The coordination number of central ion of the complex obtained in the sodium nitroprusside test of sulfide ion is

The complex obtained in the sodium nitroprusside test of sulfide ion is,

${\mathrm{Na}}_4\left[\mathrm{Fe}(\mathrm{CN}{)}_5\mathrm{NOS}\right];$ 

Here, the central ion is Fe.  The coordination number of it is given is 6

 $\mathrm{Fe}=6$