Question

Complex compound $\left[Cr\right(NCS\left)\right(N{H}_3{)}_5\left]\right[ZnC{l}_4]$ will be :

• A. colourless and diamagnetic.
• B. green coloured and shows coordination isomerism.
• C. green coloured and shows linkage as well as coordiantion isomerism.
• D. diamagnetic and shows linkage isomerism.

Answer 1

The correct option is C green coloured and shows linkage as well as coordiantion isomerism.

In the compound $\left[Cr\right(NCS\left)\right(N{H}_3{)}_5\left]\right[ZnC{l}_4]$, the cation contains chromium with +3 oxidation state.
3 electrons are present in $t_{2g}$ levels. Hence, the complex is green in colour.
NCS is ambidentate ligand and can be linked through either N atom or thorough S atom. This gives rise to linkage isomerism.
Since, both cationic and anionic parts are complex ions, hence, coordination isomerism is also possible.