The IUPAC name for following complex compound

\(K[Au(Br)(ONO)(SO_4)(NH_3)]\) is

Potassium amminebromidonitrito-O-sulphatoaurate (III)

The correct answer is option 4. Potassium amminebromidonitrito-O-sulphatoaurate (III).

Let us break down the IUPAC name "Potassium amminebromidonitrito-O-sulphatoaurate (III)" to understand each component:

1. Potassium: This part of the name indicates the cation associated with the complex, which is potassium (K). Potassium is the counterion that balances the charge of the complex.

2. Ammine: The ligand "ammine" represents the ammonia molecule \((NH_3)\). Ammonia is a common ligand in coordination complexes.

3. Bromidonitrito: This part of the name indicates the presence of the ligand bromido \((Br)\) and nitrito \((NO_2^-)\). "Bromido" refers to the bromide ion \((Br^-)\), and "nitrito" refers to the nitrite ion \((NO_2^-)\).

4. O: The "\(O\)" indicates that the ligands bromido and nitrito are linked to the central metal atom through an oxygen atom. This notation is used to specify the coordination mode of the ligands.

5. Sulphato: The ligand "sulphato" represents the sulphate ion \((SO_4^{2-})\). Sulphate is another common ligand in coordination complexes.

6. Aurate (III): This part of the name indicates the central metal atom and its oxidation state. "Aurate" specifies that the central metal atom is gold \((Au)\), and "\((III)\)" indicates that its oxidation state is \(+3\).

Putting it all together, the IUPAC name "Potassium amminebromidonitrito-O-sulphatoaurate (III)" describes a coordination complex containing potassium cation, ammonia ligand, bromide ion, nitrite ion, sulphate ion, and gold (III) as the central metal atom.

This naming convention follows the rules of IUPAC nomenclature for coordination compounds, where ligands are listed alphabetically and prefixed with their coordination number and bonding mode. The name provides detailed information about the composition and structure of the complex.