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AJKOER
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Actually, to be honest, from my quick read I miss the intent of the thread.
I agree that "Copper ammonium sulfate" is not a double salt. Actually, there is no double salt, so not likely much confusion in practice. Now,
seemingly more accurate would be [Cu(NH3)4(H2O)2](OH)2 or tetramminediaquacopper(II) hydroxide.
But even this is not accurate, in reality, as there can be many combinations of the ammonia and aqua liqands as long as there sum is 6. Note, the
expression in the first brackets, the copper ammonium aqua complex, is the cation that actualy forms in solution.
So, excuse me if I prefer the dated naming convention, in this instance, as it does not present false accuracy.
[Edited on 26-3-2014 by AJKOER]
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DraconicAcid
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Quote: Originally posted by AJKOER  | Actually, to be honest, from my quick read I miss the intent of the thread.
I agree that "Copper ammonium sulfate" is not a double salt, actually there is no double salt so not likely much confusion in practice. Now, seemingly
more accurate would be [Cu(NH3)4(H2O)](OH)2 or tetramminediaquacopper(II) hydroxide. But even this is not
accurate, in reality, as there can be many combinations of the ammonia and aqua liquands as long as there sum is 6.
So, excuse me if I prefer the dated naming convention, in this instance, as it does not present false accuracy. |
Copper(II) often does not have a coordination number of 6. Tetramminecopper(II) complexes without other ligands are common.
Copper ammonium sulphate IS a double salt. There is a difference between ammonia (which can act as a ligand) and ammonium (which is a cation). It is
not a question of different naming conventions, they are two completely different things.
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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The Volatile Chemist
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| Quote: Originally posted by DraconicAcid | | Quote: Originally posted by AJKOER | Actually, to be honest, from my quick read I miss the intent of the thread.
I agree that "Copper ammonium sulfate" is not a double salt, actually there is no double salt so not likely much confusion in practice. Now, seemingly
more accurate would be [Cu(NH3)4(H2O)](OH)2 or tetramminediaquacopper(II) hydroxide. But even this is not
accurate, in reality, as there can be many combinations of the ammonia and aqua liquands as long as there sum is 6.
So, excuse me if I prefer the dated naming convention, in this instance, as it does not present false accuracy. |
Copper(II) often does not have a coordination number of 6. Tetramminecopper(II) complexes without other ligands are common.
Copper ammonium sulphate IS a double salt. There is a difference between ammonia (which can act as a ligand) and ammonium (which is a cation). It is
not a question of different naming conventions, they are two completely different things. |
As far as I know, it's more common for ammonium complexes to be insoluble in water (Am I right?). What I produced is most likely not a complex (It
probably decayed into multiple things), though it could easily be tested by someone else. The existence of such a compound does indeed seem
questionable though. I could test the "Cupric Ammonium Acetate" solution I produced for complex-ing or ambient ammonia. Are there ways to do either?
(DraconicAcid, I wouldn't mind if you checked my last post (First page) directed towards you).
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AJKOER
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Draconic Acid:
I am working on my Nook, and it takes time to correct.
Please see my edited text.
Here is a reference on the point that there is actually nothing sacred about the tetraamminediaquacopper cation as depending on the ammonia
concentration in solution, one could have anywhere from [Cu(NH3)(H2O)5]2+ to [Cu(NH3)5(H2O)]2+, with the latter occurring in very concentrated ammonia
solutions. See first page at: https://docs.google.com/viewer?a=v&q=cache:IjHK0vuBZhcJ:...
---------------------------------------------------------
Now, why not a double salt, per Wikipedia on Double salts, to quote:
"Double salts are salts containing more than one cation or anion, obtained by combination of two different salts which were crystallized in the same
regular ionic lattice. Examples of double salts include alums (with the general formula MIMIII[SO4]2•6H2O) or Tutton salts (with the general formula
[MI]2MII[SO4]2•6H2O).[1] Other examples are potassium sodium tartrate and bromlite.
Note that double salts should not be confused with a complex. When dissolved in water, a double salt completely dissociates into simple ions while
complexes do not; the complex ion remains unchanged. For example, KCeF4 is a double salt and gives K+, Ce3+ and F− ions when dissolved in water,
whereas K4[YbI6] is a complex salt and contains the discrete [YbI6]4− ion which remains intact in aqueous solutions.[1] It is therefore
important to indicate the complex ion by adding a square bracket "[ ]" around it."
So, based on this definition and where my cited reference places the brackets, we have a complex and not a double salt.
[Edited on 27-3-2014 by AJKOER]
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