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Ghislain
07-21-2013, 11:17 PM
I carried out an experiment to try and condense Nitrogen Dioxide and hopefully create fuming Nitric Acid.

Perhaps this should be listed under Practical Chemistry?

I have placed the images in links as they are a bit large to put in the post.

The Set Up (http://forum.alchemyforums.com/attachment.php?attachmentid=763)

The experiment was unsuccessful as there was not enough Nitrogen Dioxide produced to carry over into the
condenser, but you can watch the experiment at the link below. Don’t expect too much as this has to be the
worst video I have ever made lol. Ignore the sound, I have inserted text where needed.

My Failed Experiment :( (http://youtu.be/umkFHGhisGo)

I did have the reaction flask on a magnetic stirrer and Nitrogen Dioxide is paramagnetic so this may have had
an effect on the result.

However I did manage to produce this:

Reaction Flask Fluid (http://forum.alchemyforums.com/attachment.php?attachmentid=764)

This is the liquid produced in the reaction flask. I couldn’t say what it is, but it is fuming and when I placed it
on some Gold it didn’t react with it, as I would expect with Nitric Acid.

I left it for a while to be sure nothing was happening and then added some common salt to the mix to provide
chloride and this started the reaction I was looking for...the Gold dissolved.

Dissolved Gold (http://forum.alchemyforums.com/attachment.php?attachmentid=765)

Ghislain

Ghislain
07-23-2013, 05:41 PM
One of the goals of this experiment was to make some Gun Cotton
This is done by nitrating the cotton and you need to soak it in the fuming
nitric acid.

The thing was that every time I put cotton wool into the resulting liquid of
the above experiment it just dossolved it.

The liquid, in its glass, was forgotten and left outside over night. When I next
saw it the liquid was quite black...it took me a while to remember what it was. This
was left out and it stood in direct sunlight. Later that afternoon I caught sight of it
and was surprised to find it has gone clear and was fizzing. Again I left it in the
same position and now it looks dark red. (see pic below)

http://forum.alchemyforums.com/attachment.php?attachmentid=769

Light green -> black -> clear -> red...

Any ideas?

Ghislain

JDP
07-24-2013, 02:12 AM
One of the goals of this experiment was to make some Gun Cotton
This is done by nitrating the cotton and you need to soak it in the fuming
nitric acid.

The thing was that every time I put cotton wool into the resulting liquid of
the above experiment it just dossolved it.

The liquid, in its glass, was forgotten and left outside over night. When I next
saw it the liquid was quite black...it took me a while to remember what it was. This
was left out and it stood in direct sunlight. Later that afternoon I caught sight of it
and was surprised to find it has gone clear and was fizzing. Again I left it in the
same position and now it looks dark red. (see pic below)

http://forum.alchemyforums.com/attachment.php?attachmentid=769

Light green -> black -> clear -> red...

Any ideas?

Ghislain

For making guncotton you will need:

1- Strong nitric acid

2- Concentrated sulfuric acid

To concentrate the sulfuric acid is easy. Just put it in a beaker on a hot plate and heat it until it starts emitting white fumes. That leaves a pretty concentrated acid. Bottle it and cap it, as it will start absorbing moisture from the air if you leave it in an open container.

To prepare the strong nitric acid is trickier and needs distillation equipment (with ground glass joints.) The simplest method is to buy 50% to 70% commercial nitric acid (many chemical suppliers sell these grades of nitric acid to anyone, no permits or questions asked) and then mix it with its own volume of concentrated sulfuric acid, and then carefully distill the mixture. Most of the water in the nitric acid will remain behind with the sulfuric acid, while the nitric acid distills into the receiver with a much stronger concentration. If you take this first distilled nitric acid and repeat the procedure again with another volume of concentrated sulfuric acid, you end up with an even stronger nitric acid. This will nitrate cotton quite well in conjunction with concentrated sulfuric acid.

By the way, nitrating cotton is not "alchemy", just ordinary chemistry.

Ghislain
07-24-2013, 05:57 AM
JDP

The Gun Cotton was just for fun

My boy and I like to make things that go Bang (http://genius.toucansurf.com/BANG.wmv). :)

Ghislain

theFool
07-24-2013, 01:23 PM
Ghislain,
it is feasible to make nitric acid with this method. Watching relevant videos on youtube, I managed to make a device that could produce around 50ml of azeotropic acid during one week of operation. Used a neon sign transformer and an aquarium pump. Never needed more acid than this for some years now, I have "lost" the device, but if someone is interested for more details I could offer.

Ghislain
07-25-2013, 11:01 AM
Thanks TF

I shall try distilling what I have...perhaps there is nitric trapped in there.

Ghislain

Ghislain
07-26-2013, 07:36 PM
oops sorry JDP...thanks to you too.

Ghislain

Ghislain
10-26-2013, 10:46 PM
I kept the acid I made in a jam jar which had a lid lined with a plastic that I thought would contain it.

I was wrong, below is a video of the second jar I have used. Note the acid has never directly touched
the lid it is just the fumes from it that did the damage.


http://www.youtube.com/watch?v=4Ed3g0QzuZU&feature=youtu.be

Ghislain

JDP
10-27-2013, 06:45 AM
I kept the acid I made in a jam jar which had a lid lined with a plastic that I thought would contain it.

I was wrong, below is a video of the second jar I have used. Note the acid has never directly touched
the lid it is just the fumes from it that did the damage.


http://www.youtube.com/watch?v=4Ed3g0QzuZU&feature=youtu.be

Ghislain

Nitric acid vapors/fumes corrode almost everything, that's why you can't use simple glass bottles with rubber stoppers and glass tubes to prepare it (the rubber stoppers are quickly corroded.) The 60 to 70% nitric acid sold by chemical suppliers in glass bottles have a cap and sealing ring of a plastic that resists the action of these vapors but only for those concentrations of nitric acid. When you store "red fuming" nitric acid in those bottles the rings and caps start to show signs of damage after a few weeks of storage, so they do not work for long term storage of the more concentrated nitric acid. The only things that can be used to close bottles containing red fuming nitric acid are ground glass stoppers and/or teflon.

black
10-27-2013, 07:50 AM
822Hi Ghislain

I have worked with these caps for many years. They have a limited life but are the best that I have found. Like all lab-equip they are bit pricey.
Made by Pyrex and Schott.