Picric-A
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UN and NU
This is going to sound extremly nooby but anyway 
Ii am realy confused about the two compunds Urea nitrate and NitroUrea. Through searching i havnt found much information to show the differences...
I understand Urea nitrate is made by making a saturated soloution of urea and adding nitric acid. Will the urea neutralise the nitric? how do i know
when i have added enough nitric?
Now from the thread about sulpamic acid i guessed Nitrourea is made by adding sulphuric acid to the urea nitrate. could someone elaborate on this? for
example conc sulphuric or dilute sulphuric acid? reflux? temperature?
Apart from explosives wich i would rather stay away from...what else are these compunds used for?
thanks fot the help
Picric-A
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12AX7
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Urea nitrate, or any other urea salt, can be produced by neutralizing a strong acid (such as HNO3, HCl, H2SO4, HClO4, etc.) with urea. Any pH
indicator suitable for the range can be used; the endpoint will be very acidic, because urea is a very poor base.
Urea nitrate I suppose might be termed urium nitrate, or since that doesn't really work, using the alternate name, carbamidium nitrate. This has the
structure H2N-CO-NH3(+) NO3(-), an ionic salt. Since urea has two amines, it could be protonated twice, but it's so electropositive I don't think you
will ever get much. H2O can be removed (usually with the help of H2SO4, for two reasons), yielding H2N-CO-NH-NO2, nitrourea, which is not ionic.
The two reasons H2SO4 is useful for nitrourea are, for one, concentrated H2SO4 is a strong dehydrating agent, so it absorbs H2O from the reaction,
forcing the equilibrium forward. Two, in the strongly acidic environment, NO2(+) (nitronium) ion is produced, which is strongly electrophilic and can
substitute the urea.
As for uses, I suppose you could reduce nitrourea to N-aminourea, H2N-CO-NH-NH2, which is better known as semicarbazide.
Tim
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S.C. Wack
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Preparation of Nitrourea.
200 g. of carefully dried urea nitrate was added in small portions at a time with stirring to 300 ml. of concd. sulfuric acid (1.84) while the
temperature of the mixture was kept below 0°. After the last portion had been added, the cold milky mixture was allowed to stand for one minute and
was then poured into a liter of ice and water. The finely-divided white precipitate was collected on the filter, sucked as dry as might be, and,
without washing, was immediately dissolved while still wet in boiling alcohol. (The precipitate still contained enough acid to prevent the
dearrangement of the nitrourea in boiling alcohol. For a second recrystallization it was found to be unsafe to heat the alcohol above 60°.) The
liquid deposited pearly leaflets on cooling. It was chilled in ice water before filtering and the crystals were rinsed with cold alcohol. The
alcoholic mother liquors were used for the crystallization of several successive batches. The air-dried product was sufficiently pure without another
crystallization. Samples of it have remained unchanged in hard glass bottles for several years; yield, 90% or better.
JACS 51, 1790 (1929)
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franklyn
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My reply is not intended to be rude. From your rambling query even to me who
is not a chemist, it's evident you know jack shit about chemistry. Consider that
before you embark on making imprudent quantities of explosive compounds.
Urea nitrate is an ionic organic salt not much different from an inorganic salt.
( there are however technical nuances I won't trouble you with here ) It is the
condensation of 1 mol of urea with 1 mol of nitric acid. (NH2)CO•HNO3
roughly 49% urea to 51% nitrate by weight
Using a weight scale and graduated cylinder you assay the acid by comparing
what you measure to the known properties of the pure acid.
Nitric acid
63.012 gm/mol , 1.51 gm/cc , 41.30 cc/mol
Urea
60.070 gm/mol , 1.33 gm/cc , 45.17 cc/mol
The urea can be added directly to watered down ice cold nitric acid in meager
amounts at a time until all is dissolved, not allowing the temperature to rise.
Urea nitrate crystals are insoluble in cold water, but soluble in hot, thus filtering
hot and chilling the liquor will precipitate most of the crystals out relatively pure.
It is very acidic and will corrode metal containers
Nitrourea is an organic molecular compound it may be prepared from urea nitrate
in concentrated sulfuric acid at 0°C to +5°C afterward dousing with ice.
Nitrourea may be obtained in a pure condition by recrystallization from ether,
benzene, or chloroform, in which solvents it does not dearrange. Although not as
acidic it is reactive enough that it will hydrolyse and degrade due to tautomerism.
(O2N).HN.CO.NH2 <=> (ON).HON.CO.NH2
You may find the following useful
Chemistry for the Utterly Confused.pdf
http://www.badongo.com/file/10925988
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Picric-A
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12AX7 and S.C. Wack - thanks for the help, i will porbably try these synthesis today using gram quantities to start.
S.C. Wack - 'My reply is not intended to be rude' yea... as if!
i dont care what you think about me knowing little chemistry, i have just started getting into organic chemistry, i havnt been taught it at school,
(as i am 14) so the little i know is self taught. Everyone has to start somewhere and asking questions is part of the learning process. The fact that
i asked a simple question and two members, 12AX6 and S.C. Wack , were able to asnwer it in a helpfull way says something about you...
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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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I would ask if you think that urea nitrate and nitrourea is the best place to start for someone who knows little about organic chemistry.
While they are not wildly nasty they should be handled with some care.
If you have not already done so maybe you could try some experiments with more easily handled materials first.
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Picric-A
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I spent around a year synthesising and detonating primary and secondary explosives, i am not an idiot when working with them. I meerly wanted some
information on the chemistry side of them, soz if im sounding snappy lol 
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Picric-A
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ok i have finally got round to synthesying some urea ntirate.
i made a almost saturated soloution of urea then slowly added abut 49% nitric acid to it.
immedietly a white precipitate formed wich i presumed to be urea nitrate. I am currently drying it.
any ideas on how i can prove it to be urea nitrate?
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Sauron
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Franklym was absolutely right. Spend less time posting worthless threads and more time reading chemistry. If explosives are what you are interested in
study David. Study PATR. Study Urbanski. But study SOMETHING. The difference between urea nitrate and nitrourea is obvious to any chemist from the
names alone and certainly from the structural formulas.
You communicate like a hydrocephalic, and don't give us any more blather about typos. If you are too lazy to learn how to spell, use a spell checker,
so as not to insult those of us who have some appreciation of the language.
Sic gorgeamus a los subjectatus nunc.
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