Question

IUPAC name of $ {H_2}\left[ {PtC{l_6}} \right] $ is:
A. hydrogen hexachloroplatinate $ \left( {IV} \right) $
B. dihydrogen hexachloroplatinate $ \left( {IV} \right) $
C. hydrogen hexachloroplatinic $ \left( {IV} \right) $ acid
D. hexachloroplatinic $ \left( {IV} \right) $ acid

Answer 1

Hint: The IUPAC nomenclature requires three specific characters, which are the ways of writing the central atom to be used, the number of ligands involved and the oxidation number of the given complex. The IUPAC nomenclature differs from that of the organic compounds as the geometry of the complex does not define the nomenclature.

Complete step by step solution:
For determining the IUPAC nomenclature of a specific complex salt, at first the oxidation number of the central atom needs to be determined. In the given complex $ {H_2}\left[ {PtC{l_6}} \right] $ the oxidation number of $ Pt $ needs to be determined. Let the oxidation number be $ x $ and from the associated hydrogen and chloride residues the equation for oxidation number will be:
 $ + 2 + x - 6 = 0 $
 $ \Rightarrow x = + 6 - 2 = + 4 $
After this, the ligand-bound with the central atom is written with the nomenclature of the metal ion in the given IUPAC name. The ions which are associated with the ligand and metal complex are given separately from the complex structure. As there are six chloride residues that are responsible for the formation of the complex, the naming used will be hexachloro. There is an associated suffix $ ( - ate) $ added to the name of the given central metal ion. There are two hydrogen which is associated with the given complex which is why the nomenclature used for hydrogen will be dihydrogen. Lastly, the oxidation number of the central metal ion is associated with the IUPAC name itself as roman numbers. Therefore, the actual IUPAC name of the $ {H_2}\left[ {PtC{l_6}} \right] $ complex can be written as B. dihydrogen hexachloroplatinate $ \left( {IV} \right) $ . This is based on the way in which IUPAC name is written for the given complex molecule.

Hence, option B is correct.

Note
The importance of the IUPAC name of the given complex salt depends on all the residues that are involved in the formation of a molecule. The complex salt that is present may have associated residues and ligands which are formed due to the electron filling up the vacant orbitals.