Sciencemadness Discussion Board

how to purify the NaNO3?

OneShot - 24-3-2011 at 11:27

how to purify the NaNO3? I did, this method NaNO3 ----> 80 g NH4NO3 + 40 gr NaOH = NaNO3 + NH4OH


I did, this method, but never properly cleanse help me that I put reagents tried for crystallization but NaNO3 is not done through this process


thaks!

[Edited on 24-3-2011 by OneShot]

[Edited on 24-3-2011 by OneShot]

mr.crow - 24-3-2011 at 11:39

I have done this reaction. Make sure you filter the junk out of the ammonium nitrate solution first. Watch out for all the ammonia gas too, yuck!

Crystallization works great. Just boil off some water, cool, filter crystals and repeat. You have to boil down the solution several times to get it all out. You want the crystals to form while cooling not when its still boiling. Put in make-shift desiccator for a few weeks. Much larger crystals than KNO3.

180g/100mL at 100 degrees
73g/100mL at 0 degrees

Mixell - 24-3-2011 at 13:56

Because NH4OH cannot be isolated, boiling a solution of this substance will result in water vapors and gaseous ammonia.
So I assume boiling a solution of NaNO3 and NH3(aq) will result in solid NaNO3 (just don't over heat it) and perform the boiling outside or in a fume hood.

OneShot - 24-3-2011 at 19:20

you guys did not understand, is not to purify and to solidify was wondering how I withdraw the excess NaOH and NH4NO3 who remained in solution without reacting!


[Edited on 25-3-2011 by OneShot]

Sedit - 24-3-2011 at 20:11

Sorry man but we are not understanding because your english is, to put it bluntly, terrible. I have had trouble understanding simple sentances you have written so if you could, please put a little more effort into expressing you post in a more understandable means.

If you are worried about unreacted material then understand NaOH solubility is huge. So what you want to do is add the correct molar ratios of NaOH and Ammonium Nitrate with a SLIGHT excess of NaOH.

As you crystalize it as other have mentioned your excess NaOH will remain in solution. Your Ammonium Nitrate will be fully reacted and no longer exist at all so there would be no concern there.