Hey guys, I made soma yellow aqua regia using hydrochloric acid and con nitric acid. That worked well and then I decided to test its potency by
placing some aluminum within a beaker of it. I expected the reaction to be similar to aluminum and hydrochloric acid. (Producing a small amount of
hydrogen gas) so, I left the lid of the barker ajar to prevent hydrogen buildup and set a rag on top to absorb any hydrogen. Things did not go
according to plan. The reaction was much more vigorous than anticipated. I first noticed something was wrong about 3 minutes later when my eyes began
to water. I ran across the room and noticed that instead of bubbling it was fucking foaming. I ran into the bathroom and dumped it down the sink while
diluting it with water. Since my room lacks a proper fume hood I opened my door, turned the fan on, and placed a towl over my tortoises tank. So in
conclusion I have a few questions.
Is the idea of putting a rag over a mixture to absorb fumes affective with less vigorous reactions?
Is there anything I should have done differently?
What the fuck was I exposed to? I don't think it was hydrogen.
[Edited on 15-12-2014 by scrubs2009]DraconicAcid - 14-12-2014 at 19:39
Aqua regia is hydrochloric acid and nitric acid. Mixing sulphuric acid and nitric acid is good for nitration of organic compounds, but it's not aqua
regia.
Reacting this mixture with reducing agents (such as aluminum) is not going to give you hydrogen gas, because the nitrate ion is a stronger oxidizing
agent than hydrogen ions. You will get nitrogen monoxide or nitrogen dioxide given off, generally.
If you want to test the potency of an acid mixture, test it with something that's a weaker reducing agent- seeing if it's potent enough to react with
aluminum is like checking to see if your hammer is heavy enough to smash a mosquito.scrubs2009 - 14-12-2014 at 19:43
Sorry typo. I did use hydrochloric acid. subsecret - 14-12-2014 at 20:43
You've likely inhaled a little bit of hydrogen, nitrogen dioxide, and acid vapors. I'd say you'll be just fine, but keep in mind that I'm not a
doctor. Common sense dictates that if you feel like crap, you should go to the doctor.
This is coming from someone who is exposed to HCl fumes A LOT, nitric acid fumes occasionally, and sometimes NO2 and halogens. I've never been
bothered by any of them, really.
DraconicAcid makes a good point. Your aluminum is oxidized way to easily to test the "potency" of aqua regia. Copper might be a
better choice, or gold, if you're wealthy. Just be sure to work outside in the future.
Edit: Typos.
[Edited on 15-12-2014 by Awesomeness]scrubs2009 - 14-12-2014 at 21:13
Thanks for all the help, although I'm still curious if putting a rag over a container that is emitting gas is a good idea. This keeps the gas from
building up and is instead absorbed by the rag.
Like all good chemists I have a special rag for lab use. I call mine my science rag...or sometimes Kevin.gdflp - 14-12-2014 at 21:18
Although I could be wrong, I don't think a rag will do much in most situations. I wouldn't think that a rag could absorb much gas. I can even think
of situations where a rag would burst into flames. I would instead recommend a tube leading off to a beaker with a scrubbing solution, NaOH works
well with acidic fumes, HCl or H2SO4 for basic fumes, and NaHSO3 or NaOH for halogens.DraconicAcid - 14-12-2014 at 21:26
A wet rag may absorb some gases (hydrochloric acid vapours, nitrogen dioxide), but won't do anything to hydrogen or carbon monoxide. gdflp's
suggestion of a scrubbing solution is a much better idea.Zyklon-A - 14-12-2014 at 21:26
The rag would be good to keep aerosols from floating around your lab and coating crap with the very corrosive solution. But stopping a gas with a rag
is like trying to catch plankton with a fishing net.dermolotov - 15-12-2014 at 14:26
A wet rag may absorb some gases (hydrochloric acid vapours, nitrogen dioxide), but won't do anything to hydrogen or carbon monoxide. gdflp's
suggestion of a scrubbing solution is a much better idea.
why not just set up a bubbler solution? Whenever I distil chloroform, I set up a small little beaker of DCM and seal off the entire distillation set
with the only escape being a silicon tube bubbling in a solution of DCM.
If you want to capture HCl, just make a caustic solution. If you want to capture NO2, same thing. If you want to capture CO, use something that will
capture it and make a carbonyl ligand with it. I would suggest HCO3 but you need to find some salt that won't react with the previous caustic
solution.
