Could Sodium Gallium Sulfate or Potassium Gallium Sulfate be made in a similar technique as making Sodium Aluminum Sulfate or Potassium Aluminum
Sulfate?
Step One: Dissolve Gallium in Sodium/Potassium Hydroxide to form the Gallate.
(2 Ga + 2 NaOH + 2 H2O → 2 NaGaO2 + 3 H2)
(2 Ga + 2 KOH + 2 H2O → 2 KGaO2 + 3 H2)
Step Two: Add Sulfuric Acid to Gallate to form Sodium/Potassium Gallium Sulfate. This is really a two step reaction, but is simplified here.
(NaGaO2 + 2 H2SO4 → NaGa(SO4)2 + 2 H2O)
(KGaO2 + 2 H2SO4 → KGa(SO4)2 + 2 H2O)
Is this viable?
I am only asking this because I do not want to go using my limited supply of Gallium on a project I am not sure will work.HeYBrO - 1-1-2014 at 22:12
You could always try your hypothesis on a mg scale and report back.TheChemiKid - 2-1-2014 at 04:04
I will do it on a small scale, but at 0.7g of Gallium and 0.4g of Sodium Hydroxide.
I cannot do it on a milligram scale because I do not have a precise enough scale. That is definitely a future buy.
EDIT: I will post my findings when I am done.
[Edited on 1-2-2014 by TheChemiKid]bismuthate - 2-1-2014 at 04:53
The problem is that Ga dissolves very, very slowly in NaOH (in my experience). I would recomend using Ga(OH)3 instead of Ga.vmelkon - 2-1-2014 at 07:07
How would you identify it? By the Crystal structure?TheChemiKid - 2-1-2014 at 12:31
Yes.blogfast25 - 2-1-2014 at 13:44
The sodium gallium alum may not be the best choice: the sodium aluminium alum is one of the hardest to crystallise because it is very
water soluble at all temperatures. The ammonium aluminium alum by contrast is poorly soluble in the cold but very soluble hot.
For this first dissolve gallium in excess strong (50 %?) H2SO4:
[Edited on 2-1-2014 by blogfast25]eidolonicaurum - 3-1-2014 at 02:19
I have done a fair bit of work on the simple chemistry of gallium; I got a bit frustrated by the lack of information on gallium, so I decided to work
it out myself. I have made both potassium gallium sulphate and gallium sulphate. Gallium sulphate was interesting to make, I discovered that gallium
sulphate is insoluble in sulphuric acid. I ended up heating/boiling the acid with gallium to make it dissolve. The 50% concentration is about the
ideal one to use. I then evapourated the solution down to obtain crystals of gallium sulphate. Interestingly, they were reniform: kidney shaped. This
might be due to the small scale I was working on; they may have formed tiny crystals which then clumped together. After a while, I decided to turn
them into potassium gallium sulphate, by recrystallisation from a solution of potassium sulphate. They were not too difficult to form, in contrast to
aluminium it seems. The picture is of my double salt. The other thing is that you may have difficulty getting the gallium to dissolve in sodium
hydroxide solution, it is not as reactive as aluminium, closer to that of zinc. But I would be interested to hear of your exploits in this reaction
when you do it!
They were not too difficult to form, in contrast to aluminium it seems.
[Edited on 3-1-2014 by eidolonicaurum]
Interesting bit about the KGa alum.
But the highlighted bit is not true. KAl alum is very easy to prepare (various routes exist) and can be thermally crystallised very well, with 90 % +
actual yields and nice, chunky crystals.
