Sciencemadness Discussion Board

Neodymium ? sulphate

nezza - 30-4-2011 at 10:10

I have prepared Neodymium sulphate before from the metal and sulphuric acid with no problems.

This may be a stupid question but

Recently I have attempted to prepare it from Neodymium chloride and sulphuric acid by metathesis. As Neodymium sulphate is relatively insoluble, esp in hot water I expected it to precipitate out when warmed.

2NdCl3 + 3H2SO4 > Nd2(SO4)3 + 6HCl

What I get is a very pale lilac crystalline precipitate which is almost insoluble in hot or cold water. The same thing happens when using a neutral sulphate in the reaction. This is not neodymium sulphate. Does anyone have any idea what it is ? and why I am not getting Neodymium sulphate

woelen - 30-4-2011 at 10:21

It is soluble in cold water, but you need to take the time for this. It dissolves slowly, very slowly. I have made the same material from Nd2O3 and dilute H2SO4.

http://woelen.homescience.net/science/chem/exps/neodymium/pr...

Apparently, neodymium sulfate exists in different forms, e.g. with free hydrated Nd-ions and with a sulfato complex of Nd. But the precise characteristic of the material is not known to me. Both materials, however react as Nd-sulfate.

IrC - 30-4-2011 at 11:10

Woelen can you do a nice page like that on making the sulphate from the metal? I have a Kg of the pure metal and I always wondered what would be the most fun to do with it. Be nice if you did the nitrate from metal also as it makes a better dopant for glow powders and miscellaneous other experiments (using the nitrate instead of other salts that is).


blogfast25 - 30-4-2011 at 12:42

Yes, neodymium sulphate is a bit of a strange material, as this thread of mine also evidences.

nezza - 1-5-2011 at 03:08

Thanks for the info folks.

It obviously contains sulphate ions as the clear supernatant gives as positive test for sulphate with Barium nitrate. I have attached a picture of the two "sulphates" I have.

Neodymium sulphates.jpg - 60kB