Question

How many unpaired electrons in `["Co"("CN")_6]^(3-)`?

Answer 1

`"The number is ZERO..........."`

Explanation:

`Co^(3+)` has a `d^6` electronic configuration.......and these are classically LOW SPIN, especially with strong field ligands such as cyanide.........

`[Co(C-=N)_6]^(3-)` is thus diamagnetic with no unpaired electrons.