MeshPL
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Tin acetates
So... yeah. Tin acetates. I have some questions. And internet is reluctant to give answers. Maybe some of you guys will help?
1. Is dissolution in ~100% acetic acid a possible way to obtain a solution of tin (II) acetate? Can O2 or H2O2 speed up the process?
2. Will H2O2 or O2 further oxidise tin (II) acetate to tin (IV) acetate?
3. Will hydrolysis due to atmospheric moisture and water contained in H2O2 and produced from O2 be a serious problem, so as long as concentration of
tin is not too high, starting AcOH is nearly 100% and solution is used shortly after it is produced?
4. Will baking something covered in this solution in O2 atmosphere produce something covered in SnO2?
5. Will presence of Pb2+ Al3+ Ga3+ or In3+ influence answers?
I think:
1.Slow, but yes. H2O2 must be fairly cocentrated so as to avoid hydrolysis, O2 will work.
2. Yes
3. No, or not a serious problem
4. Yes
5. No
But those answers may have been influenced by wishful thinking.
Thanks for answers, clues and whatever alse helpful. Criticism is welcome.
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fluorescence
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Yes I know sometimes its hard to find literature. I'd check the literature for you I was at the University this week. Our library has huge book
collections on all elements even on Astatine chemistry. So there should be something in there.
Now I ran a query in Reaxys for your compound and some answers came up, note that this from quite old literature and was copied like the people back
then described it. If there are two possible oxidation states it can always be that they found the wrong. I don't think that I have acess to most of
them if they are too old but since I don't have a link in reaxys I don't want to spend too much time looking for it. I'll just add the paper that is
mentioned in reaxys so you can look it up for yourself:
For Tin(II) Acetate:
- One way here is Tin + Acetic Acid without any further discription, the source would be
Gazzetta Chimica Italiana, 1905 , vol. 35 II, p. 224
- Then there is Tin(IV)Oxide Hydrate + Acetic Acid (they say (IV) here but the result is (II)) the source is:
Journal of the Chemical Society, 1964 , p. 5942 - 5947
- Then there is Tin(II)Oxide and Acetic Acid, I have an experimental text here but I just give you the source instead since it should be available
Patent: US2004/192951 A1, 2004 ; The title of that patent is "Low melting point tin salt of carboxylic acid and method for producing
the same"
- Tin(IV) Oxide in Acetic Anhydride
Journal of the Chemical Society, 1964 , p. 5942 - 5947
- Another tin +Acetic acid with the note " heating Sn in acetic acid under N2 about 80 - 90 h; filtration of soln.; concg. soln.;; drying of
residue over KOH; sublimation in vacuum at 150°C;; "
The source would be Journal of the Chemical Society, 1964 , p. 5942 - 5947
- Tin + Acetic Anhydride, Zeitschrift fuer Anorganische und Allgemeine Chemie, 1948 , vol. 256, p. 113 - 124
I hope this helps you a bit.
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MeshPL
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Thanks! At least point 1 seems correct... however those publications are all obssesed with anhydrous compound... I assume that both tin acetates
should exist in a water containing solutions, so as long as AcOH concentration is high. Pb(AcO)4 can exist in quite wet AcOH, so tin acetates also
should.
I have no need for solid, anhydrous Sn(AcO)2/4. I need it in solution. I may checkthe points it, but I'll need to borrow reagents from school, and
currently I'm having a winter break... and I may not have as concentrated AcOH or as pure Sn as I would like.
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blogfast25
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I would start from a aqueous solution of an Sn(+2) salt and precipitate Sn(OH)2 with ammonia. Filter and wash to remove ammonia and anions.
Then dissolve the Sn(OH)2 in 50 w% HOAc and cold-oxidise the Sn(OAc)2 with H2O2 to Sn(OAc)4.
Whether a solid Sn(OAc)4 hydrate can be isolated by gentle removal of the solvent and excess HOAc I don't know: Sn(IV) isn't really a salt
former. And SnO2 is extremely insoluble, so the tendency to form hydroxy compounds should not be underestimated.
[Edited on 17-2-2016 by blogfast25]
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MeshPL
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No, I do not need solid Sn(AcO)4. I need it in a solution, of whatever composition, be it mostly AcOH or water. I'm wondering, what is the best way of
preparing such a solution. The reason why I need acetate is because it is not oxidising at low pH (necessary to keep Sn soluble) and lead acetate is
water soluble. Lead chloride may be soluble in HCl, but if it is decomposed it will leave PbCl2 not PbO.
Basically I will be trying to convert tin-lead solder to lead doped tin oxide. Or even more doped tin oxide. It seems that only acetates may have
suitable solubilities and decomposition pattrns.
