liquid nitrogen
Nicholas M. Anderson
how much would it cost me?
how would I store it?
Nicholas M. Anderson
___
***Risk all, go extreme***
Kris Brown
it would cost, but I don't think it's too expensive (compared to a lot of
other chemicals). You store it in a special vacuum insulated container if
you want it to stay liquid for very long (that's the expensive part).
in article 93recg$920$1...@slb2.atl.mindspring.net, Nicholas M. Anderson at
neek...@hotmail.com wrote on 1/13/01 9:42 PM:
Josh Halpern
Kris Brown wrote:
> Get it at a local university or chemistry supply store. Not sure how much
> it would cost, but I don't think it's too expensive (compared to a lot of
> other chemicals). You store it in a special vacuum insulated container if
> you want it to stay liquid for very long (that's the expensive part)
Thermos bottles, or coffee containers (the kinds with silvered
glass inserts) will serve this purpose, and can be used to transport
the liquid nitrogen. DO NOT close the top tight, as the "boil off"
will in a short time burst the container. Either leave it completely
open, or even better, put a loose wad of tissue into the opening
as a porous plug. Once you get it where you need to use it
you can make a smaller container by stacking two or three
styrofoam cups inside each other.
josh halpern
Roy Jensen
take care of warts, etc.
At a university, expect to pay between 0.25 to 1$ per liter. Yes, it
is cheaper than gas. You had better have a good reason for, used
incorrectly, even a little can kill (most likely cause severe damage).
Roy Jensen
Eric Lucas
just as a precaution. You will likely need to convince the person you
are trying to get to give you the stuff that you know these things.
They will only be likely to give the stuff to someone that knows what
they're doing and how to do it safely.
1) You'll need to use it within hours of when you get it. Even the
proper liquid nitrogen dewars in my lab seldom keep even fairly large
quantities (4 L in my case) from evaporating overnight.
2) This stuff will cause severe skin burns if used improperly. There's
a Darwin award (or was it an Honorable Mention) from someone that drank
liquid nitrogen, thinking he remembered it could be done safely (!) He
suffered severe esophogeal and stomach burns, and if I recall, some part
of his digestive tract ruptured from the buildup of gaseous N2.
Remember, 1 mL of liquid nitrogen takes up about 1/2 L as a gas.
Eric Lucas
John Seeliger
<3A61E118...@worldnet.att.net>...
> 2) This stuff will cause severe skin burns if used improperly. There's
> a Darwin award (or was it an Honorable Mention) from someone that drank
> liquid nitrogen, thinking he remembered it could be done safely (!) He
> suffered severe esophogeal and stomach burns, and if I recall, some part
> of his digestive tract ruptured from the buildup of gaseous N2.
> Remember, 1 mL of liquid nitrogen takes up about 1/2 L as a gas.
There are many good responses to this message:
1. So, I guess you don't recommend trying this?
2. What a great way to cool down on a hot day!
3. Try drinking molten steel to warm up in the winter.
4. How dumb! Eating dry ice is much better.
Ian Gay
<3A61E118...@worldnet.att.net>:
[snip]
>1) You'll need to use it within hours of when you get it. Even the
>proper liquid nitrogen dewars in my lab seldom keep even fairly
>large quantities (4 L in my case) from evaporating overnight.
>
That's absurd. Time to get some new dewars, or have the old ones re-
pumped.
Eric Lucas
Ian Gay wrote:
Every 4 L Dewar I've ever used (including some new ones in grad school)
has allowed liquid N2 to boil off overnight. Vac line traps (more like
1L volume) don't even last an entire lab day, even without solvent
removal. Larger quantities will of course have smaller surface
area-to-volume ratios, and will keep the stuff for longer.
In any case, my point was the stuff is not a chemical you buy and keep on
the shelf--unless you're willing to pay for a 160 L dewar of it.
Eric Lucas
Eric Lucas
might be a welding supply house. Not sure if it's actually used in
welding, but welding supply houses have been the supplier of liquid
nitrogen and liquid argon in some of the places I've worked.
Eric Lucas
Dr. Henry
Without knowing your qualifications, I can not recommend using it
and I doubt that anyone will give it to you without knowing you.
Dry ice, which is dangerous itself, can be obtained more easily.
You need to be qualified to use it also.
--
Dr. Henry Boyter, Jr. Ph.D. Chemist
The opinions of Dr. Boyter are provided for informational
purposes only and should not be used as advice. No
warranty or expression of professionalism is implied.
***************
"Nicholas M. Anderson" <neek...@hotmail.com> wrote in message
news:93recg$920$1...@slb2.atl.mindspring.net...
