Unraveling the Mystery of an Unusual Compound

[mooncrater]

Homework Statement

I found out this reaction series in my textbook which is as:
##2Cu(NO_3)_2+2Na_2S_2O_3 \longrightarrow Cu_2(NO_3)_2 +Na_2S_4O_6+2NaNO_3##
## Cu_2(NO_3)_2+Na_2S_2O_3 (excess) \longrightarrow Na_4[Cu_6(S_2O_3)_5] ##
Though it is not balanced(latter one) but my question is about the complex that is formed. What is it's geometry and what is the hybridisation of ##Cu## in this complex?

Homework Equations

The Attempt at a Solution

I don't know. I have never seen any thing like this before. It's an awkward looking compound but still I have curiosity how these type of monsters are made up.

 

[nate808]

Dear fellow scientist,

Thank you for sharing this interesting reaction series from your textbook. The complex formed in the second reaction is known as sodium hexathio-cuprate(II) or Na4[Cu6(S2O3)5]. Its geometry is octahedral, with six ligands (S2O3) surrounding the central copper atom. The hybridization of the copper atom in this complex is d2sp3.

As for how this complex is formed, it is a result of the excess of sodium thiosulfate (Na2S2O3) being added to the copper(II) nitrate (Cu(NO3)2) solution. The excess thiosulfate ions coordinate with the copper ions, forming the complex. This type of coordination is known as chelation, where a ligand binds to a metal ion at multiple points.

I hope this helps answer your question and satisfy your curiosity about the formation of this complex. Keep up the good work in your studies!