jackson2004
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Need Help - Ammonia Question
If i where to liberate ammonia from ammonia solution or ammonia fertiliser ( ammonia salt ) in a test tube then have the gas transfered to a second
test tube containing a drying agent, then have that anhydrous ammonia transfered again.
What would i then have to do to have that ammonia gas in a liquid form in another test tube? Ammonia turnes to liquid at atmospheric pressure at -33c
and requires 100psi to turn to liquid i believe at room temperature. I believe gas cools as the pressure dropps but i do not know. I have seen similar
large scale ammonia generation online but do not really understand nor do i whant to produce more than 10ml liquid ammonia. Any help on this nano
scale consentrated ammonia gas generator would be appretiated. Thanks.
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guy
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I would say run it through a flask submerged under dry ice and acetone. This will be cold enough to liquefy the ammonia
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not_important
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Yeah, dry ice and acetone or alcohol will do. Small quantities will boil off pretty fast, you need to alway precool containers and so on.
Thee aren't a lot of agents you can dry ammonia with, and you'll want to dry it in the gas phase unless the generated gas is fairly dry to start with,
in which case condensing it and the distilling (by removing flask from the dry ice bath) into another cooled container will leave the water behind (if
there's only traces)
Dry ammonia itself is a pretty potent drying agent, and can cause 'burns' Plus it doesn't take much boiloff to give an amazingly strong amount in the
air; remember the ratio between liquid and gas phases.
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Magpie
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A little searching goes a long way:
http://www.sciencemadness.org/talk/viewthread.php?tid=4566&a...
The single most important condition for a successful synthesis is good mixing - Nicodem
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jackson2004
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I am not looking for a tutorial on how too build a compressor. I whant to know how you do this under atmospheric pressure. I was told there was a
simple home method that simply required some cooling ( not the compleate -33degrees though ) then the escape of ammonia at one point causes cooling to
below the -33degrees thereby producing ammonia
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not_important
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If the ammonia is at atmospheric pressure, then it's 'escape' isn't going to chill it. If it is under pressure, and cool enough, expansion can cool
some of it enough to liquefy; this was a common method of liquefying gases a one time, and still is used for making CO2 'snow'.
You can get cooling by evaporating ammonia from a water solution, using an air blast. I doubt you can enough cooling to get down to -33, though.
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ac-
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| Quote: | Originally posted by guy
I would say run it through a flask submerged under dry ice and acetone. This will be cold enough to liquefy the ammonia |
...Or just build a cascade cooling system which are capable of going down as -200C
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