Kris Brown
10-20L), and it would last forever.
in article 3A62089F...@worldnet.att.net, Eric Lucas at
eal...@worldnet.att.net wrote on 1/14/01 12:17 PM:
Josh Halpern
> Ian Gay wrote:
> > eal...@worldnet.att.net (Eric Lucas) wrote in
> > <3A61E118...@worldnet.att.net>:
> >> [snip]
> > >1) You'll need to use it within hours of when you get it. Even the
> > >proper liquid nitrogen dewars in my lab seldom keep even fairly
> > >large quantities (4 L in my case) from evaporating overnight.
> > >
> > That's absurd. Time to get some new dewars, or have the old ones re-
> > pumped.
>
> Every 4 L Dewar I've ever used (including some new ones in grad school)
> has allowed liquid N2 to boil off overnight. Vac line traps (more like
> 1L volume) don't even last an entire lab day, even without solvent
> removal. Larger quantities will of course have smaller surface
> area-to-volume ratios, and will keep the stuff for longer.
There are new ones designed for storage that last much
longer. Slightly larger Dewars tend to do much
better, ie we can keep samples in a 25 L dewar for a couple
of weeks In any case the key is to keep the top closed off
in such a way that no air can flow back into the dewar, but
boil off can escape.
josh halpern
Josh Halpern
Eric Lucas wrote:
> By the way, it just occurred to me...another place to get the stuff
> might be a welding supply house. Not sure if it's actually used in
> welding, but welding supply houses have been the supplier of liquid
> nitrogen and liquid argon in some of the places I've worked.
When you weld, you can use the boil off to exclude oxygen in
the air from the hot area of the weld. The wildest use that
I know of is that Con Ed in New York City puts 160 L dewars
on the street and uses the cold gas to cool transformer vaults
in the summer. The Dewars sit on the street all over Manhattan.
josh halpern
BAJJERFAN
should) sell you the stuff unless you can show a legitimate business need. They
do not sell hazardous material to walkins off the street.
donald haarmann
> When you weld, you can use the boil off to exclude oxygen in
> the air from the hot area of the weld. The wildest use that
> I know of is that Con Ed in New York City puts 160 L dewars
> on the street and uses the cold gas to cool transformer vaults
> in the summer. The Dewars sit on the street all over Manhattan.
>
> josh halpern
-------
The vast majority of the LN2 Dewars in Manhattan belong to the
local phone company. They are used to maintain air pressure
in cables keeping moisture out. Normally dry air is injected
at the local central office, however, in the event of a sheath
break when pressure cannot be maintained, nitrogen is put into
the cable near the break.
--
donald j haarmann - independently dubious
Eric Lucas
Josh Halpern wrote:
> The wildest use that
> I know of is that Con Ed in New York City puts 160 L dewars
> on the street and uses the cold gas to cool transformer vaults
> in the summer. The Dewars sit on the street all over Manhattan.
Hm, interesting. Never noticed LN dewars in my forays into NYC, but I
have seen compressed gas cylinders there, chained to lamp posts, fairly
often. Both He and N2, if memory serves. Never quite sure what they
were for. Tried to trace the lines attached to them, but only managd to
get to the nearest manhole. Could've been some sort of welding, I
suppose.
Eric Lucas
Bernhard Kuemel
> incorrectly, even a little can kill (most likely cause severe damage).
How could a little kill?? A little air can kill, too, if used
incorrectly. Well, you might get some bad burns if it was poured
on some clothing, but it would be hard to die from e.g. 1 l, I
guess, if you were so unfortunate to have it all poured on you.
--
Bernhard Kuemel Tel: +43/1/505-99-65
Adr: Brahmsplatz 7/11 dar...@gmx.at
1040 Wien BEKU1-RIPE
Austria/EUROPE
Bernhard Kuemel
I got some for free twice from Vienna technical university. The
last time I said I'd like to give my brother a cool :) birthday
present.
But we are lunatics over here in Austria. You know, we put real
candles on our christmas trees. Hoho, those paranoid Americans
:))).
Ivan Reid
wrote in <93t0o...@enews1.newsguy.com>:
>My two cents: Liquid nitrogen can be extremely dangerous.
>Without knowing your qualifications, I can not recommend using it
>and I doubt that anyone will give it to you without knowing you.
>Dry ice, which is dangerous itself, can be obtained more easily.
>You need to be qualified to use it also.
