blueberry58
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MgCl2 + Na2S2O3 = MgS2O3 + 2NaCl
I am not chemist but MD but I need to prepare MgS2O3 in small quantity.
With this reaction
MgCl2+NaS2O3= MgS2O3+2NaCl
This was taken from Enclyclopedia of the Alkaline Earth Compounds by Richard Ropp.
When I mixed the reactants 1 M both, at normal temperature, nothing happens. Heating in a microwave forms some white flakes that I dont know what is.
After reaction is performed the author say that separation from NaCl ocurrs by crystallization at low temperature (-9,5 Celsius degrees) of the
product. salt out temperature
What I am doing wrong?
Thank you for your help.
Alejandro Fernandez
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blueberry58
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Sorry I forgot something
I dont know the proper temperature to use and the time of the reaction. But too is an issue the pH of the sol.
Thank you
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DraconicAcid
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Lange's Handbook says that magnesium thiosulphate is very soluble in water. You'd need to try higher concentrations, mix them, and cool the mixture
down in a freezer (not a microwave).
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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blueberry58
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Thank you DraconicAcid:
When you say high concentration its means saturated?
What temperature would you use?
Thank you.
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blueberry58
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Magnesium Thiosulfat Synthese
Wiith a little effort I could prepare magnesium thiosulfate. As I was unable to separating MgS2O3 from NaCl, I had to use the following process:
Na2SO2(aq)+MgCl2*6H2O(aq) = MgSO3*6H2O(s) +2NaCl(aq)
8MgSO3(s)+S8(s)=8MgS2O3(aq)
Altough I still doubt because I got a very hygroscopic salt. The test with potassium iodide exhibits a clear aspect, silver nitrate produces yellow
opacity and then black. Both indicate that it is a thiosulfate. By mixing with hydrochloric acid diluted a haze white-yellow appears and odor of
sulfur dioxide. Also indicates that thiosulphate is not magnesium sulfate.
Has anyone had experience with this salt?
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blueberry58
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I have prepared some MgTS using magnesium sulfite and elemental sulfur, 1:1 mole ratio. This product is unstable on heating. If I heat this clear
solution to achieve its crystallization, sulfur returns to form.
I decided use just low heat ( 60 degrees) and it become a kind of jam that does not crystallize. On heating more strongly it returns to liquid state.
What should I do in this case?
Thank you.
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