Formula of oxalato copper (II) complex?

[jacknife360]

What is the coordination number of copper in the oxalato copper (II)? I'm thinking 6 or 8 but can't quite be sure.

 

Thanks for any help.

 

Its made by mixing 90*c potassium oxalate monohydrate (K2C2O4.H2O) with 90*c copper (II) sulphate pentahydrate (CuSO4.5H2O)

 

Cheers

[woelen]

I'm quite sure that the coordination number equals 4. This will result in the following complex:

 

[math]Cu(C_2O_4)_2^{\space 2-}[/math]

 

Is this complex stable? I can imagine that internal oxidation/reduction renders it unstable. This is an interesting thing to give a try though .