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Zyklon-A
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Per Wikipedia:
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Aluminium chloride (AlCl3) is the main compound of aluminium and chlorine. It is white, but samples are often contaminated with iron trichloride,
giving it a yellow colour.
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So, it's yellow color is due to common impurities, has nothing to due with aluminum chloride, which is always white.
That's not to say that aluminum chlorosulfate isn't off-white, but I can't see how that's possible.
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blogfast25
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Re, AlCl3, the AlCl3.6H2O I once synthesized was also completely white.
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aga
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Elemental sulphur.
Thats the kind of colour it has, and it smells sulphurous.
Also chlorine-y.
However, CHRIS25 washed his in cold water, and the colour was washed out, so it's probably a Yellow Ion.
Does anybody have an ion/colour list readily to hand in order to set up the Candidates ?
Here's a list of Stuff that can be Yellow that i have found so far.
Elements/compounds of:-
Chlorine
Sulphur
Sodium
Barium
Uranium
Ions :-
Iodide
Tetrachloro-copper complex
Cobalt-ammonium complex
Iron(III)
Chromate
Pervanadyl
Sources:-
http://en.wikipedia.org/wiki/Color_of_chemicals
http://www.sanjuan.edu/webpages/dkrenecki/files/ColorsofSubs...
If i were using Aluminium Sulphate derived from the CuSO4 route, i'd suspect the Tetrachloro-copper complex, however this Aluminium sulphate was made
via the Sulphuric acid + Aluminium route.
The prime candidates for the Yellow colour are Chlorine and Sulphur.
Iron is less likely, in that it is hard to see where it came from.
If it were copper or Chromate ions, that could come from cheapo chrome plated copper spatulas, however they were not used in any part of the
processes.
If it were Uranium, i would definitely remember adding it.
[Edited on 4-6-2014 by aga]
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The Volatile Chemist
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Quote: Originally posted by aga  | Elemental sulphur.
Thats the kind of colour it has, and it smells sulphurous.
Also chlorine-y.
However, CHRIS25 washed his in cold water, and the colour was washed out, so it's probably a Yellow Ion.
Does anybody have an ion/colour list readily to hand in order to set up the Candidates ?
Here's a list of Stuff that can be Yellow that i have found so far.
Elements/compounds of:-
Chlorine
Sulphur
Sodium
Barium
Uranium
[...]
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Barium? yellow? Looking at your first source, it says a flame test gives green/yellow. If that's where you got the idea barium compounds could be
yellow...  A flame test has little to do with actual coloration of compounds. If
you do actually know of a yellow barium compound, tell me! I want to bring some color to one of my mostly white chemicals
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blogfast25
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Volatile Chemist:
Barium chromate.
Jokes aside though, allow me to test for the most LIKELY culprit first (no, aga, it's NOT uranium  ) before we we set off on a wild goose chase, i.e. ferric ions.
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The Volatile Chemist
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But isn't the chromium the cause of the coloration, not the barium???
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blogfast25
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VC:
Of course but you asked for a yellow barium compound? Your will is our command! 
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The Volatile Chemist
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I hardly use the word, but LOL. I bring it up because barium ions just don't cause yellow color, which is what we're talking about. But chromium
compounds? I love em
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aga
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Apparently some Barium ions/compounds/complexes Can give a Yellow/Green colour.
I included Everything i could find a reference to that *could* give a Yellow colour.
It is highly unlikely to be Barium, seeing as i have never used barium or a barium compound in these pieces of glass.
I'd put Barium contamination on a par with Uranium.
Sulphur or Chlorine.
My bet is on Sulphur.
Each way bet. Might be Chlorine.
[Edited on 4-6-2014 by aga]
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The Volatile Chemist
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| Quote: Originally posted by aga | Apparently some Barium ions/compounds/complexes Can give a Yellow/Green colour.
I included Everything i could find a reference to that *could* give a Yellow colour.
It is highly unlikely to be Barium, seeing as i have never used barium or a barium compound in these pieces of glass.
I'd put Barium contamination on a par with Uranium.
Sulphur or Chlorine.
My bet is on Sulphur. |
Sure, I'll bet it's chlorine dioxide... 
I wasn't saying it would be barium, though it's more likely than uranium (minimal still) because glass can be made of barium for spectroscopic
reasons, but still ridiculously (to the point of being absurd) unlikely.
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aga
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| Quote: | | glass can be made of barium for spectroscopic reasons |
Worth mentioning.
I didn't know that, and Glass has been used extensively.
Borosilicate glass actually.
Seems Silicon & Boron aren't Yellow though.
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blogfast25
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How much are you willing to wager? I'm not a betting man but I do like a dead cert (Fe<sup>3+</sup>.
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aga
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A Small Hadron Collider.
Spit. Deal Done !
I doubt that i have the reagents to test for Fe ions.
I'd best buy some to settle the matter.
[Edited on 4-6-2014 by aga]
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blogfast25
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Not fair.
You're already sending me one of those.
If you want to chicken out, just say so!
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aga
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Oh dear.
You said the C word.
You have no idea.
None, due to the unseen Dimensions at work behind that word.
P'kaaark !
[Edited on 4-6-2014 by aga]
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aga
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Ok.
How did Fe enter the chain ?
Candidates are :-
1. OTC Aluminium Foil
2. OTC Drain Opener (brown) Sulphuric acid
3. OTC 3% H2O2
4. 25 w% HCl from a reputable dealer
5. poor physical hygiene : dirty glassware, iron fingers etc.
