Question

In which of the following, the chemical formula and the name are incorrectly matched?
(A) $K[Pt(N{H}_3)C{l}_5]$- potassium amminepentachloroplatinate (IV)
(B) ${[Ag{(CN)}_2]}^{-}$ - dicyanoargentate (I) ion
(C) $K_3[Cr{(C_2{O}_4)}_3]$ - potassium trioxalatochromate (III)
(D) $N{a}_2[Ni(EDTA)]$ - sodium ethylenediaminetetra acetonickelate(IV)

Answer 1

Hint: All of the compounds in the above options are coordination compounds. . In the IUPAC name of coordination compounds, the oxidation state is also mentioned along with the central metal atom in roman form.

Complete step by step solution:
There are some rules which are followed for the naming of coordination compounds.
Step by step method followed for the naming of the coordination compound is:
The positive ion is named first and then the anion is named. The complex part is written in one word. The numerical prefixes used to indicate the number of ligands is di for 2, tri for 3, tetra for 4, Penta for 5, Hexa for 6, and the name is written without the hyphen.
Ligands are positive, negative, or neutral, the ligands are named according to the alphabetic order.
In the complex, the ligand is named first then the name of the central metal atom is written.
If the complex is a cation, write the ligand name, then the central metal atom with its oxidation state in Romans, and then the name of the anion.
If the complex is an anion, first, write the name of cation and the name of ligand and to the central metal atom add –ate along with its oxidation state.
So, the IUPAC name of $K[Pt(N{H}_3)C{l}_5]$ will be potassium amminepentachloroplatinate (IV) and the oxidation number of platinum is +4.
IUPAC name of ${[Ag{(CN)}_2]}^{-}$ will be dicyanoargentate (I) ion and oxidation state of silver is +1.
IUPAC name of $K_3[Cr{(C_2{O}_4)}_3]$ will be potassium trioxalatochromate (III) and oxidation state of chromium is +3.
IUPAC name of $N{a}_2[Ni(EDTA)]$ -will be sodium ethylenediamine tetra acetonickelate(II) and the oxidation state of nickel is +2.

Therefore, the correct answer is an option (D) $N{a}_2[Ni(EDTA)]$ - sodium ethylenediamine tetra acetonickelate(IV).

Note: In the naming of amines only one ‘m’ is used, but for the ligand ammonia ($N{H}_3$), the name ‘ammine’ is used. We can also use bis and tris at the place if bi and tri, respectively.