Question

IUPAC name [Co(en)2Cl2]+

Answer 1

diichhloridodiethylenediaminecobaltIIIion

Answer 2

The IUPAC name of $\left[\mathrm{Co}(\mathrm{en})_{2} \mathrm{Cl}_{2}\right]^{+}$ ion Dichlorobis (ethylenediamine) cobalt (III) ion.

IUPAC is a naming convention which states rules that are used to name compounds. The IUPAC-“International Union of Pure and Applied Chemistry” states rules that allows every compound to have a unique name.  

A general rule to follow is to start from the right or end and work backwards (i.e. right to left) to give the compound a name. In the above given compound, the metal Co is cobalt. We are given the ligand en which is ethylenediamine.  

There are 2 en ligands, so we prefix it with bis. Another ligand is Cl which is chloro. There are 2 Cl ligands, so we use Di as the prefix in chloro to get dichloro. The oxidation number of cobalt is 3, so we use the Roman Number for that, following the metal name as cobalt (III).