powder, dry. One of them is sodium nitrite, NaNO2, and the other is sodium chlorite, NaClO2.
When the powders are mixed, nothing happens.
To the mix, I added a small quantity of dilute sulphuric acid (appr. 20% by weight). When this is done, you get an impressive crackling noise,
followed by an explosion 
I only used small quantities (appr. 100 mg of each chemical).
With NaNO2 alone, there is fizzling and you get a lot of NO/NO2. With NaClO2 alone, the liquid turns deep yellow and slowly some yellow gas escapes
from the liquid, without fizzling.
What is remarkable on this is that both compounds are strong oxidizers and despite of both of them being oxidizers, a mix of them, when acidified,
gives an extremely violent reaction. Normally, a reductor/oxidizer mix gives violent reactions in certain cases, here it is an oxidizer/oxidizer mix.
I have the impression that chlorite or HClO2 (at low pH) reacts very exothermically with nitrite (or HNO2 at low pH) to form the strong acids HCl and
HNO3. This leads to formation of more (stronger) acid, allowing conversion of more nitrite and chlorite to their respective acids HNO2 and HClO2,
which again can react. Besides that, HClO2 and HCl give lots of ClO2 and this also may react violently with HNO2.
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I also did a simple test. Add some solid NaClO2 to dilute (10%) H2SO4. When this is done, the solid dissolves and the liquid turns deep yellow, due to
formation of ClO2. The acid HClO2 disproportionates to ClO2 and HCl, it is unstable. When some sodium nitrite is added to this yellow liquid, then
quickly all ClO2 reacts and the liquid becomes colorless and also becomes warm. So, nitrite (or HNO2) reacts quickly with ClO2.
If you have both NaNO2 and NaClO2, it is nice to repeat this experiment, but please be careful. DO NOT SCALE UP THE EXPERIMENT. Use 100 mg quantities,
not more!
[Edited on 11-6-16 by woelen]
nitro-genes - 10-6-2016 at 14:08
Do hypochlorites show a similar reaction with nitrites under acidic conditions? Was thinking maybe a nitrosylchlorite or nitrosylhypochlorite is the
explosive compound here as they presumably could rearrange very quickly into more stable products.
Sulaiman - 10-6-2016 at 14:34
"I also did a simple test. Add some solid NaNO2 to dilute (10%) H2SO4. When this is done, the solid dissolves and the liquid turns deep yellow, due to
formation of ClO2." ???
NaClO2 ?
Edit(woelen): Indeed. I corrected my mistake.
[Edited on 11-6-16 by woelen]
blogfast25 - 10-6-2016 at 17:54
Best also to avoid any organic contamination, when carrying out this type of experiment. Clean glassware, please!
deltaH - 11-6-2016 at 04:48
Reactions like this might be faintly luminescent because of the formation of excited radicals.
Care to add the mix, turn off the lights completely and then open the apperature of a camera completely and see if you capture a glowing test tube?
[Edited on 11-6-2016 by deltaH]
PHILOU Zrealone - 12-6-2016 at 07:02
ClO2 or Cl2O may explode in contact with reducers what N=O and NO2 are...since not at their maximum oxydation state.
I suppose the following is happening:
ClO2 + NO --> NO2 + N2O5 + Cl2
ClO2 + NO --> NO2 + O2 + Cl2
ClO2 + NO2 --> N2O5 + Cl2
Cl2O + NO --> NO2 + N2O5 + Cl2
Cl2O + NO --> NO2 + O2 + Cl2
Cl2O + NO2 --> N2O5 + Cl2
One may consider transcient explosive mixed anhydrides
O=N-O-Cl=O
O=N-O-ClO2
O2N-O-Cl=O
O2N-O-ClO2
For sure a good finding for the energetic field.
[Edited on 12-6-2016 by PHILOU Zrealone]