Question

The IUPAC nomenclature for $\left[\mathrm{Ni}{\left(\mathrm{CO}\right)}_4\right]$ is________

Answer 1

IUPAC Nomenclature of Coordination Compounds

• The cation's name comes first, followed by the anion's name.
• The ligand or ligands' name comes before the name of the central metal atom.
• If the ligand is negative, the name usually ends in 'o', and if the ligand is neutral, it usually ends in 'unmodified.'
• The number of ligands is indicated by a Greek prefix, such as mono, di, tri, tetra, penta, hexa, and so on.
• The oxidation number of the central metal atom is indicated by a Roman numeral or a zero in parenthesis.
• The name of the metal ends in 'ate' if the complex ion is negative, such as ferrate, cuprate, nickelate, cobaltate, and so on.
• If the species contains more than one ligand, the ligands are called in alphabetical order, regardless of their number.

IUPAC nomenclature for $\left[\mathrm{Ni}{\left(\mathrm{CO}\right)}_4\right]$

• A ligand is carbonyl $\left(\mathrm{CO}\right)$, while nickel $\left(\mathrm{Ni}\right)$ is the center metal atom.
• Since $\mathrm{CO}$ is a neutral ligand, its oxidation number is zero.
• The oxidation state of nickel in $\left[\mathrm{Ni}{\left(\mathrm{CO}\right)}_4\right]$ is zero.
• No need to add –ate to the central metal atom because it is a neutral compound.
• IUPAC nomenclature for $\left[\mathrm{Ni}{\left(\mathrm{CO}\right)}_4\right]$ is Tetracarbonylnickel(0).