dracolique - 21-4-2006 at 18:29
Ok, first off, I dont know how nice people are on these forums, but please dont flame me for this... I am not a chemist, but I am trying to learn, and
I have what is probably an elementary question:
If I start with the mineral Mascagnite (NH 4 )2 SO4, then heat it to its decomposition point (~210c), and then pass the gas through a water (H2O)
scrubber, what will come out the other end?
I figure that having been heated and seperated from the sulfate, the Ionized Ammonium (NH 4) would seperate into its elements, and the sulfate would
do the same. Then, Oxygen from the Sulfate (SO4) would bond with the water in the scrubbers, the remaining Nitrogen from the Ammonium, and the
Hydrogen from the Ammonium, most likely creating more water (H2O), as well as Hydrogen Peroxide (H2O2) in the scrubbers... and expelling Dinitrogen
Monoxide (Nitrous Oxide) (N2O) from the end. The Sulfur should combine into its elemental state (S8), and be retained in the scrubbers.
Or, I could be completely off, and instead of getting N2O out the end, I would get Sulfur Dioxide (SO2). Or maybe I simply dont know anything about
anything, and none of the above would occur. Which is, of course why I am asking you guys.
[Edited on 22-4-2006 by dracolique]
[Edited on 22-4-2006 by dracolique]
[Edited on 22-4-2006 by dracolique]
neutrino - 21-4-2006 at 19:26
As long as you've put some effort into solving the question yourself we are usually pretty nice.
Ammonium (NH<sub>4</sub><sup>+</sup>
and sulfate
(SO<sub>4</sub><sup>2-</sup> are typical polyatomic ions.
They tend to stay together unless something breaks them apart, usually heat.
When heated, ammonium ions tend to break down like this:
NH<sub>4</sub><sup>+</sup> --> NH<sub>3</sub> + H<sup>+</sup>
I would expect one of the ammonium ions here to break apart. Compounds with multiple ammonium ions tend to loose only one at these (comparatively) low
temperatures. Your salt would decompose as follows:
(NH<sub>4</sub><sub>2</sub>SO<sub>4(s)</sub>
--heat--> NH<sub>3(g)</sub> + NH<sub>4</sub>HSO<sub>4(s)</sub>
You would be left with solid (?) ammonium hydrogen sulfate, aka ammonium bisulfate and ammonia gas escaping. Heated bisulfates form pyrosulfates and
decompose slightly into SO<sub>2</sub> and O<sub>2</sub>, but I doubt these would be significant at these temperatures.
Ammonia would totally dissolve in water and create ammonium ions and hydroxide ions. Nothing would escape the scrubbers.
dracolique - 21-4-2006 at 19:47
Ok, so if I increased the temperature, and perhaps introduced a vacuum, would I be more likely to see the kind of reaction described above? I am
running the experiment right beside me as I type this (I am in my garage).... I will know shortly if anything escapes the scrubbers.
dracolique - 21-4-2006 at 19:55
Also, what if I introduced Silicon Dioxide to original mixture being heated? Would the extra oxygen make a difference here?
dracolique - 21-4-2006 at 20:20
Something is escaping the scrubbers... its smells mildly like.... acetone.
dracolique - 21-4-2006 at 20:38
Ok, maybe I get scared easily, but I aborted the experiment... the Acetone smell was getting pretty strong, and the mixture in the flask was beginning
to become exothermic and self-perpetuating, even when I turned down the heat some.
Oh well. Maybe another time, in more controlled circumstances.
woelen - 22-4-2006 at 14:40
Smell of acetone? Are you sure that your ammonium sulfate is pure? Or, do you really know the smell of pure acetone? I do not know any chemical, which
could be made from ammonium sulfate, and which could smell like acetone.
kclo4 - 11-6-2006 at 00:47
if you increased the tempurature, the ammonium bisulfate, would decompose into sulfur trioxide, ammonia and water
NH4HSO4 <=> NH3 + H2O + SO3
However, the SO3 will react with the water, and make H2SO4. Then that will react with the ammonia and make NH4HSO4, really it would just sublimate,
but i dont know if it all leaves at the same time.
The bubbles from your expirment is probably ammonia gas that didnt get to disolve in the water, but i really dont know. ammonia really likes to
disolve in water, perhaps you have heard of the ammonia foutain?
Anyways i think the acetone smell might be some sort of waxy stuff, the only reason i think that is i suspect you are using ammonium sulfate
fertilizer?
or if its an actual mineral mined from the ground you have, it could have other things in it, such as nitrates, carbonates and those could be letting
off gases of some sort