Question

Draw the structure and write the hybridisation state of the central atom of the following specie: 

[NiCl₄]²⁻

Answer 1

1. The central atom is Nickel (Ni) in the +2 oxidation state, coordinated to four chloride (Cl⁻) ligands.
2. The complex has a tetrahedral geometry because of the four chloride ions surrounding the nickel ion.
   
3. The central Ni²⁺ ion undergoes sp³ hybridisation.
4. The hybridisation involves one s orbital and three p orbitals from nickel, which combine to form four hybrid orbitals. Each of these hybrid orbitals forms a bond with a chloride ion.
5. The resulting geometry of the complex is tetrahedral.
6. This complex is tetrahedral in shape. It is diamagnetic as all the electrons present in it are paired.