Answer is 3
Hybridisation will decide on the basis of pph3. Square planar.
See in spectrochemical series Cl is far-far way from pph3.
Ni(+2) has d(8) electronic configuration it will pair the unpair electrons.
Is it always true if there is a strong ligand and a weak ligand than we do according to strong ligand?
Yeah if difference between ligand is more in spectrochemical series.
See in Inorganic chemistry there is a lots of exceptional
Learn these points.
CO and weak ligand will always form tetrahedral with coordination no 4
CN will always form square planar with coordination no 4
If you wants more short trick to remember hybridisation please let me know.
Do share if you have some short tricks.
See for coordination no 6
Transition metal of period 4 onward will have d2sp3 hybridisation irrespective of ligand.
If central metal is fe, Ni,Zn and ligand is NH3 then treat this Ligand as a weak ligand.
#if metal is Pd, Pt and coordination number is 4 always form dsp2 irrespective of ligand.