PtCl4.6NH3 [hexammine platinum (IV) chloride]. It gives 4Cl−ions and 6NH3, not involved in its ion because NH3 are present out of the complex of PtCl4. Hence,
PtCl4−6NH3→[Pt(NH3)6]Cl4→
[Pt(NH3)6]4++4Cl−
Total‌5‌ions
In Ni(CO)4,CO is very strong binding ligand, it is difficult to remove all 4‌CO from nickel. On other hand, CoCl3.5H2O dissociates into Co3+, 3Cl−ions and 5H2O molecules. Hence, only PtCl4.6NH3 gives maximum number of ions in aqueous solution.