[Bias Binte Kamal]

What's the hybridization and shape of CoCl5 3- ion? I thought it's sp3d3 but the book says it's tetrahedral. Could someone help?

[Bias Binte Kamal]

Anyone?

[Borek]

sp³d³ is very crowded (which means high energy) and rather rare, whenever possible molecules will prefer more loose arrangements of atoms (typically much lower energy, as distances between atoms are higher and the energy is lower).

That's without even trying to analyze orbitals involved, there is probably more to that.

[Bias Binte Kamal]

Have been looking for it everywhere just can't find anywhere. Anyways, thanks.

[kabudiba2]

Not sure what this question is trying to test, but if the book says tetrahedral (which is correct for Cs3CoCl5, but I don’t know how you are supposed to know that without looking it up), can you figure it the hybridization out from there?

[mjc123]

The crystal structure contains CoCl₄ tetrahedra and isolated Cl^- ions. There is no CoCl₅^3- ion.
https://legacy.materialsproject.org/materials/mp-1105622/