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gsd
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I suspect the direct reaction of tin metal with acetic acid will be very slow. In any case you will have to use large excess of acid which will have
to be removed / recovered after all metal is consumed.
In my experience it is better to use HCl which readily reacts with Tin metal. slight excess of acid (about 15 to 20%)and heating is required to drive
the reaction to completion. The solution is then filtered to remove fine black (carbon) impurities and is then treated with NaOH solution to
precipitate unstable white Sn(OH)2, which after some time turns into black Stannous Oxide (SnO). This precipitate should be washed repeatedly to
remove any NaCl. This is very highly reactive form of SnO and should be stored under water if not used immediately. It is pyrophoric if dried.
This SnO easily forms Stannous Acetate when reacted with Acetic Acid.
gsd
[Edited on 17-2-2016 by gsd]
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blogfast25
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Quote: Originally posted by MeshPL  | | No, I do not need solid Sn(AcO)4. I need it in a solution, of whatever composition, be it mostly AcOH or water. |
Such a solution will need a considerable acid reserve (HOAc) to prevent hydrolysis.
Sigma sells Sn(SO4)2 in 80 % H2SO4, if I understand their ad well:
http://www.sigmaaldrich.com/catalog/product/sial/96556?lang=...
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MeshPL
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What do you mean by "considerable reserve"? 30% AcOH? 70%AcOH? 99%AcOH? Whatever, I'll check, but when winter break ends.
I think that Sn(SO4)2 is sold in solution it was made, Brauer's preparative inorganic chemistry describes it as soluble in dilute H2SO4, opposed to
hydrolysis in H2O.
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blogfast25
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| Quote: Originally posted by MeshPL | What do you mean by "considerable reserve"? 30% AcOH? 70%AcOH? 99%AcOH? Whatever, I'll check, but when winter break ends.
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That depends mainly on the Sn(+4) concentration: the higher the lower the pH needed. With HOAc there's a limit to how low you can go because it's a
weak acid.
Have you considered something like (NH4)2SnCl6? Quite soluble and doesn't hydrolyse even in neutral conditions. Easy
to prepare too...
Hexachlorostannates are strong enough to coexist with lead without lead chloride forming.
But I'm still not fully clear on what you mean by:
| Quote: Originally posted by MeshPL |
Basically I will be trying to convert tin-lead solder to lead doped tin oxide. Or even more doped tin oxide. It seems that only acetates may have
suitable solubilities and decomposition pattrns. |
[Edited on 17-2-2016 by blogfast25]
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MeshPL
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I'll try making Pb doped SnO2. From tin-lead solder The solution for baking will need to be:
-not too strongly oxidising especially considering low pH required to keep Sn(IV) in solution (nitrates ruled out)
-leaving PbO upon decomposition. Chloride containing solutions will likely leave PbCl2
-thermally decomposable
What leaves acetate ion.
I may add some additional dopant like Al to see its influence on conductivity...
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AJKOER
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My experience with some transition metals (to date, Ag, Cu, Pb and Fe) is that the action of vinegar, dilute H2O2 and some sea salt, an excellent
electrolyte (as there is an underlying electrochemical/galvanic cell reaction here) after jump starting the reaction in a microwave, it can proceed
unexpectedly rapid. Periodically reheat and add more H2O2 /vinegar.
Here is an illustration of possible half reactions for the case of Pb assuming similarity to the Zin-air battery (see https://en.m.wikipedia.org/wiki/Zinc%E2%80%93air_battery ), which in reality may not be precisely correct:
Anode: Pb + 2 OH- --> Pb(OH)2 + 2 e-
Cathode: H2O2 + 2 e- --> 2 OH-
Net cell: Pb + H2O2 --> Pb(OH)2
And, in the presence of acetic acid (HAc) and NaCl:
2 HAc + Pb(OH)2 --> PbAc2 + 2 H2O
[Edit] Some pictures illustrating the products of my suggested galvanic chemistry approach at https://www.sciencemadness.org/whisper/viewthread.php?tid=64... and at https://www.sciencemadness.org/whisper/viewthread.php?tid=61... and at https://www.sciencemadness.org/whisper/viewthread.php?tid=62... and at https://www.sciencemadness.org/whisper/viewthread.php?tid=27...
[Edited on 17-2-2016 by AJKOER]
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MeshPL
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So well. I tried dissolving tin in a mixture of 80% AcOH and "30%" H2O2. Didn't quite work or it proceeded extremely slowly. Heating it up resulted in
eventual evaporation of liquids leaving tiny pudfle of white SnO2 in H2O and nearly untouched piece of Sn.
AcOH and HNO3 mix didn't work either, tin passivated.
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