$[NiCl_2(PPh_3)_2]$ is named as:

Dichlorobis(triphenylphosphine)nickel(II)

The correct answer is Option (2) → Dichlorobis(triphenylphosphine)nickel(II).

The correct name for \([NiCl_2(PPh_3)_2]\) is Dichlorobis(triphenylphosphine)nickel(II)

Oxidation State:

Nickel in this complex has an oxidation state of +2, as the chloride ions contribute a total of -2 charge, and each triphenylphosphine (PPh₃) is neutral.

Coordination Complex Naming:

The name begins with the ligands. "Dichloro" indicates the presence of two chloride ions. "Bis(triphenylphosphine)" specifies that there are two triphenylphosphine ligands attached to the nickel. "Nickel(II)" indicates the metal and its oxidation state

Thus, the full name is Dichlorobis(triphenylphosphine)nickel(II).

Why Other Options Are Incorrect:

Dichlorobis(triphenylphosphine)nickel(III): Incorrect because it incorrectly assigns an oxidation state of +3 to nickel.

Nickeldichlorotriphenylphosphorus(II): This is not the proper nomenclature; the ligands should be named separately.

Triphenylphosphinenickelate(II) phosphate: This name is not standard for coordination complexes and is incorrect for this compound.

In conclusion, the correct name for the complex is Dichlorobis(triphenylphosphine)nickel(II).