6. poor mental hygiene (imagining it was all simple)
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blogfast25
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In order of likelihood (my opinion): 4, 1, 2. Unlikely: 3, 5, 6
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CHRIS25
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The following Not possible: 1,2,3,5,6, that leaves 4. I did not use foil I used aluminium metal, cleaned and washed, I am not aware that
aluminium metal pipe can contain Iron? Mine came from years in the sea, close to 50year old dead boats. No signs of pitting or discolouration. Maybe
trace amounts of iron in some manufacturing process? Possible? No idea.
[Edited on 5-6-2014 by CHRIS25]
‘Calcination… is such a Separation of Bodies by Fire, as makes ‘em easily reducible into Powder; and for that reason ‘tis call’d by some
Chymical Pulverization.’ (John Friend, Chymical Lectures London, 1712)
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. (William Penn 1644-1718)
The very nature of Random, Chance development precludes the existence of Order - strange that our organic and inorganic world is so well defined by
precision and law. (me)
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blogfast25
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Chris:
Trace amounts Fe are possible in Al commercial metal, possibly more in some alloys. But your ASH was snow white, indicating very low levels of Fe.
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CHRIS25
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| Quote: Originally posted by blogfast25 | Chris:
Trace amounts Fe are possible in Al commercial metal, possibly more in some alloys. But your ASH was snow white, indicating very low levels of Fe.
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Ok then. Just found a whole lot of people saying No not possible, but then came across one comment from someone who works in an aluminium sheet
factory who said that he has to test the final product for a trace analysis and there is always Iron to be found usually less than 5% by weight. Yes
my Al sulphate is snowy white, no visible yellowing at all.
‘Calcination… is such a Separation of Bodies by Fire, as makes ‘em easily reducible into Powder; and for that reason ‘tis call’d by some
Chymical Pulverization.’ (John Friend, Chymical Lectures London, 1712)
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. (William Penn 1644-1718)
The very nature of Random, Chance development precludes the existence of Order - strange that our organic and inorganic world is so well defined by
precision and law. (me)
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DraconicAcid
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| Quote: Originally posted by CHRIS25 | | Quote: Originally posted by blogfast25 | Chris:
Trace amounts Fe are possible in Al commercial metal, possibly more in some alloys. But your ASH was snow white, indicating very low levels of Fe.
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Ok then. Just found a whole lot of people saying No not possible, but then came across one comment from someone who works in an aluminium sheet
factory who said that he has to test the final product for a trace analysis and there is always Iron to be found usually less than 5% by weight. Yes
my Al sulphate is snowy white, no visible yellowing at all. |
The yellow colour of iron(III) is much more intense when it's got chloride ions as ligands. I'm not surprised that the sulphate isn't yellow, but
only turns yellow when you add HCl.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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blogfast25
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Left: supernatant liquid from that run, light yellow.
Right: same but with a bit of 1 M KSCN added.
The colour is due to the complex FeSCN<sup>2+</sup> cation, which is deep wine red in high concentration.
In the mean time I’ve also broken up my crystalline mass of product and washed it with small aliquots of iced water. Normally I would suck them dry
on my Buchner but it’s not available right now. So I patted them dry, put them on a piece of filter paper (and some kitchen towel underneath) and
will allow them to dry in the fridge. Then some more drying in a silicagel desiccator.
A small amount of material was tested for solubility with RT water: it dissolved quickly to a clear solution.
All being well I will determine the Al content of this sample, as a first step to composition analysis.
[Edited on 5-6-2014 by blogfast25]
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blogfast25
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The ASH I used has a reported Fe content of max 0.006 w%. In my case much of this iron must come from the HCl, which I know contains some.
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CHRIS25
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Very interesting and conclusive Gert.
As a side not, I have had my broken up chlorosulphate in a dessicator bag with calcium chloride as dessicant, outside in the unusually bright sun for
8 hours. I have just opened the bag and got an obnoxious pong of HCl fumes. The formally yellow crystalline solid is for the best part now utterly
white, though the larger bits still a bit yellow. They are solid But with one proviso, they can still be squeezed like icing sugar texture between
your fingers, no change in weight though, so no evaporation of water occurred, and the calcium chloride smelled of HCl. So there was some absorption
caused by the heat, but no change at all in the "wetness" of the product.
This I did not expect: After an hour in doors and in open air the chlorosulphate has gone completely and totally and utterly snow white, the whole
lot, every grain, and still smells strongly of the Chloride, so it has not decomposed to aluminium sulphate.
[Edited on 5-6-2014 by CHRIS25]
‘Calcination… is such a Separation of Bodies by Fire, as makes ‘em easily reducible into Powder; and for that reason ‘tis call’d by some
Chymical Pulverization.’ (John Friend, Chymical Lectures London, 1712)
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. (William Penn 1644-1718)
The very nature of Random, Chance development precludes the existence of Order - strange that our organic and inorganic world is so well defined by
precision and law. (me)
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blogfast25
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Chris:
It cannot be excluded at this point that the product is decomposing while one dries it. It would then emit HCl gas, almost certainly...
Once my product is sufficiently dry I will test for decomposition. If it decomposes that easily, we may never know its exact, initial composition.
It's possible (as a hypothesis) that as a solid it can only exist in very strongly acidic solutions.
Describe what you understand by 'wetness', please?
[Edited on 5-6-2014 by blogfast25]
[Edited on 5-6-2014 by blogfast25]
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