HNO3 - 25-12-2004 at 18:20
I need to make some sodium sulfate. I have NaHSO4, H2SO4, and NaOH. What is the best way to do it, NaOH + NaHSO4 solutions?
The_Davster - 25-12-2004 at 20:27
Mixing a diluted solution of sulfuric acid with a sodium hydroxide solution and then evaporating would work. Pity to waste good sulfuric acid on
this, so the reaction you posted would be a better way to go.
Do you have copper sulfate? If so then add solid sodium hydroxide into a boiling solution of copper sulfate. CuO will precipitate which can be
filtered and the filtrate can be evaporated to get sodium sulfate. This is how I acquired my sodium sulfate actually( as a byproduct, I was in need
of CuO 
).
[Edited on 26-12-2004 by rogue chemist]
Joeychemist - 25-12-2004 at 20:50
Sodium sulfate was first created by decomposing sodium chloride with sulfuric acid.
HNO3 - 27-12-2004 at 14:05
I got 908g 99% CuSO4*5H2O at Walmart today. How does that reaction balance, rogue? I'm looking for 99% pure Na2SO4.
[Edited on 12-27-04 by HNO3]
FrankRizzo - 29-12-2004 at 20:10
CuSO4(aq) + 2 NaOH(aq) -> Cu(OH)<sub>2</sub>(s) + Na2SO4(aq)
HNO3 - 29-12-2004 at 20:53
That's just the thing. "Cu(OH)2" is blue, I've prepared it before. This reaction produces a black precipitate.
Mephisto - 30-12-2004 at 03:15
Your Cu(OH)2 decomposed by heat to black CuO.
Anyways, I wonder, that you can buy CuSO4 but not NaSO4 (Glauber salt) and simple purify it be recrystallization. As your NaSO4-solution made by the
method with CuSO4 will be contaminated with Cu-ions.
Repeat crystalization
chloric1 - 30-12-2004 at 03:59
Yes the material will ,in the begining, contain cupric ions but if you look at the CRC Chem and Phys. book or Langes you see some peculiar properties
of sodium sulfate. One is the fact it takes on 10 molecules of water below 33 Centigrade. When making artificial Verdigris from copper sulfate and
baking soda during the winter, when I let the liquid cool I got spectacular shards and splinters of Glaubers salts. This can be recrystalized from
hot DI or distilled water and chilled until white. Then you can melt the crystals and hold them at about 150 Centrigrade for an hour or two to get
anhydrous sodium sulfate. I hope this helps.
HNO3 - 30-12-2004 at 17:52
Sorry, everybody. After I shut my computer off last night I realized what actually happens.
CuSO4 + 2NaOH --> CuO + Na2SO4 + H2O
PS. Unfortunately, I don't have access to Merck, CRC handbook, etc. Besides, I like a printed copy, not electronic.
HNO3 - 11-1-2005 at 18:27
I finally succeeded in making some Na2SO4 by mixing warm solutions of CuSO4 and Na2CO3. I then vaccum filtered the solution and am in the process of
precipitating the Na2SO4 with Iso-propyl alcohol. I'll then filter the precipitate and declare victory.
chloric1 - 12-1-2005 at 03:51
This little excersise in metasynthesis reminded me of a proceedure I read in "Handbook of preparative Inorganic Chemistry" about producing
ammonium chlorate solution from ammonium sulfate and either sodium or potassium chlorate then adding alcohol to make a 50/50 aqueous alcohol mixture
to further precipitate the remaining alkali sulfate.
This sounds rather dangerous but if I dont let it crystalize I can mix it with strontium or barium oxide, hydroxide, or carbonate and heat to
volatalize the ammonia away! I really should examine this maybe in test tube quantites first!
[Edited on 1/12/2005 by chloric1]
[Edited on 1/12/2005 by chloric1]
kclo4 - 21-1-2005 at 22:18
Epsom salt (MgSO4) and Noah works and after the reaction is finished the Mg(OH)2 sinks to the bottom
[Edited on 23-1-2005 by kclo4]
Theoretic - 22-1-2005 at 15:06
NaHSO4 could be decomposed to Na2SO4, first giving off water then SO3.
Sodium Sulphate Solubility Data
MadHatter - 23-1-2005 at 05:38
From the CRC 62<sup>ND</sup> Edition 1981-1982(grams per 100 ml H<sub>2</sub>O)
Na<sub>2</sub>SO<sub>4</sub>(anhydrous):
4.76 @ 0C____42.7 @ 100C
Other Solvents: soluble glycerin; insoluble alcohol
Na<sub>2</sub>SO<sub>4</sub>.7H<sub>2</sub>O(heptahydrate):
19.5 @ 0C____44 @ 20C
Other Solvents: insoluble alcohol
Na<sub>2</sub>SO<sub>4</sub>.10H<sub>2</sub>O(decahydrate):
11 @ 0C____92.7 @ 30C
Other Solvents: insoluble alcohol
Hope this is of use.
mick - 24-1-2005 at 15:56
I need to make some sodium sulfate. I have NaHSO4, H2SO4, and NaOH. What is the best way to do it, NaOH + NaHSO4 solutions?
Buy some baking powder or washing soda and add the acid until there are no bubbles
mick.