raiden
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The actual risk of nitric acid.
Hello everyone. Just a quick question.
I recently ordered a 20L drum of 68% nitric acid from a chemical supplier for making the nitrates or various metal carbonates for use as oxidisers. I
was under the impression that the nitric would require around the same amount of precaution as hydrochloric needs.
However, today when Dad went to pick it up whilst I was at school, he received a large lecture from the manager of the chemical store on how this is
"bad shit" and that even small amounts will erode the lining of my lungs.
We just had an argument on the actual danger vs the MSDS. The MSDS won out.
So I ask you science madness, could you please provide some proof to show that nitric isn't actually THAT dangerous when you know what you are doing
around dangerous chemicals so that I can print it out and show him?
Dad still thinks it is dangerous because it produces Hydrogen when reacted with a metal (which it normally doesn't do anyway at this concentration).
This is really starting to bug me - it's not like I was going to do anything unsafe. I just wanted my oxidisers and perhaps some lead nitrate to
electroplate my platinum anode to finally find a working PbO2 design and contribute on here.
My quest for reagents was going quite well until this. I mean, it's not like it's Perchloric acid and something like that - it's a freakin' regularly
used reagent.
Thank you.
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ScienceGeek
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Wikipedia has a good and accurate section on this, but to sum it up:
Everything is dangerous if not handled properly, implying everything is safe IF handled properly. Precautions should be taken so that you don't get
any on your skin! Not "dangerous", per se, but it hurts like hell after a little while! I tested my latex- gloves with 66% Nitric Acid, so they can be
used safely! (I would remove them if they got spilled on, though)
68% Nitric acid is an oxidising acid, yealding Nitric Oxide (NO2) gas when reacted with a metal. This is extremely dangerous to your lungs, especially
because it doesn't smell as bad as Chlroine! Pulmonary edema could follow switfly after a larger dose of inhaled Nitric Oxide.
When you order a drum of nitric acid, you usually know what you're doing, and with this in mind, Nitric acid will be your best friend soon
enough!
[Edited on 11-3-2008 by ScienceGeek]
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497
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I don't think nitric is all that dangerous. Maybe I underestimate it, but I've used it a bit and never been damaged. I think most important is *don't
get it in your eyes*. Goggles might not look so attractive but wear them anyway. As long as you wash it off quick it won't do too much damage to your
skin. Concentrated sulfuric is definitely worse in that respect. Don't drink it, don't take a bath in it, don't be dumb (like spill 20L of it) in
general and you'll be fine.
In respect to NO2, it will probably not be generated in large amounts unless the acid is hot and/or the metal is very high surface area (powder). A
little puff of NO2 isn't a big deal, if you believed everything the MSDS and Wikipedia said you would think it was as bad as phosgene. Definitely try
to avoid breathing it but producing a little bit is no reason to freak out and call HAZMAT. One whiff and you're not going to drop dead. If you end up
producing very much (like a runaway nitration) just get out of the area and let it air out. It is conveniently red/brown and so not hard to miss.
There may be other hazards I failed to mention, I'll leave them to more experienced forum members.
You are very very lucky, I would love to have 20L of nitric! Where exactly did you get it? Have fun with it in any case.
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raiden
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| Quote: | Originally posted by 497
You are very very lucky, I would love to have 20L of nitric! Where exactly did you get it? Have fun with it in any case. |
I got it from a cleaning supplier. It was AU$145 for 20L.
Also, forgot to mention, dad isn't actually letting me touch it.
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Ephoton
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NO2 is evil stuff. do not take that a little puff idea as good advice if you ask me. I have desolved
lots of gold and platinium with the stuff mixed with HCl and a little bit of NO2 is not what you get.
dad not letting you touch it may not be the worst thing in the world.
it lubricates the lungs does NO2 then in a day or so turns to nitric acid and burns them.
the problem with NO2 is that it is very very slowly disolved in water or caustic solutions
so it is near impossible with out some transition metal magic to scrub it out of the air.
this means either pipping it in your lab ie lumps in your lungs in no time then ultimate death
or pipping it into the air helping the acid rain problem. you might think making a nitrate is just straight out disolve metal in nitric acid but what
happens is this. lets talk copper for example
Cu + 2HNO3 --> Cu(OH)2 + 2NO2 this is the oxidation step nice brown smoke some times it might
give you the clear NO instead meaning you dont even see the stuff but its just as bad.
then Cu(OH)2 + 2HNO3 ----> Cu(NO3)2 + 2H2O this is the nitration step not so bad but still requires
for a lot of metals the oxidation step.
this is way over simplified as well the oxides actualy form first and the
nitric acid steps the metals up there oxidation states each oxidation
releasing nitrogen oxides.
dangerous dangerous dangerous.
if you were to mix it with hydroxides I would say no probs its pritty safe except for the burn
factor and slow leach of oxides of nitrogen but to disolve metals is not a safe thing at all
and many countries have rules and regulations against it hence why some metals can only
be refined in some countries with lower EPA and health regulations.
[Edited on 11-3-2008 by Ephoton]
e3500 console login: root
bash-2.05#
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woelen
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HNO3 is much more dangerous than HCl. Metals do not give H2 with HNO3, but thick red/brown clouds of NO2. This gas is really dangerous. It kills you,
but with delay. Excessive exposure to this gas does not lead to immediate nasty effects, but 24 hours later you may have severe edemia.
Another difference with concentrated HCl is that the acid is a strong oxidizer and it may cause fire and/or explosion. A reaction, which at test tube
scale may look fairly innocuous, can become disastrous when scaled up by e.g. a factor 100. Remember, heat transfer speed goes up quadratically with
increase of amounts, but heat production goes up with third power. E.g. when you use 1000 times as much of liquid, then 1000 times as much as heat is
produced, but the surface area, at which the heat can be dispersed into the environment is only 100 times as large (provided that you do not use very
thin layers of liquid). Scaling up reactions with HNO3 is a severe risk.
HNO3 also can become dangerous, when it accidently comes in contact with wood, saw-dust, paper, etc. Again, small amounts are not severe, but larger
spills may lead to fire.
Finally, HNO3 is much more harsh to the skin than conc. HCl. Besides being a strong acid, it is a strong oxidizer as well. At 68% concentration, you
get yellow spots on the skin, which become hard and brittle after some time. A spot of a few square cm already can be quite irritating.
So, yes, HNO3 is more dangerous than HCl, but when used with caution and care, it is a nice chemical. I however, find a 20L drum somewhat excessive.
One or two liters of the acid is more reasonable to my opinion.
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YT2095
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I think I`d be most concerned as to it`s Mechanical safety, 20L (4 gallons) is A LOT of Nitric! and likely to be unwieldy, probably best to find a
Very safe home for it where it`ll not be moved ever and away from any potential causes of mechanical damage.
you`ll probably need an all plastic Turkey Baster or the likes to get the acid out to put into a smaller bottle for Lab use.
This is good as it also means your Stock doesn`t get Contaminated should a problem occur.
I must say though, I thought getting through 1L of 38% nitric a year was quite a lot (my average usage), so 20L @ 68% would see me into my 80`s !
actually, I have a 500ml bottle of 70% nitric here and I`v had it for about 3 years and only used about 150ml of it.
[Edited on 11-3-2008 by YT2095]
\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
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