Sciencemadness Discussion Board

Ways to generate nitrogen dioxide(NO2)?

avi66 - 18-7-2010 at 05:39

I'm looking for effective way to generate nitrogen dioxide, i already try the hcl+kno3~hno3 + kcl to dissolve copper to copper nitrate and nitrogen dioxide... this isn't effective, because i lose i lose nitrogen dioxide to make the cu(no3)2 .... somebody know nitrate salt, which can i make from nitric acid... and will decompose to nitrogen dioxide in low temperature(100->250), and there is no problem to dry him .. at sun(not hygroscopic) ?

scimikey - 18-7-2010 at 05:53

You can heat equal amounts of potassium nitrate and sodiumbisulfate at pretty low temps to get NO2. I haven't tried this myself, but I think it was done successfully by one of the members here in a HNO3-thread.

Hoveland - 23-7-2010 at 00:47

Heating potassium nitrate and sodiumbisulfate would not only give off NO2, but also H2O and O2.

Suppose one wanted pure nitrogen dioxide that did not contain any diatomic oxygen?

For example, if one was attempting to make nitro-acetone, any oxygen would combine with the NO2 and the water produced to form nitric acid, which would lower the pH and ruin the reaction.

[Edited on 23-7-2010 by Hoveland]

psychokinetic - 23-7-2010 at 01:46

And suppose one wanted NO2 that did not contain any oxygen?

bbartlog - 23-7-2010 at 04:42

Copper or tin supposedly react with concentrated nitric acid to produce NO2 and water:

Cu + 4HNO3 → Cu(NO3)2 + 2NO2 + 2H2O (IIRC) or
Sn + 4HNO3 → H2O + H2SnO3 + 4 NO2 (if wikipedia is to be believed)

Sedit - 23-7-2010 at 05:20

Potassium nitrate + Sodium Metabisulfite + H2SO4 has been producing ALOT of NOx fumes in recent experiments iv been running. I can not vouch for the purity but I do know the fumes are denser then any I have ever seen.

[edited for correctness]
Thank you for spotting that hoveland.

[Edited on 23-7-2010 by Sedit]

franklyn - 23-7-2010 at 12:14

Surprisingly this has been addressed before ,

Set up a drip of strong Hydrochloric acid onto Sodium nitrite.

Given this is the Beginnings section I have misgivings about citing this.

Experimental & UNTESTED

OBSERVE safety precautions. At least one visitor here did not _


Engager - 3-8-2010 at 18:19

Another common ways to generate lots of NOx is to use reaction of nitric acid with starch, or sodium nitrite with sulphuric acid.

starman - 3-8-2010 at 22:37

There's a book available in the library that contains all you'll ever need to know about the generation of various combinations of NOx.I have found calcium nitrite(OTC corrosion inhibitor) and HCl very effective.

peach - 4-8-2010 at 02:36

I don't know if I'm behind the thread here but NurdRage on youtube has a few videos all about doing this, specifically using it to make nitric acid.


Jor - 4-8-2010 at 03:05

If you need small amounts of dry, pure NO2, you can heat lead nitrate, wich decomposes at low temperatures to give NO2, O2 and PbO (wich can be converted back to lead nitrate).

woelen - 4-8-2010 at 04:49

The NO2 you get from that process indeed is dry, but not pure. It is mixed with O2. In many reactions that is not a problem, but in some reactions it may be a problem.

Btw, the reaction with Pb(NO3)2 is not as smooth as one would desire. I have Pb(NO3)2, consisting of crystals at the size of around 1 mm. When I heat this, then nothing happens for a while and then suddenty a very violent reaction occurs, accompanied with strong crackling noise, sometimes even loud bangs, and crystals being lounched from the crucible at very high speeds. Not pleasant at all. You can moderate the reaction somewhat by crushing the Pb(NO3)2 to dust and mixing this with fine dry sand. When this mix is heated, then the reaction proceeds more smoothly.

Random - 16-8-2010 at 13:50

You need to mix HCl, nitrate salt and copper metal to make NO2.

BromicAcid - 16-8-2010 at 17:28

NO<sub>2</sub> mixed with O<sub>2</sub>? If it's an issue why not collect the nitrogen dioxide, it's plenty easy to condense. Excess oxygen should refuse to collect and leave the apparatus.