Jor
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unknow gas '(newbie question :[ )
Ok, well first dissolved some copper cion using a mixture of 3% hydrogen peroxide and acetic acid 5%. Acetic acid was in a slight excess. Then after
een hour of standing i poured about 5mL of the acquired very light blue solution (it was far from concentrated copper(II)-solution) in a test tube. I
then added 3 mL of 5% ammonia and the solution became blue (not very dark blue as the copper(II)-solution was quite dilute). Now, suddenly a lot of
bubbles began to form. My question is: What is the formed gas?
Myself, i was thinking ammonia was oxidised by the very small leftovers of hydrogen peroxide. There was also quite some acetic acid left so the gas is
definatly not ammonia as it would react with acetic acid. So whats the gas? nitrogen gas? or nitrous oxide maybe? It was no NOx as no brown colour was
observed.
[Edited on 7-12-2007 by Jor]
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YT2095
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why don`t you conduct the experiment fully? by doing the same as before but say lose the copper, and do another one with the Vinegar out the
equation, this is a good way to learn things and help you narrow down what it could be 
try and bring the whole thing down to the least possible variables but with the same result.
\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
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Jor
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It must be nitrogen with very small amounts of nitrous and nitric oxides i think, presuming ammonia does not catalyse hydrogen peroxide's
decomposition. I did not want to smell the gas, as i was kinda afraid that even very small amounts of hydrazine were formed.
And yes, i need to learn things as I'm just getting started with home chemistry. I only have ammonia, bleach, acetic acid, hydrogen peroxide,
potassium and sodium hydroxide, acetone, sodiumbicarbonate and ofcourse sodium chloride yet. I'm already ordering from several chemical suppliers and
I'm interested in inorganics. theory I know quite a lot already (a lot thanks to woelen ), but practise not yet  . because i have no metal salts yet, I'm
first focussing on copper (copper coins, at the moment acetic acid/hydrogen peroxide is only way to dissolve) before i got my lab set up and i got my
chemicals.
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12AX7
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Hydrazine isn't that easy to form, and I would suppose with the presence of a transition metal in solution (copper), won't form. I'm not keen on the
mechanism, but it's usually formed from hypochlorite, a somewhat different sort of oxidizer.
Most likely, your product was oxygen, due to the alkaline decomposition of peroxide.
Tim
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MagicJigPipe
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You are right, NH3 does not catalyze H2O2's decomposition. At least not aqueous ammonia.
"There must be no barriers to freedom of inquiry ... There is no place for dogma in science. The scientist is free, and must be free to ask any
question, to doubt any assertion, to seek for any evidence, to correct any errors. ... We know that the only way to avoid error is to detect it and
that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think,
free to think what they will, freedom can never be lost, and science can never regress." -J. Robert Oppenheimer
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