Oscilllator
National Hazard
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Calcium hypochlorite and sulfur reaction
A small amount of sulfur (from a gardening store) and Calcium hypochlorite (as pool chlorine) was mixed together then put in a test tube. The test
tube was heated with an alchohol burner and almost immediately an orange colour was observed. The mixture in the test tube then proceeded to boil and
release a moderate amount of stinky white gas that was so dense it was pourable.
This continued until all of the mixture was splotchy orange and white. The orange substance appeared to be some sort of liquid, but it solidified as
the test tube cooled.
After it was cool, There was a small amount of sulfur deposited on the walls of the test tube, and when water was poured into the test tube, an
exothermic reaction proceeded with the evolution of more of the white gas.
Anyway, does anyone know what this reaction produces? I think there might be some sulfur chlorides going on here, but thats just a suspicion. It could
also be that the white gas observed during the reaction was water hanging around in the reagents.
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elementcollector1
International Hazard
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The orange is likely to be liquid sulfur, possibly diluted or distorted in color by the calcium hypochlorite (pure stuff melts bloodred). The white
gas was very likely H2S, SO3 or SO2 (the first one is the most likely) produced from CaS and H2O (although I wouldn't know where the chlorine went in
this reaction).
Elements Collected:52/87
Latest Acquired: Cl
Next in Line: Nd
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Mixell
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I doubt it was H2S, it's an oxidizing and not a reducing environment (and the OP is alive and presumably in good health) . SO3 most definitely
wouldn't have formed, it's a liquid at room temperature and it's would have immediately reacted with any water present.
In addition to that, H2S is only ~15% denser that air, while SO2 is twice as dense.
I would say it was sulfur dioxide.
The orange substance might be some sort of a poly-sulfide with chlorine atoms attached to it, I don't really see another explanation for an orange
solid. And the addition of water probably disturbed some weak protective layer over the solid and allowed it to further hydrolyze, releasing SO2.
That's the best explanation I can offer which accounts for a hydrolyzable orange solid containing sulfur...
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Oscilllator
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Alright, I ran the experiment again, and obtained a few more observations:
Once rinsed with copious quantities of water, the product was this yellow stuff that had a consistency somewhere between that of jelly and rubber.
Obviously some sort of sulfur polymer there.
I poured a little bit of water into the dry test tube after the reaction had finished, then poured it out. Unsurprisingly, the water was strongly
acidic, as measured by universal indicator.
The white gas that came out was very opaque, more opaque than the sulfur dioxide I have seen in the past. It also didn't really smell like sulfur
dioxide, it had some distinct "chloriney" component to it. Having said that, it could have been sulfur dioxide with some other chlorine component.
Well, I hope those observations narrow down the options.
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Mixell
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The "chloriney" smell and the acidic solution are both due to hydrolysis of the S-Cl bond, which releases HCl and SO2. The opaqueness is probably due
to some volatile sulfur chloride reacting with water vapor and creating tiny droplets of acid (much like sulfur trioxide fumes in air).
That's not the issue here, I am more curious as to what exactly is that yellow-orange solid.
I think it's most certainly some mix of different sulfur polymers with different atoms and functional groups attached to them (like -Cl and -OH).
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AJKOER
Radically Dubious
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OK, most likely is S2Cl2 or SCl2, formed a follows:
S8 + 4 Cl2 → 4 S2Cl2
S2Cl2 + Cl2 → 2 SCl2
Pure disulfur dichloride, S2Cl2, is a yellow golden liquid that smokes in air due to reaction with water:
2 S2Cl2 + 2 H2O → SO2 + 4 HCl + 3/8 S8
Per wikipedia (http://en.wikipedia.org/wiki/S2Cl2 ), to quote:
"Disulfur dichloride has the ability to dissolve large quantities of sulfur, which reflects in part the formation of polysulfanes:
S2Cl2 + n S → S2 + nCl2 "
Not so likely is SOCl2 as it reacts with water violently to release hydrogen chloride and sulfur dioxide.
SOCl2 + H2O → 2 HCl + SO2
which could be formed via:
SO2 + Cl2 + SCl2 → 2 SOCl2
Also, not so likely is SO2Cl2, which is prepared by the reaction of sulfur dioxide and chlorine usually in the presence of a catalyst ( activated
carbon):
SO2 + Cl2 → SO2Cl2
Also, Sulfuryl chloride reacts with water, releasing hydrogen chloride gas and sulfuric acid as follows:
2 H2O + SO2Cl2 → 2 HCl + H2SO4
SO2Cl2 is toxic, corrosive, and acts as a tearing agent (lachrymator). Like SOCl2, it can produce violent/explosive mixtures with water.
Note, the action of CO2 on moist Ca(ClO)2/CaCl2/Ca(OH)2 is observed to form Chlorine. As such, the slightly stronger acid gas SO2 (from the direct
interaction of S and Ca(ClO)2 or with air on heating) most likely as well also forms Cl2.
Caution: Do not heat Sulfur and Ca(OCl)2 in a confined space. In fact, I would not recommend performing this reaction at all with Calcium hypochlorite
as, to quote, "organic sulfur compounds, sulfides tend toward ignition and sometimes explosion" see http://www.chemicalbook.com/ChemicalProductProperty_EN_CB885... ).
[Edited on 11-3-2013 by AJKOER]
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