Question

[Cu(NH3)4]SO4 in this is SO4 behaves as ligand

Answer 1

Oxidation no. of Cu in [Cu(NH3)4]SO4 is 2. As such it will have 3d9 electronic configuration. Anyone will think now that it should have sp3 hybridisation. But there is an exception here. NH3 being a very strong field ligand shifts the unpaired 3d orbital to the 4p orbital. Now the remaining 3d and 4p orbital will take part in hybridisation and the 4 NH3 ligands will now bond with them. The hybridisation as such will be dsp2 .