Up to this point, I have seen no mention of another hazard of LN2,
that it can lead to concentration of liquid oxygen, leading to fire or
explosion hazards. e.g. when you run LN2 through an uninsulated pipe, you
will first get water frost forming on the pipe, but subsequently this can
appear to "wet" with a liquid which condenses on the pipe and drips off --
this liquid is LO2, which has a higher boiling-point than LN2 (and IIRC,
a higher latent heat of vaporisation). I've also inadvertently created a
concentrated mix of LO2 in LN2 by having a fan blow across the top of an
open dewar of LN2 -- I didn't realise what was happening until I saw the
characteristic pale blue colour of LO2 in the dewar! (Normally the blanket
of evaporating gas minimises contact of normal air with the liquid; the
fan was disrupting this blanket and delivering O2-rich air to the cold
liquid.)
Another hazard I have seen mentioned, but never experienced, is
the possibility of a glass dewar imploding from stresses in the neck when
LN2 is poured from the dewar across the warm upper part of the neck.
--
Ivan Reid, Physics & Astronomy, University College London. i...@hep.ucl.ac.uk
KotPT -- "for stupidity above and beyond the call of duty".
donald haarmann
AB Kaufman and EN Kaufman
Cold Traps
EW Spencer
Cryogenic Safety
In:- CRC Handbook of Laboratory Safety
2nd ed. 1971 (I beleive there is a 3rd ed.)
And .....
Nickolas Kurti and Hervé This-Benchard
Chemistry and Physics in the Kitchen
Scientific American April 1994
"No good dinner is complete without dessert. From the world of physics comes a recipe
that not only eases the task of a chef but also produces a magnificent spectacle. This
dessert, instant ice cream, was devised by Peter Barham of the University of Bristol. As
a suitable finish for a public lecture on ice cream, Barham developed a way to make
enough of it in about two minutes to feed an entire audience. The same recipe can be
adapted to a domestic scale.
"Good ice cream contains abundant air bubbles (to keep it light) and only very small ice
crystals (so that the texture is smooth). Traditionally, ice cream makers have churned
the mixture of milk, eggs, sugar and flavorings as it slowly chilled: the churning folded
air into the material while also continuously breaking up large ice crystals. A simpler
and more efficient way is to pour liquid nitrogen directly into the ingredients. At a
temperature of -196 degrees C, liquid nitrogen can freeze the ice cream mixture so fast
that only small ice crystals have time to grow. As it furiously boils, the liquid nitrogen
also creates plenty of small gas bubbles. And as a further delight, the cold produces a
cloud of dense fog, thus adding a crowd pleasing, highly dramatic touch.
"You will need about equal volumes of liquid nitrogen and a mixture for ice cream or
sorbet. After preparing the mixture in the usual way, place it in a large metal bowl. (Do
not use a glass or plastic bowl, which might break from thermal shock.) While observing
the proper safety precautions (as set out below), pour in about half the liquid nitrogen,
stirring gently with a wooden spoon. Continue to stir while adding more of the coolant
until the ice cream is nice and stiff. Make sure the ice cream has stopped giving off
fog-which signals that all the nitrogen has evaporated-before serving.
"Two important safety points need to he made. First, always wear gloves and safety
glasses when handling the, liquid gas or any objects that have been exposed to its
extreme cold. Second, if you are making the ice cream in front of guests, be sure they
are out of range of any splashes. You should be able to obtain liquid nitrogen (or
directions to a commercial source for it) from your local university's physics or chemistry
department or from a hospital. The best way to transport liquid nitrogen is with a
vacuum flask; inside a well-made one, it will last for up to a day."
donald j haarmann
----------------------
The average woman would rather have
beauty than brains because the average
man can see better then he can think.
Anon.
Josh Halpern
just mix simple syrup and pureed fruit 1-1 and
then add LN2. It was quite good also, but
I'll have to try the ice cream.
josh halpern
donald haarmann wrote:
SNIP...
> Nickolas Kurti and Hervé This-Benchard
> Chemistry and Physics in the Kitchen
> Scientific American April 1994
>
> "No good dinner is complete without dessert. From the world of physics comes a recipe
> that not only eases the task of a chef but also produces a magnificent spectacle. This
> dessert, instant ice cream, was devised by Peter Barham of the University of Bristol. As
> a suitable finish for a public lecture on ice cream, Barham developed a way to make
> enough of it in about two minutes to feed an entire audience. The same recipe can be
> adapted to a domestic scale.
....
Roy Jensen
> > even a little can kill (most likely cause severe damage).
>
> How could a little kill?? A little air can kill, too, if used
> incorrectly. Well, you might get some bad burns if it was poured
> on some clothing, but it would be hard to die from e.g. 1 l, I
> guess, if you were so unfortunate to have it all poured on you.
