Sciencemadness Discussion Board

Synthesis of tantalum nitrate

ONeill - 14-11-2012 at 00:48

Hey folks!

I´m searching for a synthesis of tantalum nitrate (Ta(NO3)x). I think x=5 is the most common version, but any other oxidationsstate would be good, too. Any hints would be helpful, thank you in advance.

Cheers ONeill

woelen - 14-11-2012 at 01:04

In general it is not possible to make pure oxoanion salts of elements in high oxidation states. Borderline behavior is obtained for oxidation state +3, e.g. Cr(NO3)3 and Bi(NO3)3, but there already is a tendency to formation of basic salts and mixed oxides/other anion, e.g. (BiO)NO3 or Bi(OH)2(NO3).

For oxidation state +5 you really can forget about making pure salts, e.g. Ta(NO3)5 certainly cannot be prepared. Maybe it is possible to make (TaO)(NO3)3 or (TaO2)(NO3), but I even doubt the existence of these.

Chlorides to exist, e.g. TaCl5 and TaOCl3, but these are purely covalent compounds and these immediately hydrolyse in water, giving Ta2O5 and HCl.

ONeill - 16-11-2012 at 01:57

Hello woelen,

thank you very much for you detailled answer.

Cheers Chris