Question

What is the IUPAC name of ${K_4}\left[ {Fe{{\left( {CN} \right)}_6}} \right]$ ?
A) Tetra potassium ferrocyanide
B) Potassium ferricyanide
C) Potassium ferrocyanide
D) Potassium hexacyanoferrate

Answer 1

Hint:${K_4}\left[ {Fe{{\left( {CN} \right)}_6}} \right]$ is the complex and salt which forms lemon – yellow monoclinic crystals. Use the rules of naming the coordination complex. Identify all the elements of the complex and name and number of compounds.

Complete answer:
For naming the coordination compounds following rules are necessary –
In naming the whole complex, the name of the cation is given first and therefore the anion second (just as for sodium chloride), regardless of whether the cation or the anion is that of the complex species.
Within the complex ion, the name of the ligand or ligands precedes that of the central metal atom.
Names of ligand end with 'o' if the ligand is negative such as chlorido for $C{l^ - }$ , cyanido for $C{N^ - }$ and hydro for $H$ and unmodified if the ligand is neutral such as methenamine for $MeN{H_2}$. Some other ligand names are 'aqua' for water, 'ammine' for ammonia, 'carbonyl' for CO, 'nitrosyl' for NO.
A Greek prefix (mono, di, tri, tetra, penta, hexa, etc.) indicates the amount of every ligand (mono is typically omitted for one ligand of a given type). If the name of the ligand itself contains the terms mono, di, tri, eg triphenylphosphine, then the ligand name is enclosed in parentheses and its number is given with the alternate prefixes bis, tris, tetrakis instead.
A Roman numeral or a zero in parentheses is employed to point the oxidation state of the central metal atom.
If the complex ion is negative, the name of the metal ends in 'ate' for instance, ferrate, cuprate, nickelate, cobaltate etc.
If quite one ligand is present within the species, then the ligands are named in alphabetical order no matter the amount of every. For example, $N{H_3}$ (ammine) would be considered an 'a' ligand and are available before $C{l^ - }$ (chloro).
Using these above rules, we can name ${K_4}\left[ {Fe{{\left( {CN} \right)}_6}} \right]$ as Potassium hexacyanoferrate.
Hence, the correct option is (D) .

Note:A complicated ion by naming the ligands and so metal ions. The oxidation number of the metal ion is written next to the metal ion in Roman number at intervals the parenthesis.