Question

The IUPAC name of ${K_2}\left[ {Ni{{(CN)}_4}} \right]$ is:
(A) nickel tertracyanokalium(I)
(B) potassium tetracyanonickelate(II)
(C) tetracyano nickel kalium(I)
(D) potassium nickel tetracyanide

Answer 1

We know that all the inorganic and organic chemical compounds are named according to the rules provided by IUPAC which stands for International Union of Pure and Applied Chemistry. There are a set of rules for naming the coordination complexes which we will see in detail in the solution and then name the above given compound.

Complete answer:
So as we know, all the chemical compounds are named according to the rules given by IUPAC (which stands for International Union of Pure and Applied Chemistry). So here are the rules for naming a coordination complex:
- First the cationic part in the complex is named and then the anionic part of the complex is named.
- In the complex anions, first the ligands are named and according to their repentance in the complex, a prefix is added to their name such as di, tri tetra, and so on.
- The name of the ligands end with “o” such as chloride is written as chloride and cyanide is written as cyano.
- Now, the central metal atom is named and a suffix is added which is “-ate” to its name.
- Oxidation state of the metal atom is written in roman numbers next to the name of the metal atom. The oxidation state should be mentioned in parenthesis.
So, now following the above mentioned rules, the IUPAC name of the given compound ${K_2}\left[ {Ni{{(CN)}_4}} \right]$ is found to be (B) potassium tetracyanonickelate(II).
Hence, the correct option is (B) potassium tetracyanonickelate(II).

Note:
If we have to name the cationic part of the complex, then the name of the metal atom remains the same and no suffix like “-ate” is added to its name unlike that in the case of anionic part. Some ligands have different names like water is written as aqua while naming the coordination complexes.