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Polverone
Now celebrating 21 years of madness
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You can keep track of quantities by volume or by mass. I was suggesting that you could do it by mass if you had a reasonably precise and accurate
scale but lacked the glassware to do it volumetrically.
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Is there any acid strong enough to form NO2 from KNO2 that can be purchased from a pharmacy? I want to get to just seeing what happens qualitatively,
and convincing my parents to allow acid in the house.
If you would be kind enough to redirect me to a thread where this is discussed, I'd do some research on here and elsewhere.
Right now I'm thinking of just doing a 6 g mix of 3:2:1 of KNO3:Al:Sugar or Charcoal (or both).
Stupid question here: By "molten salts in the acidic permanganate", do you mean actually molten (in the liquid state), or dissolved(aqueous)?
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Nitrous acid is very weak, so most acids that aren't easily oxidized should work. Citric acid should be fine. I wouldn't use vinegar, for two reasons:
it is strong enough, but it is not concentrated enough. Unless you have a large proportion of nitrite present it is likely to give a solution of
nitrous acid instead of visible fumes. Second, the strong smell of acetic acid is likely to interfere with the more sensitive instrument of your nose.
Invisible levels of NO2 can be smelt if there are not other strong odors. As a rule, though, you should avoid breathing NO2: it is quite toxic. You
would want to treat it like chlorine if you're trying to detect it by odor.
This is the nitrite production thread. There's a fair amount of nonsense in there, perhaps some of it written by me, as is usually the case with
long threads. At least it shows that there are quite a few members interested in producing nitrites from nitrates.
You would be titrating an aqueous solution of salts produced from high-temperature nitrate reduction, not the still-molten salt mixture.
Take a look at Journal of the Society of Dyers and Colourists, Volume 7 starting on page 183. You want to read the article "The Estimation of Nitrous Acid in
Sodium Nitrite." The author's suggested method of titrating a known quantity of warm, acid KMnO4 solution with a nitrite mixture is the one I would
suggest you follow. It should be tolerably accurate and simple and the chemicals are easy to get.
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I'd be happy to know just the rough percentage of nitrites in the result. Should I test a control with some regular potassium nitrite obtained from an
external source? I've heard that it's a meat preservative. |
If you can get pure potassium or sodium nitrite for practice and calibration of your methods that would be great. You can order it at a decent price
from, for example, Pro-Cure Bait Scents. I don't know how much shipping will be, though. I have never seen pure nitrites at a retail outlet, only curing mixtures
that contain some small percentage of nitrite. You could try testing those too, as long as you can get a kind that contains only inorganic salts.
Those with sugar or flavors mixed in will interfere with the permanganate reaction.
PGP Key and corresponding e-mail address
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Rich_Insane
Hazard to Others
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Nitrous acid is very weak, so most acids that aren't easily oxidized should work. Citric acid should be fine. I wouldn't use vinegar, for two
reasons: it is strong enough, but it is not concentrated enough. Unless you have a large proportion of nitrite present it is likely to give a solution
of nitrous acid instead of visible fumes. Second, the strong smell of acetic acid is likely to interfere with the more sensitive instrument of your
nose. Invisible levels of NO2 can be smelt if there are not other strong odors. As a rule, though, you should avoid breathing NO2: it is quite toxic.
You would want to treat it like chlorine if you're trying to detect it by odor. |
I've tried vinegar before to neutralize the mess left over. Nothing big happened. One time I scraped some of it off, placed it in a 250 ml beaker,
added vinegar, dumped the vinegar, and added Acetone. The solution turned very milky, despite me getting rid of almost all the vinegar. Any indicator
of anything?
[img] This is the nitrite production thread. There's a fair amount of nonsense in there, perhaps some of it written by me, as is usually the case with
long threads. At least it shows that there are quite a few members interested in producing nitrites from nitrates. You would be titrating an aqueous
solution of salts produced from high-temperature nitrate reduction, not the still-molten salt mixture. Take a look at Journal of the Society of Dyers
and Colourists, Volume 7 starting on page 183. You want to read the article "The Estimation of Nitrous Acid in Sodium Nitrite." The author's suggested
method of titrating a known quantity of warm, acid KMnO4 solution with a nitrite mixture is the one I would suggest you follow. It should be tolerably
accurate and simple and the chemicals are easy to get.[/img]
Thanks. Do you have any recommendation of how I should store KMnO3, other than keeping it away from acids?
[Edited on 9-2-2010 by Rich_Insane]
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Polverone
Now celebrating 21 years of madness
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I don't think your milky mixture indicates anything in particular. The KMnO4 you get should be kept in whatever container it was sold in. The acidic
solution that you use for titration should be kept in something that is resistant to oxidizers and acids alike. A glass bottle with a glass stopper
would work. Some plastics might also work but I can't advise what.
Permanganate leaves brown MnO2 stains on anything oxidizable, like fabric, skin, and paper. You will want to have some ascorbic acid or metabisulfite
solution to clean up the stains.
PGP Key and corresponding e-mail address
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ScienceSquirrel
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Mood: Dogs are pets but cats are little furry humans with four feet and self determination! 
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Quote: Originally posted by Polverone  | I don't think your milky mixture indicates anything in particular. The KMnO4 you get should be kept in whatever container it was sold in. The acidic
solution that you use for titration should be kept in something that is resistant to oxidizers and acids alike. A glass bottle with a glass stopper
would work. Some plastics might also work but I can't advise what.
Permanganate leaves brown MnO2 stains on anything oxidizable, like fabric, skin, and paper. You will want to have some ascorbic acid or metabisulfite
solution to clean up the stains. |
In my opinion the best containers for almost all solid chemicals are HDPE jars with lids made of the same material. They are not as heavy as glass,
light proof and do not shatter when dropped.
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Rich_Insane
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Location: Portland, Oregon
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Ok, so I won't need anything Teflon coated at this point? I'm sure that that stuff can get expensive, so i want to be sure that I need some before I
try to get any.
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