Question

The IUPAC name of the wilkinson's catalyst $\left[ {RhCl{{\left( {PP{h_3}} \right)}_3}} \right]$ is,
A. Chlorotris (triphenylphosphine) rhodium (I)
B. Chlorotris (triphenylphosphine) rhodium (IV)
C. Chlorotris (triphenylphosphine) rhodium (0)
D. Chlorotris (triphenylphosphine) rhodium (VI)

Answer 1

Hint: Wilkinson’s catalyst is the coordination compound in which the rhodium (Rh) is the coordination centre. This catalyst is used in the hydrogenation of the alkenes.

Complete answer:
Organic chemistry deals with millions of compounds in order to clearly identify, then a systematic method of naming them has been developed and called IUPAC (International union of pure and applied chemistry). The colour of the catalyst is reddish-brown and it is insoluble in water. It has square planar geometry.
Rules are applied for naming of coordination compound:
(i) Positive part of complex compounds will be named first, followed by the negative part.
(ii) Ligands are named first in alphabetical order, followed by central atom (reverse in case of writing formula).
(iii) Prefixes mono, di, tri, tetra etc. are used to indicate the number of ligands. Prefixes bis, tris, tetrakis are used for complex ligands (including a numerical prefix).
(iv) Oxidation state of central atom / ion is indicated in roman numerals in brackets after the name of metal.
(v) Name of anionic ligands end with ‘O’, Cationic ligands end with ‘ium’. For neutral ligands, regular names are used except ‘aqua’ for ${H_2}O$ ’ammine’ for $N{H_3}$, ‘nitrosyl’ for $NO$, ‘carbonyl’ for $CO$. These are placed within brackets.
Hence, the name of $\left[ {RhCl\left( {PP{h_3}} \right)} \right]$ is chloride tris (triphenylphosphine) rhodium (i)

Then, the correct option is (A).

Note: Remember that always start naming in alphabetical order. It is important for writing systematic names and formulae, particularly when dealing with isomers. It is very convenient to get information about the constitution of a compound if we know the formula, mononuclear entities contain a single atom.