Question

The correct name for the complex ion $\left[CoCl\right(ONO\left)\right(en{)}_2{]}^{+}$ is

• A. chlorobis(ethylenediamine)nitrito-O-cobaltate (III) ion
• B. chlorodiethyldiaminenitrito-O-cobalt (III) ion
• C. chloronitrito-O-diethyldiamine cobaltate (III) ion
• D. chlorobis(ethylenediamine)nitrito-O-cobalt (III) ion

Answer 1

The correct option is D chlorobis(ethylenediamine)nitrito-O-cobalt (III) ion

The correct name for the complex ion $\left[CoCl\right(ONO\left)\right(en{)}_2{]}^{+}$ is chlorobis(ethylenediamine)nitrito-O-cobalt (III) ion.
One chlorine and two ethylene diamine ligands are named as chlorobis(ethylenediamine). The prefix bis represents two. Nitrito-O- represent the linkage through oxygen atom. The oxidation state of cobalt is written in roman numerals inside parenthesis.