Swallow it. 10 mL will generate 2.5 L of gas at a rate sufficient to
rupture your stomach and intestines. Of course, a stomach of steel
woul allow the contents to be ejected. Talk about projectile vomit and
the 'other end'.
Question: would there be enough force to rip denim pants?
Roy Jensen
Bruce Sinclair
:> Roy Jensen wrote:
:> > even a little can kill (most likely cause severe damage).
:>
:> How could a little kill?? A little air can kill, too, if used
:> incorrectly. Well, you might get some bad burns if it was poured
:> on some clothing, but it would be hard to die from e.g. 1 l, I
:> guess, if you were so unfortunate to have it all poured on you.
:
:Swallow it. 10 mL will generate 2.5 L of gas at a rate sufficient to
:rupture your stomach and intestines.
I suspect that the rate from liquid to gas would allow the gas to come
out rather than rupturing anything.
Even pouring some liquid N into hot water isn't very impressive :)
I wouldn't advise trying this experiment of course - it's knida silly :)
:)
Bruce
--------------------------------------------------------------------
Oook !
NOTE remove the not_ from the address to reply. NO SPAM !
tim_ro...@my-deja.com
vze2...@verizon.net wrote:
> [snap crackle pop]
> In any case the key is to keep the top closed off
> in such a way that no air can flow back into the dewar, but
> boil off can escape.
I think this is the key to the whole controversy. How long your
nitrogen stays liquid probably depends more on the venting method than
on anything else.
Sent via Deja.com
http://www.deja.com/
kres...@my-deja.com
Donald posts his usual tongue-in-cheek threadstopper, and somebody's
already done it. Only in sci.chem........
When in Texas I used to chill soft drink cans in a Dewar vessel with
about 20 ml of liquid nitrogen tipped over them - ready in about 90
seconds. I recall thinking the same thing about chilling food directly
- and then I noticed how much muck liquid nitrogen picks up - dust,
fluff, hair... It'd be good to pass it through a coffee filter
paper 'twixt Dewar vessel and dessert. But who am I to interfere with
an oft-repeated recipe?
In article <3A63555C...@mail.verizon.net>,
Josh Halpern
started out by putting the LN2 into an improvised dewar,
and the mixture to be frozen in a metal bowl that I placed
in the dewar, but that took two minutes and I said what
the hell and poured the LN2 directly into the mixture.
We are still alive (I think)
josh halpern
kres...@my-deja.com wrote:
> Donald posts his usual tongue-in-cheek threadstopper, and somebody's
> already done it. Only in sci.chem........
>
> When in Texas I used to chill soft drink cans in a Dewar vessel with
> about 20 ml of liquid nitrogen tipped over them - ready in about 90
> seconds. I recall thinking the same thing about chilling food directly
> - and then I noticed how much muck liquid nitrogen picks up - dust,
> fluff, hair... It'd be good to pass it through a coffee filter
> paper 'twixt Dewar vessel and dessert. But who am I to interfere with
> an oft-repeated recipe?
>
SNIP....
John Spevacek
>
> Donald posts his usual tongue-in-cheek threadstopper, and somebody's
> already done it. Only in sci.chem........
>
> When in Texas I used to chill soft drink cans in a Dewar vessel with
> about 20 ml of liquid nitrogen tipped over them - ready in about 90
> seconds. I recall thinking the same thing about chilling food directly
> - and then I noticed how much muck liquid nitrogen picks up - dust,
> fluff, hair... It'd be good to pass it through a coffee filter
> paper 'twixt Dewar vessel and dessert. But who am I to interfere with
> an oft-repeated recipe?
I've recently started working in the area of food microbiology. Give me
dust, fluff and hair any day. It's the stuff you can't see that should
scare you.
John
--
"Writing is God's way to show you how sloppy your thinking is."
Opinions expressed herein are my own and may not represent those of my employer.
James Harynuk
Bernhard Kuemel wrote:
> I got some for free twice from Vienna technical university. The
> last time I said I'd like to give my brother a cool :) birthday
> present.
>
> But we are lunatics over here in Austria. You know, we put real
> candles on our christmas trees. Hoho, those paranoid Americans
> :))).
>
Just after New Year's this year, chemistry decided to celebrate the
amount of snow we had so they built a great huge snow man, filled a 1L
plastic pop bottle with LN2, capped it, and stuck it inside the snow
man. I missed the actual event, but the video is pretty cool! :)
James
Roy Jensen
> amount of snow we had so they built a great huge snow man, filled a 1L
> plastic pop bottle with LN2, capped it, and stuck it inside the snow
> man. I missed the actual event, but the video is pretty cool! :)
Would you be willing to provide an avi or mpg of the event!!
Roy Jensen